Quote:
Originally Posted by DavidTrap
how they transition from day to night.
DT
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Well, this is known in the timelapse trade as the "holy grail". Flicker free transition from day to night requires (apart from Bulb mode) the "lens twist" trick at small appatures (to prevent flicker) and exposure time, ISO and Apature change. This is all not possible right now automatically, the closest you can get is manually with a "Little Bramper" controller, or automatically (both without auto lens twist) with literally only the "Vandergraf Hart attack Machine", and you cant buy them, theres only 2 in existance
. The Vandergraf Hart attack Machine will have auto lens twist in the future though, which hopefully then acheives the holy grail, Im working on it
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Quote:
Originally Posted by multiweb
Well I think I got it now. My intervalometer was actually set to 20s so I stayed conservative with room to spare. All the shots just after sunset range between 1/30 to 5s. Then all of the sudden they double up in a very short period of time: 8s, 10s, 15s and even a few at 25s and 30s. So that's when I went over. The camera stayed on ISO 200 in automatic mode. When I switched to manual ISO 1600 then 10s subs were back to be shot every 10s, same as the beginning. If you look at the stars just when they start appearing within the clouds they're going slow. Then then accelerate (25 to 30s shots) then slow down to the same speed again. So it's working. I just have to avoid any subs bigger than let's say a 15s shot and I should be good to go. I'll test again tonight. Seems that the change in light is not linear. It starts slow then drops really fast.
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Yes, make sure the interval is always longer than the longest auto exposure time. Light change at sunrise/sunset is fast and non linear. With a bit of practice, you should be able to make iso/ap changes at appropriate times to keep the exposures less than 10 secs and fix the histogram changes in post. If your using bulb mode (with an intervalvometer) though,you might like to use the "lens twist" trick whlist the lens is at f22-f8 if you can to avoid flicker, althought at fast exposures times, flash feedback is also handy but hard to impliment as you then need a way to time exposures from flash socket output after exposure actuation.