how to tell if its edited?

[MaRtIe]

hey guys, i know it might seem a stupid thing to ask.. but is there any way i can tell if someone edited a picture in photoshop?

[WASD]

Look for clashing hues, missing or poorly done shadows, jaggy edges... Depends on the picture too. What kind of material are you talking about?

[einCe]

open it in photoshop, duplicate the layer and set it to difference. if the image stays the same its been edited

[Vapor]

Look for clashing hues, missing or poorly done shadows, jaggy edges... For a definitive answer, that does *NOT* work! A lot of in-camera processing (such as noise reduction + sharpening) can deliver effects like that.

I do what einCe does, just only for JPEGs. Everything else is kind of unreliable with that method.

If it's a SS you're wondering about, GL, it's not hard to make a perfectly flawless mock-up and einCe's method usually returns a zero difference result. :(

[Overconfidence]

open it in photoshop, duplicate the layer and set it to difference. if the image stays the same its been edited
Which do you set to difference?

[InSanCen]

open it in notepad (Or wordpad if it's a fair size)... the first few lines should say photoshop if it's editied (Dunno if it works for other progs)

[Timmay]

Yep I just tried that now and it works.

[einCe]

Which do you set to difference?
the copied one