Is there a way to temporarily adjust the overall opacity of a model? This would be very helpful when aligning a model to a backplate. I'm trying to replace part of a product photo with a new piece that I'm rendering, so I'd like to get the alignment as close as possible, before fiddling in Photoshop.
Not really.
Have you tried using the ground grid?
There's a slick trick that may help. I had a similiar situation of precisely fitting a new CAD model into a client supplied backplate of an operating room. The new product was to replace the old "real" one.
I imported the new SolidWorks model twice, with each in perfect alignment with each other using the import settings. Then I applied an "X-ray" to the second model (anything transparent works, like glass, etc.), hid the first model, and adjusted everything to suit, since I could see through it. This did include positions, camera, FL and the like. Then I showed the first model and readjusted it to the first. Hide the second, and you're good to go.
Be sure to save everything!
Also, I then used the second model for a clown pass, making life easy in Photoshop.
Bill G
I like that!!
that be clever thinking my friend :D