Thank you for the advice. I’ve made some changes, but I’ll be honest – I’m not understanding everything you’re saying. I’m very new here, I’m afraid.
However! I have tinkered around a bit with things and have a better setup. Now I can reliably zoom the camera in and out, but only in little chunky bursts. I still don’t know how to implement an axis value.
Here’s the refined stuff, with slightly less headache:
I think I’m closer to what I want, but I’d welcome more input.