How can you tell if an image is photoshopped or not?

[ayoub5FB3]

Hi There! i'm a freelance and buyer on fiverr but when i hire someone for phoptoshop work. How i can reconize photo it is photoshoped ot not?

[Trevor.Dennis]

I've read articles on image forensic software, but I don't how well it works.  It's not s difficult subject to research though

A quick guide to digital image forensics in 2020 | CameraForensics

[ayoub5FB3]

Thank you so much, My problem now solved by your guidence

[D Fosse]

There's no clear answer. A pixel is still just a pixel. If it's well done, taking care to avoid the usual clues, you can't tell.

An obvious clue is inconsistent lighting. This is the most common reason a faked image looks fake. You see this everywhere. But that doesn't necessarily mean it's a composite. Often it's just bad exposure correction with uncritical use of masking - the classic is masking out an underexposed subject to a white background.

In the link Trevor posted, I notice the implicit assumption is jpeg. Jpeg compression has a clear fingerprint and I assume forensic software can easily pick out inconsistencies. But if you composite PSD/TIFFs, and then make a jpeg at the end, the pixel structure will be perfectly fine and pass the test.

Cloning will obviously leave repeating patterns. So don't clone.

Then there's metadata. That's more tricky, since even a copy/paste will leave a trail. But there are ways around that too. Export strips all metadata, or you can use exiftool to edit metadata.

Bottom line: if you really want to fake a photo without a trace, you can do it. But most casual users will make mistakes or overlook something.

[Trevor.Dennis]

Dag, you might be right about the JPG limitation for forensic image editing detection, but in all probability it is going to be a JPG that is in question.  I see there is even an online tool called FotoForensics.  I have not tried it, but it might be interesting to test its abilities.

FotoForensics

[Chuck Uebele]

On some doctored jpg images you ca. Use PS to find the edit. This works if someone composits two jpg images that were saved at different compressions. You can reserve the image at different compressions then combine one of the saved images with the original, using difference blend mode. There well be a visible difference some times between the two composites areas. One of the little tricks my friend George Reise, who is a forensic photographer, showed me. He has more advanced software to detect other discrepancies. 

[Test Screen Name]

Every professsionally produced photo you buy was probably opened and slightly improved or changed in Photoshop. It's normal. I think you might be using "photoshopped" to mean "faked". Or "Faked badly". Or something. But what is your specific concern - why do you want to know whether a photo was "photoshopped"?

[JJMack]

If the image file contains meta data Photoshop will store what version was used. Here I have opened an old jpeg image in Photoshop 2021 version 22.3.1. looking at the image's meta data you can see Photoshop  added a lot of meta data including the Jpeg was saved by Photoshop 7 in 2003.  If there is no Meta data was the meta data removed by Photoshop some image application removed the camera data. Photoshop is used by many.