
You can tell that a picture is credible or not by looking at the source. If your ever in doubt about if a picture is credible or not ask yourself: does the picture look professional? Is the picture from a source that produces well know pictures?. Or does the picture have errors or things that look out of place?
Many people have diffrent beliefs about what is exceptable when it comes to manipulating photos. In my opinion manipulating photos is okay in many diffrent aspects. It's okay when your taking a school photo and you have an unexpected bump on your face, in art, and for entertainment. I also believe something controversial. I believe it is okay to manipulate photos when selling a product. Many makeup companies sell their makeup beside the picture of a "flawless" face and many of the headlines say "Unmistakably Beautyful" or "Want Beautyful Skin." People believe that this is false advertising and deception but i dont. I believe that its fine. This is becasue if you put the face of a regular looking person on the cover of a makeup product box then most likely the product isnt going to be sold. Think about it; people wear makeup because they want to cover there normal face and make it look better then it really is. So why would someone want to see a imperfect face on a bottle of make that they want to make them look perfect?
A good way to be able to tell if a photo is fake is to see if anything in the picture is inconsistent with the image discription. Another way is by looking to understand the image formation properties of a camera. If you know that then you know when a picture is real.