You cannot believe everything you read ̵
Airbrushing is easy to spot
Have you ever seen an image that just doesn’t look right? Trusting your gut may not be the most scientific approach, but you are probably better at detecting counterfeits than you think. If you see an image that rings alarm bells, you may want to take a closer look. You will likely see some telltale signs that it has been manipulated.
Airbrushed images often fall within the “creepy valley” territory. Even if you have perfect skin, most light sources cast small shadows on fine wrinkles, pores, and other small imperfections. When these imperfections are removed digitally, so is the appearance of natural lighting.
Professional retouchers often strike a balance between perfection and realism, but amateurs and mobile apps rarely do. Apps in particular depend on existing skin tones to determine which parts of a frame to retouch. This often results in a heavy-handed airbrush effect that is easy to spot.
Check for signs of warping
Sometimes you have to look beyond the subject of a photo to see the full picture. This is especially true when it comes to warping, that is, when someone uses a tool to grab a part of an image and move it, reduce it, or enlarge it.
Look for straight lines in the background and see if they comply with the laws of physics. For example, if someone shares an image of their bulging biceps, and a row of tiles in the background is unnaturally distorted near those biceps, that photo has been edited to accentuate muscle growth.
This same technique is often used to exaggerate weight loss or the effects of “slimming” clothing.
Look for patterns and repeated objects
Cloning is a basic Photoshop technique where part of an image is duplicated. It is often used to remove small imperfections from the skin by “cloning” another part instead. This also eliminates telltale signs of airbrushing.
This technique is also used in other ways. The object being duplicated can be part of a crowd, a tree, or even stars in the night sky. It’s an effective way to make a landscape photo stand out by popping in a few more colorful flowers. You can also make a football stadium or event look a lot busier than it actually is.
The giveaways in this case are recognizable patterns that appear in the picture. Look for unique aspects in a striking detail and see if you can see that detail in other parts of the image. It could be someone wearing a unique hat in a crowd, a certain pattern of stars (or constellation), or a tree with the same lighting that appears elsewhere in the picture.
Don’t forget the shadows
This only applies to the very worst of image manipulations, but don’t forget to look for a shadow. It’s a beginner’s mistake, but a human still makes. Sometimes an object in an image doesn’t cast a shadow at all.
All objects in a scene must cast a shadow. And if you take a group photo at 5pm, you expect the setting sun to cast a longer shadow than a photo taken in the afternoon. This can be more difficult to spot in artificially lit scenes. However, if you see the sun, make sure that the length and angle of the shadows match.
Also see how shadows are cast on each subject. If you have a textured object, such as a rock, the shadows should look very much like other textured objects in the image.
Look for out of focus areas and JPEG noise
When an image has gone through the cycle of being shared, saved, and re-uploaded to social media a few times, you often see compression artifacts. You may see some unsightly blurry areas and colored edges on hard edges. When an image has been updated, similar unsightly artifacts often appear right around the edge of the edit.
This is even easier to spot in combination with unusually smooth or solid parts. For example, you can see this if someone has tried to remove text from a white object by painting over it with a white brush. JPEG artifacts often stick to the edge of a painted area like glue.
Any unusually smooth areas of unnaturally solid colors should ring alarm bells, even with high-quality JPEG files.
Check EXIF and geolocation data
EXIF data is metadata that is stored with a photo when it is taken. This includes information such as which camera was used, the focal length, aperture, shutter speed, ISO, and so on. Location data in the form of real-world coordinates is also often stored in a photo.
To understand EXIF data, you need to know a little more about photography. If the image you are looking at was shot with a very shallow depth of field (such as f / 1.8), you would expect a very blurry background. A slow shutter speed means that moving objects become blurred. A long focal length (such as 300mm) should compress the background and create a “flatter” image with a reduced depth of field.
If these parameters (and others) do not match the image you are seeing, it is possible that the image has been manipulated. Likewise, EXIF data can contradict a story. Suppose two images were taken close to each other to display a longer period. If you are lucky enough to have access to the geolocation data, jump on Google Maps and view the location with Street View or satellite imagery.
Keep in mind that any editing tools used on a photo, including Photoshop or GIMP, are also listed under EXIF data. However, this does not necessarily mean that an image has been manipulated to deceive. There are many legitimate reasons why photographers use photo editing tools, such as minor adjustments or batch edits.
Use “Image edited?” decide
In addition to zooming in and pixel-peeping to spot clear signs of image editing, there are also tools that can help you spot fake ones. The most basic of these is a website called Image Edited? that assesses whether an image has been retouched.
Image edited? uses most of the techniques discussed above to check and report if any inconsistencies were found. The tool examines EXIF data for inconsistencies in areas such as camera models and color spaces. It also looks for JPEG artifacts, oversaturation, patterns suggesting that parts of an image have been cloned, and mismatched images in directed light.
We tested a clearly manipulated image and Image Edited? reported that the image was “probably” manipulated because “pixels only match software editors”.
Take a deeper look with FotoForensics
FotoForensics is similar to Image Edited ?, except it leaves the analysis to you. Rather than making a decision for you, the website produces an error level analysis (ELA) visualization. This can potentially emphasize Photoshopped features that you may not be able to see with the naked eye.
According to the ELA tutorial, you should “look around the image and identify the different high contrast edges, low contrast edges, surfaces and textures. Compare those areas with the ELA results. If there are significant differences, suspicious areas are identified that may have been digitally altered. “
The best way to get the most out of FotoForensics is to sift through the examples given to learn exactly what to look for. We tried this one with a manipulated photo of a crashed truck with good results. The edited parts of the image contrasted clearly with the rest of the image (see above).
Use reverse image search and fact-checking websites
If all else fails, why not look for it? Google Image Search allows you to do a reverse image search to find other copies of the same image online, as well as images that look the same. This should help you find websites that clearly state that the image is fake, or you may even find the original, unedited version.
You can also search for information about a questionable image on fact-checking websites. For example, let’s say there is an image that claims to show little green aliens on the streets of New York City. You could search for “little green aliens New York” to find analysis of the photo, and you would likely find fact-check articles explaining that those little green aliens aren’t real.
That’s an extreme example, but the same technique applies to other suspicious or controversial images floating around the Internet. Do a quick search and some research before you believe what someone claims to be showing.
Seeing is not always believing
Photoshopped images are nothing new. They have been around since the birth of the Internet and are re-sharing them. Many people have been victims of it in the past. And as increasingly sophisticated techniques become more accessible, many will fall for them again in the future.
However, now you know what to look for so that you can better analyze an image for signs of tampering.
If you also want to learn how to spot video fakes (or “deepfakes”), read this article!
RELATED: What is a deepfake and should I be concerned?