This is my dilemma: I want to eventually be able to model, texture, colour and render a 3d object in Maya and then open it up in all its rendered glory in photoshop AS A 3D OBJECT so that I can then use photoshop extended's 3d tools to manipulate the object into a photograph just where I want it and then raster it to make it part of the 2d photograph. Can I do this?
I've been using Photoshop since 1992, there is very little about its overall functionality that I don't know about. That being said, unfortunately, I don't always keep up with all of their newer enhancements the way I should, so I'm not completely sure about Photoshop's 3D tools. I am curious though if these are true 3D tools, or 2.5D tools. 2.5D fakes out a 3D environment by giving you XY & Z coordinates in a 2D realm. Thus, you would be able to position items in a "3D" workspace, but not truly have full on 3D capabilities.
Now, unfortunately, I don't know of any way to fully render something out of Maya and maintain it's 3D information. Whenever you render something out, you are taking the 3D information and flattening it into a 2D image. Thus, it is most likely impossible to do what you are talking about. BUT, generally, that's not how you would do it anyway.
Normally, you would bring your Photoshop image into Maya, put it on an image plane for the camera that you are rendering from and then line up your 3D model to the photoshop document there. Then, once it's all lined up and pretty you render it out of Maya and then composite it in Photoshop. Or if you're really good at some of Maya's image manipulation tools, you can just composite the whole thing directly out of Maya. I think that Photoshop will give you better tools for the actual compositing than Maya will, however I think you're going to better off lining up the 3D to the 2D in Maya.
Thank-you very much for your response. I had an inkling that would be the case and I've since realised once an image is rendered in Maya is not manipulatable (if that is a word) any more anyway. Your response is greatly appreciated, many thanks. The question this situation raises ion my mind now is that 3d objects can be brought into photoshop and manipulated through PS's 3d tools, i.e. simple translation rotation etc. Do you what kind of files these objects as saved as?