Yes. I forgot what those were called and was just calling it the "closeup". And as far as I found, there are no adjustable parameters in Designer for the colorbox... unless you know different. Shopping Cart does make a smaller copy of your image for the main thumbnail and the additional images thumbnails, but apparently keeps the original intact and displays it in the colorbox according to the viewers browser window size. All this started because I was seeing how I could replace an image in a pinch directly into the folder in the store online with ftp without opening Shopping Cart. Of course, you eventually need to do it the right way or update that same folder off line the same way. But if you are in a hurry to correct something, it is possible .....and easy.
I guess that's a standard display technique for the colorbox. I really need to play with those, though I actually prefer multiple thumbs with a display window that stays put... though I know that limits your image size. This is my system I customize for most sites I build:http://clydesdalecarriagerides.com/
(click on the photo gallery)
But the colorbox must be ideal for the iPad and similar. I gotta get with the program. Cheers.