How do I know if it's photo-shopped

Question

how can i tell if a photo i see online is original or photoshopped? like all the photos you usually see on the funny web sites, what guidelines should i use to determine if it's authentic

Answer 1

if those pics are in the web most problably they are edited or retouched  either with Photo shop , gimp or other photo manipulation program.

plain and simple if the photo looks perfect most like it has been retouched.

here is a web site to help you spot a photo manipulated with photoshop.

http://www.boingboing.net/2008/06/02/how...

Answer 2

There is no single simple way to tell if a photo is real or not but there are a few giveaways :

Things not to scale... if someone has pasted in part of another picture check carefully to see if everything is to scale or if - for example - a head looks too big or too small for it's body.

Lighting... if you suspect something has been superimposed into an image check the direction of the light, for example if most things in a picture cast shadows to their right then the light is coming from the left. Check anything that looks suspicious and see if the light is coming in from the same direction.

Mismatched edges - It is very difficult to accurately cut out something from one image, especially if it doesn't have straight hard edges. A person's head is very difficult because hair is very awkward to cut around convincingly. If you suspect someone has been pasted into the photo take a look at their head and see if their hair looks odd around the edges or if there is detail showing through their hair which doesn't belong.