INTP:
So you want to buy motors without knowing what kind of forces they need to handle. Okay, good luck with that.
Just thought I'd nail down what exactly it is you're working with since details matter before meaningful input can be meaningful. For what it's worth, I already have a setup where centering my lens on rotation axis with good weight balance just needed a ring mount on the lens and a mount hole in the base plate under the sensor.
Ok, let's settle on these ones at least:
Will Nema 17 motors be enough or I should go with Nema 23 ?
Will Arduino UNO be enough for 2 stepper motors controlers, shutter button, LCD something like this, and at least 3 input buttons (in the future) and maybe sound output. If so how many outputs I will be left with? Arduino stuff is very new for me, so if I write something that doesn't make sence - sorry 