Truthful Photo Editing: Liquify and other Distortions

[This blog post is part of an ongoing series in which I discuss how best to apply Photoshop tools within a workflow in which strict adherence to the truth is critical, such as in photojournalism, forensics investigation, and scientific research.]

Don’t do it.

Seriously, the Photoshop Liquify command can be a useful creative tool, but I’m not aware of—nor can I imagine—any practical use of the tool that would maintain the truthfulness of an image. (Of course, I’m constantly amazed by the unexpected uses people find for some Photoshop tools, so feel free to let me know in the comments if I’m mistaken.)

In fact, there’s not much for me to say about the use of Liquify in a truthful editing workflow, but I have been thinking lately about just how big an impact this single feature has had on the “extreme” retouching we see all around us these days. When people think about the overuse of Photoshop, most typically it’s the results of the Liquify tool that come to mind.

In the event you’re not familiar with Liquify, it’s a Photoshop command that brings up a dedicated editing interface for pushing and pulling the pixels in any image just like putty. Here’s a demonstration video from Adobe’s own website that shows how the command works, but you might instead find it more amusing to watch this recent spoof video that features the command prominently.

What’s worth noting, however, is that this command wasn’t introduced to Photoshop until the year 2000 with the introduction of Adobe Photoshop 6.0, more than a decade after the first version of Photoshop first came to market. In retrospect, it’s now clear that this one feature of Photoshop has had a dramatic impact on the evolution of beauty and fashion photography. To get a sense of the impact, take a look at our Photo Tampering Gallery over the years. Prior to 2000, most of the controversies involving photo manipulation were not related to beauty and fashion, with the exception of a few examples of celebrity heads being pasted onto slimmer bodies. This begins to change in the new century, however. The first such example you’ll see in our gallery is the cover of GQ in September 2003, where Kate Winslet’s body has been digitally slimmed. The trend then continued to accelerate, and now of course there’s a beauty-related controversy in photo retouching almost weekly.

A marketing screenshot for the original Kai’s Power Goo.Similar capabilities actually existed in other software years before they were introduced to Photoshop. In fact, one of the more well-known applications with similar capabilities was a consumer product called Kai’s Power Goo, which was introduced in 1995 as nothing more than a fun tool for creating amusing faces. In fact, I was a Photoshop product manager at the time of the Photoshop 6.0 introduction, and I recall being concerned that the Liquify command too might be viewed as little more than a toy. Certainly there was a segment of customers who would find the tool useful for doing more surreal photo-illustration work, but at that time we were promoting Photoshop more heavily to mainstream photographers who were just beginning the transition to digital. Would they really find Liquify relevant to them? Then, our photography evangelist* came to me with a simple demo file that I thought worked brilliantly. It was a fashion shot of a model wearing a short skirt with leather boots. Though the model was fit, the boots were a bit too tight around her calves, and this caused a distracting bulge of flesh along the top edge of the boot. A single swipe with the Liquify tool pushed this bulge back in and removed the distraction. 

The original, and relatively subtle, demo image for the introduction of the Liquify command in Photoshop 6.0 [photo credit: Tim Mantoani]

This seemed like a useful and reasonable application of Liquify within a pro photography workflow, but still I was concerned that it might seem unorthodox to be applying distortion to a model shot. I demonstrated the feature dozens of times on press tour and in our trade show booth after the announcement, and I was always careful to explain that, despite Liquify’s ability to easily twist an image in extreme ways, it was the subtle application of small amounts of distortion that would be most useful to pro photographers looking to clean up their images. During the demonstrations, I even did my best to maintain a slight bulge above the boot, lest anyone think I was pushing things too far.

Clearly, I needn’t have worried about being so subtle! Liquify was embraced by fashion retouchers to an extent I never would have dreamed, and at times to an extent that I would have been embarrassed to display within my own demonstrations. Of course, it’s not everyone who uses the tool to such an extreme extent. There are many retouchers who use it reasonably and in moderation. 

Liquify is not an “evil” command. As with all of Photoshop’s editing tools, it’s the context that should determine what tools are appropriate to apply, and in what way. If you’re creating a surreal photo composition, then by all means go to town with Liquify. If you’re doing some retouching for a fashion spread**, then some minor tweaks here and there are acceptable. But, if you’re pursuing a strictly truthful photo workflow, Liquify is one command that shouldn’t be in your arsenal.

* - I would name the photography evangelist, but I’d hate for her to think I’m blaming her for the overuse of Liquify in the media. She’d be horrified.

**- Of course, there are always exceptions. Some fashion spreads may be more about artistic vision than about a realistic portrayal of the model and the clothing. For a great example of this even before the days of Photoshop, check out this article on the Jean-Paul Goude exhibit, currently on display in Paris.

Comments

[Richard Hanes]

I hate photoshop and other similar tools. Now they make online dates impossible because they retouch the photos in such a way that they all look like Pamelas and Jolies. Seriously, they should ban photoshopped photos in social networks!

Richard C. Hanes

[Jim]

How truthful should we consider other distortions such as skew, perspective, and distort (in Photoshop's transform settings)? And do you see the vanishing point filter as fair game?

I noticed a neat post of yours later on in this blog demonstrating a forensics technique in which vanishing point is used to obtain the number from an otherwise unreadable license plate. I've always tread carefully around such subjects (as a Photoshop instructor, I get asked for advice from the local police a few times a year) because I am aware of some of the artifacts and alterations that can result from transforming an image. I avoid, for example, using over-aggressive scaling of images, for the fear that an enlargement may suddenly appear to provide a clearer photo of a suspect while it in fact might only be causing the appearance of features (tattoo, facial or neck hair, etc) due to stretching or duplicating pixels.

So, while I typically look at transformative distortions in the "don't do it" category, there's also the potential to pull some impressive details out of a photo with these tools...provided that appearances don't ultimately deceive. Do you have any guidelines, methods, or tools that would suggest the cutoff along these lines? For example, is there a certain amount of distortion after which we *couldn't* be certain of the validity of a plate number in spite of its appearance seeming decently clear?

And then, by extension, to these other transforms (even liquify), is there an amount of pushing pixels around that is quantitatively too much pushing? The extreme cases always seem clear, but the forensic cases elude me :)

Thanks for any insight!
-Jim

[Great questions. As a general rule, any tool or command that distorts the image is something to avoid, but--as evidenced by my Vanishing Point example--there are usually exceptions. Generally speaking, distortions that follow a predictable, geometric formula are more likely to have some reasonable applications, particularly when it comes to compensating for the opposite distortion that may have been introduced by a camera lens or a bad vantage point. In fact, lens corrections that are based on profiles of the actual lens used to capture the image are among the safest "distortions" to apply, because they leave much less room for human error. As for whether you can trust the pixels in an image to which distortion has been applied, I think you have to factor in the possibility that the stretching of pixels introduces some uncertainty. For example, in the case of a license plate, it would be wise to examine the resulting letter forms and consider every possible letter that might have resulted in that configuration of pixels. In certain cases, this might mean concluding that there are several possible license plates instead of just one. As always, nothing substitutes for good judgment. - Kevin]