Modify TC-16A
I bought a TC-16A, even though I knew that it doesn’t work on my D100 or the D200 I was planning to get. But I thought I’ll take it anyway, since I don’t have any usable converter and this one is pretty cheap compared to the other ones. I figured I’ll try to find out why it doesn’t work, since I couldn’t even find any useful information on that.
Research
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First thing I noticed is the different pin layout on the TC-16A compared to all my other AF-lenses. I’ll call these pins 1 X 3 4 5 X 7 (as seen on the picture of the TC, where the X’s stand for empty spaces). |
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(above=TC-16A, here=Sigma 8mm) pins here: 1 X X 4 5 6 7 |
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So I openened the Converter to have a look where these pins connect to. There is a CPU inside, just like in any AF-lens. |
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This is the front of the circuit print. It features a NEC D7554G502 “CPU” as its main component. Just for your information: the circuit print continues on the left all the way to the connectors: the top circuit path (top left pin of the IC) connects to pin 1 the next lower one (on left of the top resistor) to pin 3, then the next one down pin 4, then pin 5, and the very bottom circuit path (bottom right pin of the IC) connects to pin 7. |
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This is an IC I found which seems to be compatible. Turn it anticlockwise by 90 degrees to have it in the same orientation as on the picture above (front view). |
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On the back all the connections are visible.
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| I didn’t want to open any of my AF lenses, to see where the difference was, but I didn’t need to after I found the results of someone having done exactly that (I could no longer find the source where I found this, so I cannot mention it here): [edit] Tazman (comment 75) found the source: A very interesting thread by “Ro Ro” on photo.net [/edit] |
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And what do you know!? – its basically identical! Except for one difference, which is exactly what I was hoping for…
Pin 3 (on the TC) which was out of place anyway is connected to the IC in the same way that Pin 6 (on the AF lens) is connected!
Research result: JUST MOVE PIN 3 to the (unused) position 6… that’s it!!!
Method
A quick note to begin with: Most the feedback I get about this page is that the people tried this modification and lost one of the small golden springs. So please be careful with those – I don’t know where to get any spares!!
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This by the way is what the circuit print looks like at the other end. |
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So I drilled a hole (1.4mm for those who want to know, or just slightly wider – the metal contact that needs to fit through is exactly 1.4mm wide) in position 6, and made sure the metal contact fits well, and moves easily. I drilled it by hand, NOT with a Dremel or so, but just by rolling the drillbit between my thumb and index finger. It took a little longer, but gave me a much cleaner result. |
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Luckily Nikon didn’t save every milligram of plastic they could and there is already a notch in which the metal contact can slide, without touching the other contacts. |
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Now I soldered a little wire onto the little spring to electrically connect it to its old position on the circuit print. |
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Then put everything back together… |
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Oops, one more problem… The contact on the circuit print for Pin 5 is a little too wide and our new pin 6 would touch it as well, which is not good… |
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So I just covered that side of the contact with a little bit of cello-tape (I know this is not perfect, but the best Idea I could think of to make the whole process more or less reversible). |
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NOW put everything back together.. |
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And finished!!! :-) |
D100 specifics
(probably more cameras, eg D70, D50, D80, F100, F80, etc)
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Just one more thing… |
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(I got an F E.E Error on my D100) |
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A little something (don’t know what it’s called) that moves a switch and this tells the D100 (and other cameras) that the aperture ring has been turned to minimum aperture (and so enables controlling all apertures via the camera). If you cut a piece of hard plastic (I used an old PC CPU fan) into the shape above, it fits really well (in a very good position) in between the Converter and the little cover for the “CPU compartment”. |
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Now we’re really done!! – That’s it! |
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This is how it looks on my 500mm f/8 Reflex Lens One more note: the Aperture the TC transmits to the Camera is always f1.0, as minimum and maximum aperture. So it is not possible to change the aperture at all. My 500mm (which I mainly bought this converter for) has a fixed aperture, so it’s not quite so bad, but it would be nice if this were different. |
D200 specifics
(probably applies to D1 and D2 series, D300 and D3 as well as F4, F5 F6)
Since the D200 has AI coupling, there is no physical switch like for the D100. Therefore, the little plastic thingy will not be necessary. However, somehow it didn’t work anyway (same F E.E error). The Trick is: go to CSM (Custom Setting Menu) under f: “Controls”, position f5: “Command Dials”. There, under “Aperture Settings” choose “Aperture Ring”. This means you can’t control the Aperture via the subcommand dial anymore (so you’ll want to switch it back when you put a normal AF-D lens on the camera again).
Tools used
- Philips No.000 Screwdriver
- 1.4mm drillbit
- a very fine-tipped soldering iron
- a dremel (only for shaping the little plastic piece)
Parts used
- 1cm of very thin, insulated wire
- a small piece of hard (nonbrittle) plastic – got mine from an old PC CPU-fan
Limitations
OK, basically it works, but the use is very limited. It’s limited to the maximum aperture of the lens attached. On the D100 that’s it. Nothing you can do about it. On the D200 it only meters for maximum aperture, even if you set it to a different aperture. If you do want to use a different aperture, you’ll just have to dial in some exposure compensation.
Future Ideas
To overcome the aforementioned limitations, I believe the only solution would be to replace the chip with one that has a range of apertures, and not just “f1″ for both minimum and maximum aptertures (this is what imposes the limitations).
Notes:
I will not be held responsible for any problems caused directly or indirectly by following the above instructions/information. Use at your own risk!
April 26th, 2009 at 02:12
I just wanted to thank you for posting this information, and to let you know that I successfully performed this conversion and now have a TC-16A working on my Nikon D700.
But those little springs were sure painstaking to deal with!
April 28th, 2009 at 14:54
Thanks for this detailed description.
However, since I do not have excellent DIY skills, I wonder
whether it would do to take the contacts and chip from some other lens and put it in?
April 28th, 2009 at 15:15
@Kim: yes, that would probably be an even better idea. however, it might be difficult to find a complete circuit with chip and contacts that will fit. So you will have do some “DIY” either way. But a complete chip would get rid of the limitations with the aperture selection to a certain extent.
April 29th, 2009 at 04:25
Thanks for sharing!
Do you think it will work better if I follow the circuitry of the AF 35-70, and modify TC exactly like it.
1st: move Pin3 to Pin6
2nd: Connect IC-Pin3 and IC-Pin4
3rd: Move Pin5 from IC-Pin3 to IC-Pin2
Then we will have the same circuit as the AF 35-70.
May 7th, 2009 at 12:14
I presume that that won’t make any difference, unless you are also putting the cpu from the 35-70 onto the TC-16a circuit.
the cpu is specific to each lens, and is there to give the camera lens-specific info. It’s not just about which pins are connected, but rather how the specific CPU uses these pins.
May 21st, 2009 at 13:14
If I am actually putting from 35-70 cpu on the TC16a electric circuit. How to revise P10x or the P11x signals, may let len cpu report that minimum aperture to camera cpu, lets camera cpu be possible to transfer and to control aperture.
thanks for your technical assistance.
May 21st, 2009 at 15:14
I’m not 100% sure what you’re asking, but to check the difference between the 35-70 circuit and the TC-16a circuit, I’ve layered the two images of the front and back of the circuit on top of each other, so you can see it better:
as you can see, the only difference is that PO1/SI and PO2/SO are not just directly connected but have an active component (probably a switching diode), and the other difference is that pins P11-2 and P11-3 are connected to ground.
