Reducing Nikon D5100 time lapse flicker
When shooting a time lapse, most people recommend using full manual mode in order to avoid flicker. However, when I tried that, I noticed that I was still getting some flicker.
This was shot using full manual mode, but as you can see there is a fair amount of flicker. I've found out that flicker can be caused by mechanical inconsistencies even if you're using full manual mode. The reason, in the case of the D5100, is because before each shot, the lens resets the aperture to wide open, then dials in to the set aperture. Each time it does this, there's a chance it could be millimeters off from the last shot.
This doesn't matter at all when shooting single shots but when you're trying to take a series of consistent shots for a time lapse, these tiny differences can result in flicker. Unfortunately, the D5100's lenses all function in a way that produce these tiny inconsistencies. There is a way to trick the camera into thinking you have a manual lens that works quite well.
If you compare the two videos, you'll notice the second one is much more consistent. Both use full manual mode, but for the video below I tricked the camera by holding down the lens release button, and slightly turning the lens to disconnect the lens from the body while still being locked in. If you carefully do this, you can get much better results. Make sure you lock the lens back in before you move the camera.