James, Peggy Sue,
sorry I didn't respond sooner but I've been busy shooting since the Florida Circuit began last weekend -- 13 shows over 16 days. I've gotten several requests for candids, beauty shots, portraits and action shots so I'm running around quite a bit.

The process works fine with any solid color but the reason that blue and green work best is because those colors don't exist in most subjects -- people or dogs for example -- so you can identify the edges easier and not lose any color that might exist in the dogs' coats.

There are lots of ways to do this -- and it would take a manual to describe it in detail -- but, in a nutshell, we create a new document with a transparent background (File/New/Background Contents = Transparent) and then select all of the image we're working on and copy/paste it as a new layer over the transparent background.

We then Select/Color Range to select the background color and Edit/Clear to erase what we've selected. Now, you have a lot of adjustments you can do within the Select/Color Range menu in terms of getting all the color and doing some Refine Edge to get the results you want. Usually, you have to do some manual work with the eraser tool to get them as clean as you want. But this process gets rid of most of the green/blue background while leaving you your subject(s) against a transparent background that can be replaced with anything you choose.

As I see it, the chroma backgrounds (blue or green) make color selection really easy and, since they don't exist in the real world, they won't be cleared from your subject when you select those colors. White, black, etc. might exist to some extent in coat colors.

Anyway, that's how we do it. I'm sure there are better/more efficient ways of getting the same result but this seems to work for us.

Good luck!

Jim