P10x were labelled as “zoom contacts gray coded” which means that depending on zoom value, different combinations of these pins are connected to ground. Possibly it is the same for P11x, and that P11-2+3 being ground, that could be some coding as well. I’ll try if it changes anything with the TC chip.
I assume if you just disconnect P11x from ground when you put in the 35-70 chip, you should be able to control the aperture from the camera, but that’s just my (logical) assumption, I haven’t tried it. (If someone wants to send me a broken 35-70 lens, I will try it for you.)
May 21st, 2009 at 15:56
Cool, I just found out something new.
I tried disconnecting the two pins P11-2+3 from ground, and guess what:
this influences the min/max aperture setting, which was the biggest limitation of this modification.
if you remove pin P11-2 from ground, max-aperture is f/1.8, and focal length is transmitted as 50mm
if you remove both P11-2 and P11-3, max-aperture is f/4.0, focal length is 145mm but you get an FEE error unless you move the aperture ring 1 stop above min-aperture
if you remove just pin P11-3, max aperture is f/3.8, focal length is 48mm and the same thing applies with the aperture ring
(remember, if you want to use the sub-command dial to select aperture, you usually have to set the aperture ring to min-aperture and some lenses have a lock to keep it in that position – with the latter two options, this “lock” position is not min-aperture, but 1 stop above min-aperture.)
May 21st, 2009 at 16:38
Investigated some more, and found out why the above happens:
It seems nikon used the same chip for (at least) 4 lenses:
the TC-16a (obviously) (P112+P113 to ground)
the 35-70/3.3-4.5 (only P112 to ground)
the 70-210/4 (neither P112 nor P113 connected)
the 50mm /1.8 (only P113 to ground)
since these lenses have different aperture ranges (from max to min) the above symptoms occur with the aperture ring setting and FEE error:
the 50/1.8 has a range of (almost) 7 stops
the other two only have 6 stops.
so that has to be reflected by the minimum aperture setting the D200 and up read via the aperture ring.
(on “lower class” cameras, there shouldn’t be these problems, since this is taken care of by extra switch, which that little plastic thing in the conversion above hits, no matter if you set the lens to min-aperture or not.)
so that’s why the above happens.
you can then use the pins P10x to code the focal length, so if you mainly use the TC-16a for adding AF to a single MF lens, try to find a matching focal length in the above ranges, since the camera uses this value for it’s calculations (AF and expusure I believe) and of course it will be written into the exif fields.
My above suggestion of changing the chips with a 35-70 is therefore useless, as a simple pin-desoldering does the exact same thing.
May 22nd, 2009 at 04:44
wonderful !!!
i will try to let tc-16a + af 70-210 work fine according to the important information provided from you.
if you have any recommendation , please let me know !!!
thanks a lot.
July 13th, 2009 at 01:51
To disassemble and to perform the modifications are relatively easy stuff. The problem is to reassemble the thing and put everything in there, because the small wire you put make it dificult and after one paintaking hour I lose one small spring and leave it for all. Hard stuff my friend, hard stuff!
July 21st, 2009 at 18:46
Hey, guys – as I am in optics and not in electronics, this all seems very complicated to me. Simple question: Will a TC-16A work on NIKON DSLR with a 400mm f/2.8 AIS (manual), if not, which changes are required, who can make a modification, and how much will this cost? Are there differences between similar Nikon mount DSLRs? I have a Kodak DCS 14/n and think of getting a D300. Thanks
July 22nd, 2009 at 21:48
I have made the modifications on a TC-16A and used it on my D300 and my good old Nikkor 500mm/4 P. It worked like expected. Then I modified the CPU Printed Circuit Board by cutting the two tracks underneath the PCB to P112 and P113. (The lens has 6 F-stops and a max aperture of F just like 70-210/4). Now the light metering system works perfect by transmitting the aperture through the AI-ring to the camera. The aperture shown on the camera display and the EXIF data is correct. Only the EXIF data on the lens and focal length are false. The transmission of the aperture is not working on cameras like the D80 as there is no AI-ring. I must emphasize that the job is very delicate. The CPU PCB can be loosened by cutting some glue between the PCB and the plastic. But be careful.
July 22nd, 2009 at 22:03
Well, actually it should work on the D80 as well, if you somehow make sure the little switch at about 7 o’clock if you look into the lens mount of the camera is activated.
you can do that by either making a little plastic (or metal) thing onto the TC (as described above) or by sticking something into the switch itself, thereby jamming it.
Of course you have to remember to set the aperture on the lens to minimum aperture. then you can use the subcommand dial to change the aperture. This should also work on D300/D3 type cameras, which have an AI ring – if you leave the lens at min. Aperture, (and have the “Command Dials” Menu option set appropriately), you can use the sub-command dial to set the aperture.
Instead of cutting the PCB, I recommend bending up the legs of the CPU. – hold your soldering iron to the pin, and use tweezers to bend the pin while the solder is molten. Remove excess solder. That way the process is reversible.
July 23rd, 2009 at 09:41
Hi Oliver
I’m afraid that I don’t understand your point.
On the D80 the ‘pseudo AF’ is working perfect just as on the D300 (when the little switch is activated).
On the D80 the only difference after cutting the 2 wires is that the aperture is constantly displayed at F/4 instead of F/1. The exposure meter is not reflecting any change in the aperture setting. With the TC 16A mounted. I can’t use the dial on the camera to change the aperture setting as this requires electric connection between the lens and the camera. And there is no contacts on the lens side of the TC 16A. I can’t see how this can be improved on the D80 as there is no mechanic connection between the lens and camera either.
But on the D300 the exposure meter is working perfect and it possible to use the A-mode automatic exposure!
I really look forward to use my ‘new’ AF version of my old 500 mm. Thank you for the very detailed descriptions!
July 23rd, 2009 at 11:13
@Soren:
All Nikon lenses (except the newest Tilt/Shift lenses) have a mechanical connection for the aperture. The TC-16A just passes this through. The camera always keeps this spring-loaded aperture lever at its maximum position, so that the lens is wide open while you meter, focus and compose the shot. when you take the shot, the camera moves this lever to the position corresponding to the desired aperture setting. (it also does that when you press the DOF Preview button)
setting the aperture ring limits the minimum aperture of the lens. Moving the lever will only change the aperture between the set aperture (as the minimum setting) and maximum aperture (for metering, etc). So if you want the camera to have full control over the aperture, you have to set the aperture ring to minimum aperture of the lens, which will make the full aperture range controllable by the aperture lever.
The D300 (and other cameras with AI coupling) can read the position of the Aperture ring, and “know” what the aperture is currently limited to, and take that into account, whereas the D80 and the like can’t, so they have to expect the lens to be set to minimum aperture, or display an error. This is what that little switch which you jammed is actually for: to check whether the aperture ring is set to minimum aperture.
The electronic contact is made just by the TC, which pretends to be a lens. That’s why the Aperture range has to be the same as the lens that’s actually attached, because otherwise if you set the aperture to minimum aperture, that won’t correspond to the minimum aperture setting the camera is expecting for that lens.
Basically, if it works on the D300, it should work on the D80 if
A) you jam the little switch (sounds like you did that, since the camera displays f/4)
B) you leave the aperture ring at minimum aperture (so f/32 or so)
C) you use the sub-command dial instead of the aperture ring to select your new aperture.
