View Full Version : Time Lapse--Manual or Auto Exposure?
Chris Long October 27th, 2004, 07:45 AM Hi All
I'm going to be shooting a scene in a few days of the sun coming up (not a direct shot of the sun itself, but of its light falling upon objects as it rises).
I'm wondering whether I should set my camera on Auto exposure and let it gradually adjust itself to the light, or whether I should manually set the exposure for the lighting conditions at their peak, near the end of the sequence.
Pros/cons? Ideas?
Thanks
Chris
Kurth Bousman October 27th, 2004, 12:26 PM I think you want to set it up manually so the exposure doesn't vary over the timespan-Kurth
Keith Loh October 27th, 2004, 01:38 PM But the light changes...?
Chris Long October 27th, 2004, 02:07 PM Yes, it's a bit odd. My gut tells me that setting it up manually would bring a better result. In the dark, before the sun begins to rise, I think a manual setting would introduce a truer blackness--less noise. Auto exposure would try to lighten the scene as much as it could, introducing noise.
But setting it up manually in the dark at 5 AM is something I don't look forward to. I'm not sure how I can guess at what the correct exposure setting will be an hour later, when the sun is up. It seems like I could get that wrong pretty easily.
I may have to set it up at a similar time (the morning before the shoot) and make a note of the setting, and go with that.
Auto would make it a no-brainer, that's for sure.
Tom Hardwick October 28th, 2004, 03:39 AM There are good reasons to go with either route. What would be very interesting is to have two cams side-by-side on the same sunrise, one set on manual and the other left to its own devices. The final result all depends on how the day is going to look. I've done many such timelapse shots and I favour the in-between stage of having the exposure locked, but constantly changing it manually (and gently).
The point in your favour is that you can use graduated filters to constrain the too-bright sky and no-one will know the difference. There's no 'correct' exposure in such circumstances - only what you want and what looks good for the mood you want to set.
tom.
Chris Long October 28th, 2004, 06:07 AM I just got in from checking my exposure settings for tomorrow's shoot. Turns out it'll be easier than I thought--pretty much set it in the middle, and it'll be fine.
Thanks for the help and ideas! Hope the weather holds--
Keith Loh October 28th, 2004, 10:01 AM I've done three time lapses and each time I set it on auto. I tried it once with manual exposure sticking it out of my work window but then the cleaning lady came in, turned on the light and I got nothing but black the rest of the night.
Kurth Bousman October 28th, 2004, 03:42 PM People that do animation with still digital cameras always use manual exposure so you do not get varying degrees of brightness on adjacent frames which produces strobing effects. But if you have some doubts ....test both methods - good luck
Chris Long October 29th, 2004, 01:20 PM Well, I did the shoot this morning, and for the first real attempt at a long timelapse sequence, I guess it's alright. But the biggest problem that I hadn't anticipated was with the white balance. It was set on Auto, and as the light came up from the darkness, the white balance changed from a blue to a yellowish tint. Fairly abruptly, of course, because of the time compression.
It was a very grey day, and the sun never actually showed itself. Just cloudiness. Next time, I'm going to set the white balance on daylight and leave it at that...and pick a day with few clouds.
All in all, though, an interesting result.
Tom Hardwick October 30th, 2004, 06:14 AM Yes, lock down the white balance - I should've thought to mention that - most important. In fact you should always switch to the 'daylight' setting otherwise your camera will always be trying to 'correct' for that nasty red sky of a sunrise.
tom.
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