Performing Unnatural Acts in Photoshop
Although it has been supplanted by Lightroom for many users, Adobe Photoshop was long considered the standard for optimizing and editing digital photographs. Photoshop has a long history and a long legacy. But Photoshop was never designed with a streamlined workflow in mind. In fact you have to really work at it to correctly use Photoshop. You basically have to be willing to perform unnatural acts in Photoshop to avoid damaging your images.
Those wanting to make an adjustment to an image would naturally be tempted to make use of the list of Adjustments under the Image menu. After all, why else would Adobe have called it that? But if you fall for this, you will be making changes directly to the pixel data of your image, causing degradation from rounding to every red, green and blue value you worked so hard to capture in your camera. Everywhere you look this menu is filled with this trap. Back when Photoshop first came out, there was no such thing as "layers" let alone "adjustment layers" or "non-destructive editing techniques" so Adobe placed the tools that did exist up front and center. Most of them are still right there, with newer, better options scattered elsewhere if you want them, not nearly so obvious as the originals.
One of the worst offenders was right at the top of the list. "Brightness/Contrast" may seem like a reasonably normal adjustment to make to an image, but the option of that name atop the Image Adjustment menu is a bad way to achieve this goal. In its original incarnation, it would not only cause damage due to rounding and truncation to every pixel it touched but would also allow you to push the brighter areas of your image right off the top of the scale resulting in burned out highlights without a peep of warning that this was happening. Some years back, Adobe attempted to remedy this in Photoshop CS3 by tweaking the underlying algorithms employed. But to avoid the chance of upsetting anyone who actually like the way the tool had been working, they kindly provided a checkbox to "Use Legacy" algorithms. No photographer in their right mind would want the legacy behavior, but perhaps someone out there did, for some other purpose. Photoshop is for much more than just photography.
Problems of this sort begin even before you open an image to begin working on it. A standard installation of Photoshop will leave the unwary user editing their images in 8-bits per pixel using the sRGB color space, two variables that are poorly suited to getting the best results. Perhaps when computers didn't have much memory and drive space was precious there may have been good reason to be prudent with file sizes but not anymore. And while sRGB may have been intended as a default color space for the web, it has far too limited a gamut for working with images intended for printing. Yet only those users knowledgeable enough to understand the issues or at least heed the advice of those who do will be likely to be working in 16-bit mode with Adobe RGB or better still ProPhoto RGB.
There's just no getting around it. You have to avoid all the obvious image editing tools in Photoshop to correctly employ it as a modern means of serious optimization of photographs. Effectively using Photoshop requires that an amazing number of foundational concepts be understood — concepts that seem to bear little relationship to working with photographs. I mean, do photographers really need to care about the difference between "assigning a (color management) profile" and "converting to a profile?"
Photographers once had to scan their slide film to work on images digitally at all. Once digital cameras exploded onto the scene, users could open their images directly without scanning but the same baggage from Photoshop's long history still awaited them once they did so. Adobe addressed the proliferation of raw image file formats by introducing Camera Raw as a Photoshop plug-in to allow users to open new breeds of file formats as camera manufactures introduced them. Yes, you could more freely make changes to tone and contrast through Camera Raw without worrying about image damage, but you left all those non-destructive benefits behind once those raw images were open in Photoshop proper. And unless you knew better, you were likely opening them in 8-bit sRGB mode.
Granted, I've written extensively about many of these topics over the years here at Earthbound Light. They still have their place just as Photoshop still has its place. Not everything a photographer needs to do can yet be done in Adobe Lightroom, but it's getting less and less often that I find a need for Photoshop. Most images can be optimized just fine in Lightroom where everything I do remains part of an integrated workflow.
And let's consider for a moment what one needs to know to stay out of trouble in Lightroom versus the many traps that exist in Photoshop. Yes, Lightroom is built on a database, something that is a true strength but one that does take a bit for some beginners to get used to. The idea that your Lightroom catalog merely points to your image files rather than actually containing them isn't obvious to some new users. And if you move your images around outside of the program you will surely confuse Lightroom when you next go to work on them inside the program.
But most everything else is actually relatively intuitive and defaults to keeping you and your photographs safe, while Photoshop defaults to modes that actually damage images. Lightroom is workflow based while Photoshop is image-centric. Lightroom at least tries to guide you through what one normally needs to do while Photoshop is just ... there — a haphazard collection of tools with more than a few hidden surprises awaiting the unwary or the unknowledgeable.
I still like Photoshop but have yet to come up with a good reason for upgrading from CS5 to CS6. But I find I like Lightroom more these days. I recently helped teach a photography course that included a day on digital editing. We hold the same class each spring. Since Lightroom was introduced, we've tried to cover both it and Photoshop equally to avoid playing favorites. It's just that it's getting harder and harder to justify teaching Photoshop. Serious photographers should use Lightroom and only truly advanced users still need Photoshop, and as I say, only occasionally. There's just no need to continue performing unnatural acts in Photoshop when better alternatives exist nowadays.