July 23rd, 2009 at 21:08
It looks like you can get f/4 but is there a way to get f/5.6? Is there a way to make the camera just use the AI coupling and have it “know” that it’s f/5.6? On the D700 (and I guess the D300) you can tell the camera the lens focal length and max aperture and the camera LCD readout will show the appropriate aperture. Will this be the same regardless if I do the P112 and P113 modification?
July 25th, 2009 at 16:07
@Nathan:
the AI coupling mechanism has a fixed position for “Maximum Aperture” and a fixed distance for 1 stop.
it does not know anything else.
The CPU in the Lens (or in our case the TC which pretends to be a lens) tells the camera its ID, its current zoom setting and current focal setting if applicable. From this Info the camera knows the lens’
(current )max aperture eg f/4
aperture range eg 6 stops
as long as the Camera can get this information, it will use it. If there is no CPU, then the D700 (and all other Nikon DSLRs with AI coupling) can let you enter this information manually. This info is only for Display and entering into the EXIF data, it is not needed for Metering.
If you really need f/5.6 as the max Aperture, you will have to replace the the CPU with one from a lens that has 5.6 as a maximum aperture.
Or you can remove the CPU alltogether, and enter the data manually, but of course, you will also lose AF functionality.
July 25th, 2009 at 17:02
Hi Oliver
Thank you again for the detailed explanation!
My modified TC 16A is working correct with ‘semi AF’ and exposure metering on the 5oomm 4 P, both with my D300 and my D80.
And I understand a lot more on how my cameras are working!
July 29th, 2009 at 13:40
It is good to know that the TC-16A works flawless with the D2H without any modification. I use it regularly with a 180/2.8. The semi AF works well, and metering is perfect with AI coupling. The camera seizes the position of the aperture ring, displays that how many stops over full open, M and A modes work. With my oder body, D70, it does not work.
August 10th, 2009 at 19:32
Thank you, Oliver. I’m still on the fence whether to make the modification or not. Would you happen to know if you can use both pin 3 and pin 6 in conjunction? In other words can I have the best of both worlds and have both pins 3 and 6 active so it’ll work on both an older and newer camera?
August 12th, 2009 at 16:18
@Nathan: I wouldn’t do that. Nikon warns about the incompatability of the (unmodified) TC-16A with the newer cameras, so that alone is reason enough not to leave pin 3 connected, if you plan on using it on the newer cameras.
The modification is the best of both worlds: after the mod, the TC also works on older cameras, just like it does on the newer ones. Of course there’ll be a change (see the discussion about aperture issues, and it being recognized as a lens, not a TC) but it will work.
My method is entirely reversible, so if you’ll miss the way it worked on your old cameras, and don’t like the “new” way, then you can just put it all back to how it was – The only difference will be the newly drilled hole, which won’t be a problem.
August 20th, 2009 at 14:07
Hi there. I would like to thank for this post. I have just performed the modification and it worked. I used an old DvD player wire, witch is realy thin. There is one problem though: the AF does not uses all it’s range: I have to manualy aproach the focus to the object and only than, in a very strict fiel, the AF does something. I don’t know if this normal or not.
Thanks again.
MArco Pedrosa, Portugal.
August 20th, 2009 at 15:27
@Marco
Yes, this is completely normal. That is how the TC-16A has always worked, even on the older Cameras it was designed for. It’s amazing enough that it can autofocus at all, with any lens mounted on it.
August 21st, 2009 at 18:11
Hello Again. Yes, I agrre with you. I have just mounted an old tokina 400mm, completly manual and it went AF :)))) It is really amazing.
August 22nd, 2009 at 00:32
OK!!! AND WHAT ABOUT THE 16 AF, ANY POSSIBILITY TO CONVERT IT ALSO?
August 25th, 2009 at 14:13
Maybe the real message of my post was hidden, I repeat myself.
IF YOU HAVE A D2H YOU DO NOT NEED TO MODIFY THE TC-16A.
August 26th, 2009 at 18:54
@Armond: writing in ALL CAPS is considered screaming… please don’t do that.TC-16” (without the “a”)?
I guess you mean the “
This was made only for the F3AF and uses completely different AF-contacts, so there is no point in trying to convert it. You’ll be better off selling it – it should fetch a much better price than the TC-16A.
August 26th, 2009 at 19:18
@Antal: The D2 Series are compatible with the unmodified TC-16a. But not even the D3 is anymore, neither are the D200, D300 or D700, and especially not any of the “lower class” Nikon DSLRs. As far as I know, the D1 series were not compatible with it either.
September 1st, 2009 at 05:52
Hi Oliver,
Thanks for sharing the detailed steps to this modification. I had the teleconverter
modified accordingly and it does autofocus on my AIS 300/2.8, however I found that
the focus is consistently inaccurate on my D200 (always focuses to the front of the
desired focus point) even though the AF confirmation dot says focus is accurate and
there is a “beep” sound. Just wondering if this is an isolated case with my D200, or
whether anyone also has this problem….Thanks!
P.S. If I had the D300 I can probably adjust the focus point but I’m not prepared to
change my camera anytime soon..haha
October 12th, 2009 at 09:05
Very interesting discussion! Thanks Oliver and thanks to All….. but…my poor English makes me go astray.
At the end of games: to use “the best possible” the TC-16A with the 500 f.4 P on D300/D700 what should I do?
It ‘just the change indicated by Oliver or do I also “work” on the PCB?
Sorry for the bad English and many thanks to All again.
October 12th, 2009 at 10:35
Hi, first make the change described at the top.
If you want to also control your aperture properly (very advisable) also modify the PCB.
For your lens, I recommend “the 70-210/4 (neither P112 nor P113 connected)” This is the longest focal length, and also has a max. Aperture of f/4, just like your lens.
To disconnect pins P112 and P113, melt the solder with your soldering iron, then lift the pin up. This way you can reconnect it at a later time if you want to.
October 23rd, 2009 at 19:07
@Alex – I have precisely the same problem.
I just performed the procedure on my TC-16A to be used with my D200 and 500mm f/4 P lens. The autofocus behaviour seems correct (I used an unmodified one with my F4s once upon a time). However, the focus is consistently off by a small amount. I used to own the older style AF Sigma 500/4.5 APO and it suffered from the same problem. The focus adjustment feature of a D300 I borrowed was insufficient to correct the problem, and I suspect (though have not tried) that this would be the case here as well. No matter what the subject distance or the lens (I also tried this with an old 105/2.5 AI-S) I can find a better focus point if I search manually versus the autofocused image. The images obtained from autofocus with TC-16a are sufficiently off from critical focus that the images are unacceptable.
@Oliver – this is speculative, but it feels like the autofocus systems may be slightly out of sync between the TC and the camera. Aside from the D300 focus adjustment, any thoughts on the possibility of a way to get the TC to speak the same distance as the camera? If I stuck on a 70-210/4 I’m sure the focus would be correct. Why should this be any different if they share the same cpu?
BTW – thanks for this page in general. I would not have attempted the procedure without such a detailed walkthrough.
October 30th, 2009 at 22:21
The job is done! The servofocus with 500mm f/4 P is correct (very very accuarete and fast) on my d300 and d700, and also the F/aperture is correct (from f/4 to f/22). The exif declare (as expected) 70-210. I’m very happy. Thanks Oliver and thanks to All. But… the live view is not usable. This anomaly was also noted by others? It’s possible solve this problem?
October 31st, 2009 at 13:04
@Walter: I’m glad to hear your 500 f/4 P is focussing correctly, after others have been experiencing problems with this lens.
