I put them on a white piece of cardboard that you get in a craft store. But I think my white balance isn't to great, because the board looks a light blue.
I like these photos as they are, but I can always make comments about ideas for photography.
The white looks pretty good on my computer. The white of your photos wasn't as perfect a white as that of the KS.com background, but it wasn't far off either. If you're seeing a blue cast that's strong enough to be bothersome, you might need to check your screen settings.
Another thing you could try would be getting a table with a lightly frosted glass top and putting the white cardboard on the ground under the table. That way, you'd get the same nice contrast with snakes against a white background, but you'd eliminate most of the effect of the shadow on the cardboard.
Another trick would be to get a second piece of white cardboard and set it as a reflector to soften the shadows.
I might also try this same shot over a piece of black or blue velvet.
These snakes are so beautiful that all you really have to do is point the camera and take the shot to get something worth seeing. However, shooting these guys with a great setup would be fun. If I ever get a camera like Brian's and make it to that neck of the woods, I'll have to try my luck.
Bill
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It's not how many snakes you have. It's how happy and healthy you can keep them.