Someone suggested earlier in this thread to use a program to compare two different files, but there's a less technical way if anyone has two copies and photoshop on hand:
If you load an image in one layer and then another one that is almost identical in a layer on top of it and set the layer mode of the top one to 'Difference', then the things that are different between the two layers will show up and everything else will be black. Even if noise is added to the picture, it's pretty easy to see differences
See the example below
If you load an image in one layer and then another one that is almost identical in a layer on top of it and set the layer mode of the top one to 'Difference', then the things that are different between the two layers will show up and everything else will be black. Even if noise is added to the picture, it's pretty easy to see differences
See the example below