About live-view, I did not know about that yet, and I don’t remember even trying that. As soon as I have some time for it, I’ll try it out, and see what happens. Does live-view not work at all, or just focussing during live-view? did you try tripod mode and handheld mode?
October 31st, 2009 at 15:52
@Oliver
When I set the live-view mode (in both modes)the shoot is blocked.
October 31st, 2009 at 18:11
Many thanks Olivier for this modification guide. I followed all the steps and it seems that it jut works ! although not deeply tested, it gives good results with the first standard combination tried: an AIs 105 f/1.8 and the D700. AF is very fast (more or less like with the 85 f/1.8 AFD).
Second test: D700 + Nikkor f/8 8mm circular fisheye. This lens is not only MF but fixed focus. You can change the focal plane using a 50mm + reversed 50mm + rings, to avoid the mirror lock-up on your D700. Add the modified TC-16A and change the reversed 50mm by a reversed 28mm to recover the original FOV (thus compensating the 1.6X effect of the TC-16A) and you get an AF fisheye made in 1962 delivering decent results almost 50 years after !
November 1st, 2009 at 07:58
Hi Oliver,
I wonder after : the modification, will the TC still work with it’s “intended” bodies ? (i.e.) F4/F90 and so on?
November 2nd, 2009 at 00:37
Hi Oliver,
I’m going to do mine today
will this work with D90
and after the modification, will this still work for it’s intended earlier bodies ?(F4/F90 etc )
thank again
November 6th, 2009 at 19:03
FWIW, I attempted the full mod – shifted contact #3 to position #6, as well as lifted pins P112 and P113. I was very careful with the gold springs, soldering, etc., but still managed to brick the electronics of the TC-16A. I suspect that the Kapton flex-PCB tore near the CPU when I removed it for the pin mod – I’d advise extreme care and very gentle removal (with an exacto knife or similar) of the glue that holds the PCB to the plastic plate, before attempting to slide the PCB out for the pin mod. Otherwise, there’s a fair chance that the PCB will tear.
Anyway, the TC-16A still works in full manual mode (manual focusing and metering) on a D50 or similar, so it’s not a dead loss. With a manual 300mm f/4.5 ED-IF, I now have a hand-holdable manual 480mm f/6.8 with incredibly sharp IQ and colour rendition when stopped down to f/11 or so, and I’m satisfied for now. I’ll get another TC-16A later, for another attempt at the AF/metering mod – I suspect that this could be a killer hand-holdable long-lens combo with the 400 f/3.5 or 400 f/5.6 EDIF.
November 7th, 2009 at 17:00
@michael: The mod should work with the D90 see the “D100 specifics” and the further mods described in the comments. It will work on the F4/F90, etc, just like on the new cameras, it just won’t work the same way it used to work. It will have the same features and limitations on the old cameras that it has on the new cameras.
@Sivasankar: Sorry to hear that. You might be able to fix the tear by scratching the surface of the traces on each side of the tear, and bridging it with some solder. It won’t be flexible anymore, but it might work again.
November 15th, 2009 at 19:14
this is amazing stuff. really you guys are geniuses.
I have a TC 16A that i came with my F4. and I was very surprised when i realized that the auto focusing happens on the TC and not the lens. then i ran to grab my d700 and 300 4.5 lens but was really disappointed. It did work on F5.
Anyway I ran into this website and have the TC already open. lol. Well will have to run to home depot to get some tools (the drill bit).
HOW DO YOU SOLDER SOMETHING THAT FINE? I can barely see the spring. Any tips, suggestions? The soldering iron i have by no means is “very fine”? what soldering iron do you guys recommend?
Please help me out with any suggestions you have to make this work it as close to as the real combo i wanna use. I want to use this TC with 300 f4.5 ED IF on a D700.
one last question.
Just curious will this modification make this TC lose AF on F4 and F5? which I would not really mind as much as long as it will works with the D700.
thank you all
November 15th, 2009 at 21:33
@xhevi: thanks :-)
The soldering requires a somewhat fine soldering iron. But with steady hands and some soldering skills, you can even use a less fine tip… but the big soldering guns won’t work. A little finesse is required, as the wire with the solder blob on it can’t take up too much space, or it won’t fit in the casing anymore.
The TC should also work on the F4/F5 after the modification. It works differently, but you probably won’t notice the difference under normal circumstances.
November 16th, 2009 at 01:58
DONE
I just got the d700 to auto focus with MF300 f4.5 ed if. works great. but by the time i am done is night time so i cant really go try it out with lots of light.
boy this conversion need patience. but is worth it. it took me a while thou. well most of the time I was looking for one little spring that had ended up inside the TC. turned everything upside down then decided to open the whole TC. and found it there. a lot of time and PATIENCE took putting it back together not only the CPU bloc but also the TC (don’t mess with the TC body if you don’t have, it just take more time but compared to the CPU modifications is a piece of cake)
I dint have a very thin isolated wire. i managed to solder the spring with a piece of wire and had the wire pass the circuit then back in front to solder it to the circuit. my soldering was not all that so it was on the way of he pin moving freely. i did cut a couple of threads from the spring to make it shorter to leave room for the soldering tip.
I also cut the P112 and P113. When the is lens wide open I get FEE error. if I close it down all the way the camera reads f8 instead of 32. So I had to go to the menu and changed my aperture to be controlled by the aperture ring.
YESSSSSSSSSSSS.
Wide open it reads 4 instead of 4.5 but thatch no big deal. and from 5.6 to 32 works like a charm. It stil works with F4 and F5 also.
One day I would like to be able to control the aperture with the dial. I know you guys posted a lot of info here, will read thru again to see if the solution is there.
I was thinking to buy a new AF TC but will stick to this one instead. and keep an eye on other (longer) telephoto lenses. this modification will bring back a lot of old manual photo lenses.
I am very exited about this.
WOW. It would also try to auto focus with the Ronikon 650-1200mm. the only object for the lenght is the the building across the street, and is already night. will give it a try tomorrow. I know i will not get tack sharp pics with this lens but hey that is a lot of reach.
The only complain i got about this TC is that the view finder gets quite dark. but in sunny days should not be a problem.
other tools i used:
Swiss army knife to make the new hole. lol. the hole is a slighty bigger but still very good for the tool used. i suggest the get the drill bit.
exacto knife to remove the circuit board.
happy shooting guys.
thanks for this wonderfull idea.
November 22nd, 2009 at 01:37
Thanks for the great right up :) Sorry this may be a daft question but I have Nikon D40 that only takes AF-S lenses. It can not meter none CPU lenses and has no AF motor built in the body. I was really hoping to try one of the compact mirror lenses would this allow me to do so? Or does it still have to be a CPU lens? Thank you
November 22nd, 2009 at 01:55
Arg sorry have found out it will not work on it. Thanks again :)
November 22nd, 2009 at 13:51
@Thomas: I think it will work, the metering that is. Of course Autofocus won’t work, as it only has the “screwdriver” type of autofocus, and doesn’t have a built-in Motor. But with this modification, the TC-16A becomes a CPU lens – or rather pretends to be one – so the camera will do the metering as it would with any other CPU lens, no matter what lens you put in front of the TC.
