Process Specifically, Not Generally

First in a series of Post Processing 2022 articles.

For some time now—years—I've been teaching a different approach to post processing images to the one that most of you are using. Adobe's latest addition of masking tools should definitely make you stop using the approach you're using and switch to mine, but...

Wait, what am I babbling about today? 

What I teach in raw conversion is essentially a simple notion: the difference between treating an image generally, or treating parts of an image specifically. 

The tried and true method of processing an image using an Adobe converter (Lightroom, Photoshop) is basically this: 

  1. Open the image (Lightroom Develop module, Photoshop ACR).
  2. Adjust the exposure (e.g. Exposure, Highlight, Shadow sliders).
  3. Set sharpening and other parameters.
  4. Done.

Not so fast there, buddy. I'm pretty sure you're abusing your image data in Step 2.  In so doing, you're creating a sub-optimal result. And you probably don't want to do #3 across background out-of-focus areas. Ever wonder why you want to apply a Gaussian Blur to the background you just sharpened? ;~)

Right. Don't apply global changes, apply specific changes to specific problems using masking. Before Adobe added the masking tools to Lightroom and ACR, I used layers to do what I'm about to suggest. Those of you with long memories may remember folk like Vincent Versace showing off their processing with dozens of layers. Well, specific processing as opposed to general processing is why they were doing that. The nice thing about masking is that it is non-destructive, so you can change your mind later (Photoshop users need to consider using Smart Objects).

For example, the following two images show the way I see most people processing their image (the generalized approach). First, here's what an image looks like brought into ACR:

This image looks dull and underexposed, so a few common sliders are mushed aggressively:

First you slide to the left (highlights); then you push it to the right (shadows); put your hands on other sliders, add image-wide sharpening and we're done for the night. [Okay, not exactly Rocky Horror Picture Show re-write, but you get the idea.] This is the right way to do things (generic targeting), yes? 

Nope. Here's my quick and dirty processing using my version of post processing conversion logic (specific targeting):

Only one slider seems to have been moved! That's correct, because I only changed one thing generically on the entire image (lifting the shadows across all areas). Everything else was done specifically. That means I changed the sky with masking, I changed the giraffe with masking, I changed the giraffe's eyes with masking. I dealt with specific problems in the image with specific tools (which don't show up here because I'm not showing you the individual masking steps).

We haven't even gotten to some of the other things I use in ACR (Color Mixer, Color Grading, Detail, etc.). All I've dealt with so far are some basic tonal adjustments. Yet you should see that my example is better. It has more contrast, more color, delineates the giraffe better, and more. (No, I'm not arguing that this is a particularly good image. I actually chose a blah image to work on because it illustrates my point more easily.)

What I'm suggested here is no different than we used to do in the darkroom. Often we'd print a "base" exposure, let it dry so we could see what was happening in tonalities clearly, then mark it up with a Sharpie to suggest which areas needed less (dodge) and which areas needed more (burn) exposure. In our subsequent prints with burning and dodging we were dealing with specific areas, not the overall general print.

So why don't you want to do a generic (all pixels controlled the same) conversion, then later use Lightroom or Photoshop tools to adjust specific things? Because you're locking in pixel values that are sometimes more difficult to change, or will show the evidence of such changes when you make them (e.g. increased noise in an area). 

Note the sky in my specific-processing (third) example: you'll have a tougher time later getting that blue if you demosaic everything as in the generic (second) example, because you locked in that muddy cyan color in the pixels. Now when you try to change that after the generic processing, you'll have problems with the sky behind the out-of-focus branches on the right: it'll become obvious you're changing sky values.

So first lesson in post processing: make your conversions specific to observed problems, not generically across the entire image.

Also posted in Technique/Post Processing 2022. Please link to that version.

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