I have LR4 on my PC, but Photoshop CS5 on my Mac. So if I'm working on a raw image file in LR, I don't have the option of simply right-clicking on the image and selecting 'Edit in Photoshop'. What are my options? Export the image from LR in a high res JPG or TIFF, bring it across to my Mac and then finish it in PS? I was also thinking, how does PS edit the photo if I right-clicked it over from LR (assuming I had PS on PC), what kind of file does LR send over to PS, and what does PS send back to LR once I go back to LR?