November 28th, 2009 at 16:48
A few subjective observations:
On a sunny day, the manual 300mm f/4.5 ED-IF + modified TC-16A is subjectively better than an AF 300mm f/4 + Kenko DG Pro 300 1.4x TC at all apertures from f/8 to f/22, on a D50 DX body. The manual lens really shines at f/11. The AF lens is better wide open at f/4 to f/5.6 than the manual lens from f/4.5 to f/5.6. YMMV on an FX body like the D700 – the TC-16A did not have a great reputation for edge-to-edge sharpness on film bodies, but is surprisingly good when cropped to DX sensor size. There is less noise/speckle with the manual 300 f/4.5 + TC-16A combo than with the AF 300 f/4 + Kenko combo at similar ISO/exposure settings. I suspect that this could be due to better Nikon glass in the TC-16A compared to the Kenko, but it could also be due to the internal 39mm filter on the 300 f/4, which needs to be very clean on both surfaces to reduce speckle. I’ll do another set of subjective evaluations later, with the lenses swapped to get a better idea – but the short story is that the 300 f/4.5 ED-IF + TC-16A is very, very good for the money on DX bodies when stopped down to about f/11.
December 2nd, 2009 at 09:11
I have successfully modified my TC-16A followed those instructions above. Thanks to all.
@Alex and Bruce:
I have solved the miss focus problem. It is true that camera body will adjust its focus calculation according to the focal length.
With basic modification of just change the pin order, I get constant focus offset in front of the subject. The EXIF sais 8mm of focal length, but I have mounted an 135mm f/2.8 on the TC (which equals to 135*1.6=216mm), the wrong focal information leads to the miss focus.
Fortunately, by configuring the TC to 70-210/4 (neither P112 nor P113 connected) configuration, the problem diminishes! And to my convenience of using 135mm f/2.8, I connected P100 P101 P102 to the ground and set the focal length to 210mm. The Gray Code accordingly with 70-210mm focal length is:
P103 P102 P101 P100 (1-no connection 0-short to ground) vs focal length
0000 70mm
0001 75mm (Approx)
0011 81mm (Approx)
0010 85mm (Approx)
0110 94mm (Approx)
0111 101mm (Approx)
0101 109mm (Approx)
0100 117mm (Approx)
1100 126mm (Approx)
1101 135mm (Approx)
1111 145mm
1110 155mm
1010 169mm (Approx)
1011 181mm (Approx)
1001 195mm (Approx)
1000 210mm
Further more, with the configuration the camera can control the aperture via dial, and can work on A, S, P and Auto modes, with matrix metering and build in TTL flash etc., which brings more flexibility.
Those tests are carried out on D80 and D50 body.
December 2nd, 2009 at 13:10
@Murphy: Thanks for that Info! I’ve been meaning to test the gray codes for the different focal lengths, but I guess now I don’t need to :-)
Maybe I’ll test the gray code for when it is set to the 35-70mm/3.3-4.5 – no need to check them when its set to the 50mm/1.8 ;-)
December 6th, 2009 at 20:10
Hi, thanks you for posting this wonderful mod. I have followed successfully your instruction. It’s working fine on my Fuji S5 but with a front focus with every lens attached. Any suggestions? Does the focal lenght mod correct this issue?
Thanks again for your great job!!
December 8th, 2009 at 16:36
I would like to thank you for your time publishing the above and sharing your knowledge .
I did the above mod. as moving the pin No. 3 to the unused pin 6 and I was having difficulties to re-assembling it back However after several trials I did do it as well , But it seems it’s still not functioning at all ! ,It’s not even giving me any error on my D3 ! there is no sound or movement here ! , on the other hand I did the camera setting as you mentioned for D3 ( to disable the aperture function so it wouldn’t be controlled by the dial ,, with no luck !! Any hint or am I missing something here ?
Regards ,
December 8th, 2009 at 16:38
Oh ,, My lens is 600mm. AIS P
December 11th, 2009 at 04:56
@Jean: Exactly, the focal length mod dose almost correct the bias on Nikon D50. I use term ‘almost’ here because I have tried every configuration of that chip, and find out that every combination, except the original one (TC-16A, 8mm f/1), makes no perceivable difference in precision of focusing between them. That is to say, focal length modification will correct the bias as far as a same amount.
However, I noticed that with longer focal length configuration (210mm), the TC seems more sensitive to low luminance scenario, other wise the element in TC bounces forward and back more likely during the focusing, especially when mount with a long lens (exp. 135mm f/2.8). When mount with a sorter lens (exp. 50mm f/1.4), such behavior still exists only seems of a less extent.
December 13th, 2009 at 22:31
Thanks for sharing. My two cents: This is the way i did the mod. Instead of soldering the thin wire, I drew a conductive path with a conductive paint on the back of the flexible PCB and a conductive area for the spring. It works very well and it’s reliable.
@Murphy Li thanksfor these further explanations, I’ll try it.
December 15th, 2009 at 02:28
Jean’s idea sounds great, I’ll try it too and report back. By the way, if you can’t find a circuit paint pen, you may also try the paint that comes with rear window defogger repair kits – it’s also a type of conductive paint…
January 6th, 2010 at 09:00
After several dedicate tests on TC-16A, I noticed that its focusing accuracy is still not as perfect as expected. Especially when it is working with my 135mm f2.8 series E. The focus position is always little bit near than it should be, even though I have modified its circuit to be identified as 70-210mm f/4D. Today I find a tool that can extract so many details of EXIF data from file, that might help us find a way to solve the problem above or even further.
It can be find free via http://www.rottmerhusen.com/objektives/lensid/nikkor.html
From every image file taken with TC-16A via the tool I find that:
Focus Position : 0×30
Focus Distance : 0.02m
Since the TC behaves as a fake 70-210mm f/4D, it will certainly not transfer proper distance information to the camera. But 0.02m is a distance too far from the reality. I guess that the distance has relation to the focusing algorism, and if so, a proper parameter might able to make focusing more accurate. My suggestion is find out how the distance is configured by the chip (probably gray coded like zoom as well. P111 P110 P80 P81 I guess). If it is not as simple as expected, I prefer hacking the chip by observing the waveforms through the lens contacts, and program a workable MCU to replace it.
January 8th, 2010 at 02:33
Just an update. I actually modified my TC-16a and after a few HOURS of trying to get everything right I was able to put it back together again all intact.
I slapped on the 400mm f/5.6 on my D700 and focused on whatever I could find. It worked great…periodically. I was shocked considering my working f-stop was f/9!
Unfortunately the lens wouldn’t focus consistently and I found one of the pins was sticking inside the hole and the only way to get it out was to disassemble the unit again.
Reluctantly I opened the case and when I did all heck broke loose. In the end the metal tore off the ribbon and that was the end of my show. In fact, I also ended up losing a spring in the process. I tried makng my own but I couldn’t fine spring wire fine enough to make it with.
It’s taken me months to report this. Maybe I’ll put the lens up for auction as a parts lens, but I won’t do that until it try one more time. I have a new TC-16a coming in the mail. I’ll keep you updated.
January 13th, 2010 at 16:37
Second time was a charm. I got it working. I first tried tracing a circuit so I didn’t need to solder, but that didn’t work. I ended up soldering a wire to the spring.
Since I had extra parts I decided to see what would happen if I left a pin in position 3 along with position 6. The unit appeared to function properly, until I realized that I couldn’t lock focus on an item and reframe. Didn’t matter which AF mode I was in either. Plus it appeared to hunt and not lock focus on anything. So having pin 3 and pin 6 confuses the camera. I obviously took pin 3 out and now the converter works again.
Thanks to everyone for all your help!
