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Bulb ramping

Posted: February 11th, 2021, 6:33 pm
by SWIMLAKER
Hello Oliver,
Sorry, I don’t find the auto ramping thread I was reading last night...
My question is, have you guys figured out bulb ramping? Do i still need to do post-processing of my TLs ?
TIA

Re: Bulb ramping

Posted: February 15th, 2021, 11:13 am
by Oliver
Hi,
I split your post from the very old, unrelated post in BUGS/ISSUES, as it's really a feature request ;-)

No, we have not yet implemented bulb ramping, but we are one step closer to it, since we've implemented almost everything needed for Bulb ramping in firmware already, in our Long-exposure feature. Bulb ramping will require one or two more key components, which will still take quite a long time to properly implement - translating the values returned by the Algorithms to the correct exposure times. The EV-24h Algorithm is based on the EV meter, which only returns values in 1/3rd stops. Since we smooth those values, we do actually get more fine-grained EV values than that, so we should be able to get this working without too much additional work. What we will need to add is to always adjust shutterspeed whenever we adjust any of the other two settings, since they'll still be limited to 1/3rd stop steps, or limit Bulb ramping to only allow ramping shutterspeed.

The LRT based Algorithms however work in such a way that the values we get from the Algorithms are completely unrelated to actual EV values. Instead, whenever we get to a certain threshold, we need to adjust settings by 1/3rd stop. We could reduce that threshhold and also reduce the adjustment value, but it will still result in jumps, albeit less visible. True bulb ramping would be to have a perfect amount of change for every single image, and that simply doesn't work with the rest of this algorithm.

Re: Bulb ramping

Posted: February 15th, 2021, 4:35 pm
by SWIMLAKER
Okay, thanks!
(sorry for posting it to the wrong topic, I’m new to this platform, it was rather addressed to you, than to the topic..).