Just FYI, PNG is part of the HTML spec, I believe since HTML 3.x but for sure since HTML 4. It's an open standard and OSS programs are big on supporting open standards :) Gimp will work great with PNG. The other great side of it is that PNG has built-in compression that is lossless so you get image files that are almost the size of JPG but without the degradation in quality. Lastly, because PNG compression is lossless, you can open a file, edit it and resave it without generation loss. If you do that with JPeg you end up with visible artifacts after 4-5 saves.

One thing you might want to consider though is that if you need reflections in parts of the subject to shown you will need to load that BG inside studio, apply it to a plane and place it around the subject so that eyes/glasses/reflective areas catch the reflection. This will help in "selling the shot" when you compose it in Gimp.

Good luck.

Paolo

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