January 13th, 2010 at 18:17
Murphy, thanks for your great observations. I have a question about your Dec. 12th finding though. You stated that in order to get a 210mm focal you remove the pin for p112, p113 and p103. The other pins, p100, p101 and p102 are shorted to ground. What does that mean? Do I disconnect them and run a wire to pin 20 (gnd)?
Thanks in advance.
January 21st, 2010 at 09:26
@Nathan, you were right. To config TC-16A to be 70-210/4 at 210mm, all you have to do are two steps:
1, Disconnect P112, P113. This makes the chip behave as 70-210/4.
2, Connect P100, P101, P102 to pin 20 (GND) with a wire, and leave P103 unconnected. This makes the chip sais 210mm to the body.
PS, I made a mistake in statements in January 6th, 2010 with ” 70-210mm f/4D”. In fact 70-210mm f/4 is a non-D type lens and should not possibly tells the body about an live distance infomation.
January 24th, 2010 at 19:22
First of all many thanks for all the usefull information eveybody gathered so far and especially to Oliver who started with this!!
I bought a TC-16A to get some degree of AF on an 800mm mirror lens. Since my camera is a D80 I’ve done the pin swap as well as the P112, P113 disconnect. Everything works nicely BUT….I found also like some others here that although it focuses quickly and gives the beep, the focus point is always just behind where you point. So I tried all greycodes for the 70-210 setting but no change there. Secondly I tried the 35-70 setting but also there no luck. Focus remains off position. All this did however produce a grey code list for the 35-70 setting:
With pin order 103,102,101,100 and “1″ meaning connected to ground
0001 48mm
0010 60mm
0011 35mm
0100 45mm
0101 35mm
0110 62mm
0111 35mm
1000 52mm
1001 38mm
1010 55mm
1011 38mm
1100 42mm
1101 38mm
1110 70mm
1111 38mm
As it seems not all positions are used for different values, sometimes you get the same result from a different combination (I checked those a few times extra to make sure it was not a connection fault)
Does anyone have an idea how to fix this focus problem? (other than buying a D300 and correcting this on the camera…)
Again many thanks to all of you!!
January 28th, 2010 at 09:28
We can infer from the link:
http://www.kenrockwell.com/nikon/f100AFEr.htm
That such constant focus error may mainly caused by “spherical aberration” of a lens, especially then it is wide opened. Camera will possibly compensate this error by adjust the offset accordingly with a lens, exp. Nikkor 50mm f/1.4d. This assumption is proved by noticing that when a TC-16A with original configuration (neither 35-70mm f/3.3-4.5 nor 50mm f/1.8 nor 70-210mmf/4) result in a more serious focus error. This is because the camera compensates the focus in the wrong direction so that makes the focusing plan even away from the desired distance.
See also here: (a site in French)
http://www.nikonpassion.com/modules/smartsection/item.php?itemid=83
He managed hacking the protocol of Nikon P type lens communications, and is able to program his customized lens chip! It is not too complicated as far as I have read.
I think it is possible to make a customized chip with so many combinations of focal length, aperture etc., and try it on the TC-16A. With enough luck we can find a suitable configuration.
January 28th, 2010 at 22:51
Correcting the EXIF info
Another issue I have been considered is how you can correct the EXIF values on focal length and aperture.
The easiest way I have found is to use the excellent freeware exiftool. If you are a Windows user you can simply download the .exe file and place it on the desktop. Then rename it to exiftool(-FocalLength=800 -FNumber=6.7).exe or whatever values you want to use.
The conversion is completed by “drag and drop” the files or the directory to the icon on the desktop.
Maybe I have been lucky, but I can see no focusing errors using my successfully modified TC-16A on the Nikkor P 500/4 whether I use it on a D300 or a D80.
Soren
January 30th, 2010 at 21:10
Since my lens is a mirror type (aka reflex lens) the risk on sperical aberrations is small. But to rule that one out I tried the TC-16A on my 18-200. And guess what; exactly same behaviour. But now I could see that the deviation is focal length related. On 18mm is almost not noticable, going to 200 it becomes clearer. I used the focus test chart from http://www.FocusTestChart.com to quantify the amount.
Being curious about my other lenses I put all of them to the test with the test chart. It showed that actually all had some degree of back focus. Following what I found on http://leongoodman.com/sergei/backfocus.htm I adjusted the AF stopper in the camera body. The ’special’ tool is by the way just a 2mm allen key…
Now the “normal” lenses are correct but the 16A remains off position. A lot less than before but still…
Thanks for the link to the french site Murphy! I think I’m going to try this. Since I’m an electronics guy I also put the scopemeter on the signal pins but couldn’t yet figure out what the patterns mean.
February 1st, 2010 at 08:04
@Arjen: I will be very careful towards the method of adjusting mirror angle, since the reason of back focus is not there, if the body can actually work well with other lens (exp. 50mm f/1.4D).
The waveforms of serial interface of lens chip is quite simple as can be found in the NEC upd7554a manual, it can be downloaded from the net, or you may leave an email address so I can send you one. By which the patterns you have mentioned can be decoded manually or automatically. Also I am very interested to do such decoding and analysis with you, so it is very pleasure if you can envoy them to me via murphyli [at] 163 [dot] com.
Thank you for your efforts in advance!
February 8th, 2010 at 20:35
Can anyone help? I have a pre-modified TC-16a that apparently worked fine on a D300. But on my D700 I get the dreaded FEE error no matter what I do. Auto focus works just fine – I simply can’t take pictures! Pins P113 and P112 are disconnected; I get the same if they’re connected to ground (ie as standard). It doesn’t matter what lens I use or what I set the aperture to, it’s still FEE all the way. Can anyone make any useful suggestions please? I’m so envious of all of you who have it working on the D700…
I am an experienced electronics constructor; fine soldering doesn’t scare me.
February 8th, 2010 at 20:44
@Giles: pre-modified? Do they make them like that now? ;-)
the FEE error comes up when the Aperture index tab doesn’t correspond to the min aperture defined by the lens type defined by the setting of pins P113 and P112. Read comment number 9 again for the details.
basically it depends on which lens you put on the TC, and it’s aperture range. you have to make sure it’s the same number of stops as the lens that the TC pretends to be (pin 112 and 113 setting).
Before you go and solder anything, try moving the aperture index tab on the D700 with your fingers, or with forcepts or something. And if that works, try using a lens with the correct number of stops.
February 9th, 2010 at 01:59
@Oliver – The lens was modified by a previous owner; I was perhaps a little careless in my choice of language, for which I apologise.
Regarding item 9 – thanks for pointing me back at it, but the finer points still escaped me. Walter (point 34) seems to be saying saying that with P112 & 113 high his manual 400mm f/4 reads the aperture correctly to f/22 – I’d be very happy with that!
Following your suggestion and moving the aperture index ring manually beyond the test lens’ minimum aperture does indeed stop the FEE error, but only when the D700 aperture ring is at a certain position (approximately at the “F” of AF TELECONVERTER”). It’s a start!
The MF lens I’m using for test purposes (an old Tokina 35-70 f/3.5-22) cannot take the F ring that far over because it only stops down to f/22. So I wonder if I am right in assuming that’s because the minimum aperture of the 70-210 is f/32 and so the D700 thinks there’s a problem? Forcing the aperture ring over another millimetre or so seems to make the D700 work, metering and exposing more or less correctly in low light. Perhaps I’m getting somewhere.
