The best way to get decent side pics of your dog is to tether them to something, and then toss a treat or toy far enough away that they can see it, but not close enough that they try to get it... then snap pics as fast as possible.
As far as I know they don't have to be purposefully stacked, just as long as they are clear recent pictures.
And I have no idea about the color difference...
If you have to ask, you have a mutt.
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Multiple Dogs Does Not A Kennel Make