The top and bottom image in the first post look different in size
The top and the middle image are also different in size
The middle and bottom are also different in size, with the bottom being the largest
I am assuming that you are not resizing the images that you took snapshots of and uploading them without resizing
This leads me to believe you have your browser zoomed in more than 100%, and that you might also be zoomed in more than 100% on photoshop or whatever editor you use
Without showing the full screen on the editor, I can't say for sure whether or not that is the case for the editor
"Ctrl +" will zoom in, and "Ctrl -" will zoom out on the browser, keep an eye on the top, it should tell you whether you have it at 100% or not