LiveLens active lens mount for Canon EF lenses
This is what I have. I have mounted my very basic lens that was attached to my DSLR and I can see inside the lens. I mean my viewing window is right in the middle if I divided the screen by 9 rectangles. How do I troubleshoot this one?
If I am reading this right, it sounds like you are seeing the inside of the RedRock. Collimation is the fancy term for setting it up right. Also, I forgot to ask, but are you using the RedRock add on that flips the image right side up into the camera or just the M2 by itself?
Adjust your camera zoom until you only see the image plane without vignetting. Once you know it, jot down the Z number in your display so that you have a reference point when attaching the adapter. Once you have set it, turn the zoom ring off (if possible) and tape it in position with camera tape (even if it can be turned off).
Once that is set, turn the adapter off and wait until the ground glass stops spinning so that you can see the grain. With a bright-ish background, adjust camera focus until the grain of the glass is clear and sharp. This is your back focus, tape this off each time you setup the Red Rock as well to prevent it from drifting while you are shooting.
I think the Red Rock also has a collimation feature on the mount ring (between adapter and camera) that adjusts the distance between the image plane in the adapter and the image plane in the camera. I've never used that feature for optical adjustment, I've always just locked it down and set backfocus on the camera.
I have worked with DPs who lock the camera aperture wide open and only make adjustments at the outer lens, and I have also worked with DPs who will make minor adjustments to the camera aperture on the fly - which makes things interesting as an AC since you have to be diligent and keep track of what your DP is fiddling with during each shot.
Second Question:
When we say 35mm lens, we mean format not focal length. You can get any focal length (18mm, 24mm, 50mm, 85mm, etc) prime or as indietalk mentioned zooms as well. The adapter you have is setup for 35mm still format lenses (as opposed to PL mount 35mm Cine lenses or medium format still lenses, or whatever.) The kicker is the ring. Since you have the Canon EF mount for the red rock, those are the lenses you should seek.