So, I looked at the three lens specs in 9) and took P113 low – 50mm f/1.8, max aperture f/22? Guess again; the aperture ring needs to be taken even further round because (I guess) the f/1.8 stops down to about two-thirds of a pinhole.
So, back to the soldering iron and take P112 low instead. Success! Stopping down to f/22 now works, and the camera takes pictures! *does little dance of joy*
I plan to use the TC-16a with a T-mount 500mm reflex lens nominally at f/8, plus some other T-mount MF optics of varying focal lengths.
So I guess the next thing will be to make up a T-ring that’ll force the aperture ring to f/22 and then manually dial up the exposure settings. Not too much of a burden, because I don’t intend to use the AF for complex, variable lighting conditions or
fast-moving subjects.
(So why use AF? Unfortunately I have a heavily astigmatic focusing eye and even with good spectacles my manual focus technique is best described as hit and miss).
So, Oliver – have I guessed correctly about what’s going on here? And is it basically down to the fact that the D700 is such a darn fine camera with sensors and compatibility galore that it’s just that little bit harder to fool than some of its earlier brethren?
I should perhaps point out that my background is in electronics and communications, rather than photography. I take, and publish, a number of quite boring engineering photos in any given year but for me the camera is just a tool to get a recognisable image into a magazine – rather like a word processor is a tool for capturing the text that surrounds the image. That said, I do quite enjoy fooling around and amusing myself with my cameras, and am a sucker for available-light stuff.
G.
February 11th, 2010 at 21:33
@Giles,
well, almost. the AI ring & tab, are only RELATIVE. They are all relative to the max. Aperture of the lens, and not min. Aperture.
however, the camera expects the ring to be set to min. Aperture, so that it can (electronically) control the full aperture range. if not, you’ll get an fee error.
This is because the camera always meters at max aperture, then stops down by a number of stops, relative to the max aperture. it doesn’t care whether that’s 1.4 or 2.8 or 3.5 – these values are only for looking nice in the EXIF data.
That’s why there is no “at f/22″ “at “f/32″ setting, only an “at 5 stops from max aperture” or 6 or 7… and it’s those settings that the camera expects, and you’ll need to set the pins 112 and 113 to match the aperture RANGE of the lens you want to use.
It’s the same for the D300 and the D700 but depends on the lens you put on the TC.
Now of course, there is still the workaround that I used in the main description under “D200 Specifics” (before the findings described in the comments):
The Trick is: go to CSM (Custom Setting Menu) under f: “Controls”, position f5: “Command Dials”. There, under “Aperture Settings” choose “Aperture Ring”. This means you can’t control the Aperture via the subcommand dial anymore (so you’ll want to switch it back when you put a normal AF-D lens on the camera again).
then you don’t need to care about the aperture range (which will be 1 for your Reflex lens – so you won’t find a matching pin setting anyway), and instead you can choose the pin setting according to the focal length, to help the camera determine focus. That way you don’t need to modify your T-adapter either.
I don’t know enough about optics to tell you which setting to choose – I’d try the 70-210/4 setting, but the reflex lens might behave completely different and another setting would be better. With the 70-210 setting, you might want to set the focal length to as long as possible (210mm) using pin P103 P102 P101 P100 settings described in comment # 49 by Murphy
February 16th, 2010 at 01:05
TC-16A on a D2x…
AF only works with the camera set to continuous focus – single shot position will focus but won’t let me take a shot – any advice?
Thanks for the great discussion…rgds Carl
February 16th, 2010 at 12:39
Hi,
Thanks for all these precious info. This is so rare that one can do DIY on photographic equipment !
I plan to use the TC-16A with 300/2.8 AI and D300.
Should I better set the pins as a 50/1.8 (7 stops as the 300/2.8), or as a 210mm (6 stops only, but closer focal length) ?
As I plan to use the lens ring for aperture control, and do not often close at f/22, I should probably do the latter, am I right ?
On the other hand, is similar focal length important ? I mean, the TC-16 AF mechanics are probably very different compared to the 70-210, so is it of real help for the body focus calculations ?
Thanks in advance.
Vertigo.
(PS : I happen to have a recent AF 50/1.8 D. Can I use it in any way for completing the TC-16A modification ?)
February 27th, 2010 at 20:00
I could not wait more ;-) and did the whole mod. It works as intended on the 300/2.8 AI. Now I have a 480/4.5 AF !!
I like the partial autofocus, you still get the feeling of MF, together with precise AF in the end. On the D300 it even works for birds in flight !
Thank you Oliver for all !
March 4th, 2010 at 15:51
Hello,
I have done the modification and after a few tests I have put it back the way it was.
I used the modified version of TC-16A on a D700 and with a 50mm f1.2.
First of all, the modification is by no means an easy task. Do only attempt with the right equipment and only if you feel confident with it.
In my case, even though I was being super careful I managed to loose one of the springs. Luckily I found one to replace it in an old printer.
After the mod the lens does not communicate the aperture to the camera. This generates an error which can be solved by changing a setting in the D700 to allow the camera shot and control the aperture using aperture ring. This lets you shot but the aperture is still not read by the camera so forget about the light metering. It’s back to hand held light meter in your hand or guessing the exposure. Far from ideal.
Now, the pseudo autofocus; yep, it worked, kind of. When it finished the mod and tried for the first time I was quite impressed it worked at all! It’s very cool to see a manual lens auto focusing but…. it was way out!. I get the idea of pseudo autofocus, approximate manually and then use it, but still. It was obviously out when compared to my focusing by eye manually. I was testing this on f1.2 so a tiny bit out is enough to ruin any image with such a shallow deph of field.
From the other comments, I gather that the results can vary depending on the type of lens and camera. It could also be that there is a fault with my TC-16A but I don’t think so.
In my case it is back to the way it was. At least I can use the converter in manual focus which is fine for me.
Thanks for all the effort explaining the process. Pity it didn’t work out for me.
Cheers,
March 11th, 2010 at 00:06
Hi Oliver,
Thanks for this sweet mod. Funny thing with my attempt (using D90 and N70) was that disconnecting P11_3 and P11_2 (to set the chip as a 70-210/f4 and kill the autofocus errors of the default configuration)resulted in an aperture range of f/3.8-25. Also, for some reason, on my chip, grounding P11_3 (to set the chip as a 50/1.8) didn’t work and still shows f/1 on the D90.
Anyway, sticking with my f/3.8-25 configuration and autofocus is sharp when used with a 50/1.8D.
By the way, I ran across the source for your CPU pinout diagram: http://photo.net/nikon-camera-forum/00956N
March 12th, 2010 at 12:43
@Tazman, thanks for the Link – the thread has become even more interesting than the last time I saw it, it was revived in 2008, and some valuable info was added!
I finally added the source to the diagram.
Maybe I’ll get to work on a new (programmable) chip for the TC-16a at some point, where everyone can select the lens they want to use… when I have some time.
