I am attempting to take 2 photos of the same scene with different settings and would like for them to be as aligned as reasonably possible. I'm doing the following to help in that goal:
- I'm keeping the aperture the same and varying only the ISO and shutter speed.
- I am using a (midrange) tripod and a wireless remote, but I fear I may be nudging the camera slightly when I change the settings
- Photographing scenes with no moving objects (trees, animals, etc.)
- Shooting indoors where there's no wind. It's possible the floorboards move slightly as I move around, though I'm usually not moving a lot when taking the photos.
I'm shooting with a Canon 7D and have Mac I could tether it to if that would allow me to change settings without touching the camera.
Currently, I find that when I pixel peep them at 100% on the computer there's a shift. On some of the image pairs it's a fairly small shift, but on a few it's quite large. Because I'm going to be running them through my own software, I won't be able to use something like Photoshop's HDR alignment tools first.
What are some things I can do to improve the alignment of the images I'm shooting?
Update: I gave some thought to what the comments and answers said and made some changes and got some great results! I wasn't able to switch out my head just yet, though in doing this experiment realized there are other reasons why I should anyway. So hopefully I'll do that soon.
I gave some thought to vibration isolation and ended up not only tethering the camera to the computer to control with the EOS Utility, but then controlled the computer remotely from a computer in another room. This completely removed me from the room and seems to have been enough to get the alignment I needed. Thanks to everyone for their help!