Often when I capture timelapse sequences they seem to have a "beat" to them, an almost regular shake to them. Any thoughts on what would cause this or how to prevent it? It does seem to be more prevalent when the tripod's on something softer like dirt as opposed to a big rock or pavement, but if it was just the ground squishing I wouldn't expect such regular movement.
And for those tinkering with DNG file internals, I checked and the Active Area and Default Crop Origins are constant.
Chad
If you say it's regular, check if the lens stabilization is on. When on a tripod, the lens stabilization feature should always be turned OFF, else it'll likely introduce some unexpected shake.
If that's not the root cause, try to experiment on a controlled environment first (say, set the camera on a table at home) and then a different tripod.
All the best and happy timelapsing.
Filipe
Some stabilizers are prone to random movement in OFF position. Sigma 18-125 OS is such a lens. Not the best choice for timelapse. You may want to use the "lens twist trick" if your lens works this way.