I've been working on the so called "Holy Grail" of time lapse and I'm having trouble figuring out exactly how to pull it off.
Method 1 (Fixed settings in the camera)
Do I set the camera to be slightly underexposed or correctly exposed initially and then correct in post? The rising sun is going to easily blow through 4 stops so I was thinking I should set up about 2 stops under exposed. Reverse for sunset?
Method 2 (tweak the ISO as the light changes)
I just tried this method but I wasn't timely on the ISO shifts, due to mosquitos, I was in the pickup killing time and noticed the display on the back of the camera was dark so I got out, quickly tweaked the iSO up, and ran back to the pickup. I did this a few times so my adjustments were infrequent and coarse. Sometimes as much as 2 full stops of ISO and of course that made very large brightness swings that have been difficult to deal with.
In the end I am looking for a good methodology to follow for getting smooth day to night transitions. I've had the best luck with small ISO increments.
Method 1 is doomed to fail unless the brightness of the scene changes relatively little and would be completely hopeless for true day to night.
Method 2 is the best way although I prefer to change shutter speed and aperture to get the best results. I would only change the ISO when night approches and I have only shot into twilight so far. I have found that 1/2 stop increments produce smooth transitions.
(2013-04-10, 19:33)alexnail Wrote: [ -> ]Method 1 is doomed to fail unless the brightness of the scene changes relatively little and would be completely hopeless for true day to night.
Method 2 is the best way although I prefer to change shutter speed and aperture to get the best results. I would only change the ISO when night approches and I have only shot into twilight so far. I have found that 1/2 stop increments produce smooth transitions.
Thanks for the response Alex.
I was trying to stay within the "guidelines" of wide open aperture and adhere to the 180 degree shutter rule (or 1/50th shutter speed), hence adjusting ISO not shutter and aperture. That's not exactly optimum daytime shooting conditions unless I use an ND filter... in fact, it's not possible without an ND filter. Then you have the effect of the ND filter adjustments to contend with. Bulb ramping has the same ND filter issues. My cameras are all set to 1/3 stop increments and if I'm able to stay with the camera (ie not getting eaten alive by mosquitos) I'll use 1/3 stop increments.
I've had not so great luck with the auto settings so those aren't even on the table for me at this point
In the end I'm looking for a "best practice" to adopt.
Hey,You are discussing about what,I am not getting so please tell in simple words so that I can also take part in discussion.
(2013-04-15, 13:50)StreitRobert Wrote: [ -> ]Hey,You are discussing about what,I am not getting so please tell in simple words so that I can also take part in discussion.
Hey Robert,
Are there any terms that have been used so far that don't make sense to you? I'll gladly help with what I can.
I reshot the time lapse that caused me to post this in the first place. I'm still having the same issues but I think that I am getting closer to understanding the holy grail method. This time I adjust shutter speed until I reached my 1/60th limit, then adjusted iso. I tried to do 1/3 stop adjustments but in hindsight I think that I should have used 1 stop adjustments.
The time lapse that I'm trying to render has two things going on. (1) Day to Night and (2) I'm using a Radian and turning the camera into the sun. So, I have the failing light to compensate for and I have the camera movement that causes the light intensity to shift up.
(2013-04-10, 19:33)alexnail Wrote: [ -> ]Method 1 is doomed to fail unless the brightness of the scene changes relatively little and would be completely hopeless for true day to night.
Method 2 is the best way although I prefer to change shutter speed and aperture to get the best results. I would only change the ISO when night approches and I have only shot into twilight so far. I have found that 1/2 stop increments produce smooth transitions.
I found my problem. I allowed a little bit of over exposure when I set the time lapse up. I should've slightly underexposed. As the Radian turns into the sun, clouds pass over, etc the inherent brightness of the sun rises and falls as these things occur. If it's already over exposed there's no good way to level out the brightness because there is no data, especially for the center of the sun and the halo around the sun, once it's time to process the image.
Lessons learned and all that. I'm a little annoyed with myself that I made the same mistake twice...