Photoshop

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Touching Up A 3d Image In Post


Adding The Background:

To start off, open up your 3D image in Photoshop. If you want to follow along using this exact file, then you can get it here. It's a good habit to right away duplicate your base layer, so you're always working on top of a copy of the original (left click on layer, choose duplicate layer). Then, lock and hide your base layer, just to be safe.

Right away the solid-light-blue-negative-space attracts the eye, so that's got to be replaced by something a little more divided. If you're ultracool then you'll have created the background in 3d and can skip this step, but if your not ultracool then you can do things this way.
Choosing an background image:
The background image is only meant to take up negative space, meaning it should be something that does not attract attention and the more it blends in, the better. For this reason, a blurrier diffused image will be used.

I'm going to choose this picture by 3dTotal's WebGuru Tom for my background, simply because it has elements that work for my piece and Tom will probably get a kick outa this. Now, as it is, this image won't work so well as a background...

 

But after heavy doctoring it'll be perfect! By cropping, rotating the image, blurring, and adjusting the levels I was able to create something that sufficiently broke up the background area for me. (I planned ahead a little with this, so trust me, it should look OK in the end). You can grab this image to work with here.

Creating a background will be a little different in every scenario. You can use just about anything to create something that blend in and no one will notice. In fact, the less it's noticed, the better.

Once you've got your background ready, then copy and paste it into a new layer on your 3d piece. Now open your Channels Palette and hold the Control button while left clicking on the "Alpha" or "Alpha 1" Channel.

This loads the channel as a selection. (Ctrl+click works for layers and masks as well, by the way).

You may need to invert your selection, depending on whether or not your alpha channel had the background as black or white. Ctrl+click will select whatever is white in the channel, which you can see (in the tiny thumbnail in the picture just above) is the foreground, not the background.

If it's necessary to select the invert, simple hold Control and Shift while you tap the "I" key. Regardless, you want a selection of what your background will be.