April 20th, 2010 at 23:54
following the excellent instructions provided here and in the Mostert PDF, i successfully converted my tc-16a last week and without the need for any wires or soldering. instead i used copper tape (the conducting adhesive type) to create a new contact pad for the relocated pin and connect it with the old one across the top of the contact box.
i locked my cpu @ 50m/f1.8 by lifting P11-2, which was a royal pain to do. when i do the next one, i’ll just cut the pin on the cpu as rejoining it later if required would be far simpler.
if you are planning to use a range of lenses with the tc-16a, i don’t see the point of locking the cpu at anything other than f/1.8 as i’m not sure the camera AF system takes any notice of the cpu-reported focal length.
with the cpu @ 50/1.8, the AF works nicely with all my lenses (regardless of focal length) so long as i set the lens manually to infinity-focus and accept a shorter minimum focussing distance, which on my 50/1.8 ais nikkor works out at a very acceptable 4ft.
i found that setting the lens focus to less than infinity allows closer AF but that then it only works some of the time and when it fails, the green LED indicates a focus-lock despite the subject under the focus-sensor being clearly not in focus.
to obtain accurate metering with slower (than f/1.8) lenses i apply appropriate compensation which all just works out in S mode. if using A mode i need to set the desired aperture minus the compensation. so, if using an f/2.5 lens in A mode, i apply +1.3 stops compensation and set aperture f/1.8 when i mean f/2.5, and so on … if that makes sense.
April 28th, 2010 at 17:41
Just modified the TC16a (only moved pin 3 to 6. It works fine. Now I’m planning to disconnect P112 and P113 but i’m not really sure which they are. Can someone please mark the m inthe photo of the front circuit print?
Thanks
Bruno
May 6th, 2010 at 01:19
bruno manunza:
take a look at the following image which indicates where pin P11-2 is located. cutting/ lifting this locks the cpu @ 50mm/f1.8. hope this helps you.
http://picasaweb.google.co.uk/lh/photo/ZCajErwjq0-nKMs4s-Z2YA?feat=directlink
May 11th, 2010 at 00:53
I’ve got a TC-19a today. Planned to modify it. I tried attaching it to my Nikon 500mm f8 mirror. And now, I can’t detach it from the lens. Could anybody help?
May 18th, 2010 at 03:27
Hey there.I almost did it.
It works on My D300 but not on the D700.
Any ideas why?
May 18th, 2010 at 03:50
Yea I just changed the command dial to aperture ring. Only then works on my D700. D300 works anyway. Thanks everybody for contributing to this. God bless
May 24th, 2010 at 09:35
Did anyone try to replace the chip with a Dandelion chip? See: http://filmprocess.ru/nikon_spec_en.htm
May 26th, 2010 at 19:13
Thanks Oliver for discovering and sharing how the TC-16A can be converted.
I’ve just modified my TC-16A, bought for £20 at Photographica London last Sunday. The only deviations from your instructions are that I made two groves on the back of the pin holder for the wire to pass through, and I used a 1.5mm drill to match the size of the other holes. (Actually I used an 1.2mm drill first, and when it was off centre slightly, I used it to elongate the hole before finishing it off with a 1.5mm drill.)
My modified TC-16A works perfectly with my Fuji S5, without any front or back focusing problems. As expected, some pre-focusing is needed with fixed lenses. However, with the Nikon 50-300mm f4.5 ED, there is FULL AF range from near to infinity at 50mm to 85mm, and progessively limited to longer distances from 105mm upwards. AF was lightningly fast too. I am really happy with my ‘new’ 80-480mm AF lens.
It’s a pity that Nikon did not have the foresight (actually will) to make the TC-16A to work with a much wider range of lenses. It would be great to have the following :
PINS MAXIMUM APERTURE
113-110 Present Ideal
0000 4 13
0001 4 11
0010 4 9.5
0011 4 8
0100 3.8 6.7
0101 3.8 5.6
0110 3.8 4.8
0111 3.8 4
1000 1.8 3.3
1001 1.8 2.8
1010 1.8 2.4
1011 1.8 2
1100 1 1.7
1101 1 1.4
1110 1 1.2
1111 1 1
PINS FOCAL LENGTH
103-100 Present Ideal
0000 70 8
0001 75 16
0010 85 20
0011 81 24
0100 117 28
0101 109 35
0110 94 50
0111 101 55
1000 210 85
1001 195 105
1010 169 135
1011 181 200
1100 126 210
1101 135 300
1110 155 400
1111 145 500
This way, an 8 way Dual In Line (DIL) switch at the base of the TC can be set to match almost any lens.
I think programming the 4-bit processor would be an easy job for someone with the knowhow. Pity it’s not me.
May 28th, 2010 at 00:27
I just saw the Dandelion chip web pages. Very interesting. I too would like to know if anyone has tried it.
Removing the CPU printed circuit and contact block in the TC-16A could be tricky.
May 31st, 2010 at 11:16
Hi Oliver.
Thank you very much for all your time and effort I really appreciate it.
2 weeks ago I successfully accomplished the conversion and made it work with my D300 and D700 bodies.
The problem is front focusing , on both bodies and with all the lenses I try it with.
The main lens I want to use it is Nikkor 400 F3,5 Ai .
I read all discussions , but some of it is heavy for my english and electronics knowledge!
Can you help me with simple advise how to fix it, if possible.
I took it to Nikon SA but the technician there failed to tune it, he says it’s impossible to be done, which I doubt!
They are just too busy for these small things.
The Focus I always get is in front of the image I am focusing.
The fins focus tune inside the D300 doesn’t help.
Regards -Peter
May 31st, 2010 at 11:21
Bi the way the focus worked fine before the conversion on my D2H and F5 bodies.
May 31st, 2010 at 12:58
Having studied the Dandelion, and tested my modified TC-16A with different lenses, I’ve concluded it’s not worth the effort and expense because the TC-16A meters correctly using the lens aperture dial. The aperture indications on my S5 are wrong, so I just ignore them and use the aperture ring values instead. BTW a f2.8 lens becomes a f4.8 lens due to the 1.6 magnification.
My modified TC-16A does not have front focus problems, with all the lenses I’ve tried, including a Nikkor 50/1.2 and a Tokina 300/2.8. Could it be that Nikon used a different CPU in some TC-16s? The serial number of my TC-16A is 263403
May 31st, 2010 at 15:07
Could it be if I had blocked the contact #5 by using the cello tape to isolate the new contact #6 on the conversion?
May 31st, 2010 at 15:09
There was just not enough space for 5&6 to be contact it together !
June 26th, 2010 at 10:41
hi, i am not sure if i understand how to modify the tc-16a. ist it just enough moving the pin´s, or do i have to change the original prozessor from the tc-16a unit? i don´t understand if i just can use the original prozessor unit.
when i modify pin 3 to pin 6 do i have to use the old pin 3 contact and connect this with a cable to the new pin 6? is this right?
thanks greetings maetsches
June 26th, 2010 at 13:05
I have tried taking the chip out of a TC-16A and installing the Dandelion in. I then setup the min/max aperture + focal length and used the ‘5.6 AF/MF’ function to change the chip to an ‘AF’ one.
The TC-16A, however, does not become AF. The in-body motor of my camera does not turn the TC-16A motor.
Using it on a D2X.
June 26th, 2010 at 13:07
BTW, i know that the original TC-16A works with D2X, but I would like to have the aperture dial function instead of using the ring.
At the same time, the TC-16A misfocuses on the D2X. Hence if the Dandelion can do AF with TC-16A, everything else would be great!.
Please update if anyone can get it working.
cheers
July 2nd, 2010 at 20:14
Hi,
The modification of my TC-16 A for my D700 and my old nikkor lens Ai-s 200mm f/2 ed if works very well.
Autofocus works well.
Exposure metering also after cutting the pin P11.2 on the chip and after putting the F9 at “aperture ring” in the Custom Setting Menu of the D700.
Thank you very, very much Olivier.
July 9th, 2010 at 13:54
Anyone has tried dandelion chip with TC-16A and managed to get the AF up n running ?