Are the terms 'push' and 'pull' relevant/applicable to digital photography?

Question

The terms push and pull come from the days of film processing, and there's more on that here and here, but essentially they refer to increasing or decreasing the chemical processing time to account for intentional or unintentional under/over-exposure of the film roll.

When it comes to digital, we're no longer bathing films in chemicals, but are adjusting the exposure compensation knob on the camera, or an exposure slider in Lightroom/Aperture/Photoshop/etc. So I'm wondering if these terms are still relevant to digital photography, and exactly how they can/should be used—they certainly seem to be used by experienced photographers, so I want to make sure I'm understanding precisely what they mean.

First, which way is which? and is there a simple mnemonic or trick to remember?

Second, can these terms be used to refer just to intentionally over/under-exposing a photo (relative to the recommended metering) for artistic effect? Or do they always refer to a two-stage process of under/over-exposing in camera, then a corresponding & opposite adjustment in post-processing?

Answer 1

The terms push and pull are still relevant in the sense that they are still used and understood by many enthusiast photographers. But they are probably not as common as they once were. New terms, such as expose to the right describe the same concept using different words.

If you underexpose when taking the shot, then you push the exposure in editing to raise it. Conversely, if you overexpose when taking the shut, then you "pull" the exposure back down in post. Although there may be those who use push or pull when referring to intentionally over or underexposed photos that are not corrected at some point in the workflow in my experience they seem to always be used in the context of offsetting adjustments.

Answer 2

Along other expressions like unsharp mask etc. they are used in the digital environment in an analogus way to their classic usage.

Most common is "pushing" by correcting to the plus, preferrably while "developing" (another of these expressions) a jpeg or tiff out of a raw. Correction to the minus corresponds to "pulling".

Answer 3

I just thought about that the other day: using ISO adjustment to explore the tradeoff between sensor gain and other settings for indoor flash photography, I recalled that 1000 speed film was really just 800 with the developing "pushed". That was the only time I've thought about the term in digital photography workflow. It seems that anybody younger than my EOS 620 has no idea what those terms mean. It has not, like some other terms, been blessed with Photoshop icons paying homage to the original concept. I don't think anything is properly analogous, with the closest thing being "ISO extension", allowing the sensor gain to be turned higher than it is really meant for at the published level of quality.

Exposure compensation is not the same thing. Manipulating the exposure/highlights/darks/shadows/contrast in Lightroom or with Curves is a completely different thing.

Sure, you can brighten a picture that's underexposed because you were maxed out on your exposure settings, and that might be analogous enough for some; but I think it refers specifically to changing the sensitivity of the imaging media (film or semiconductor) as opposed to any manipulation of the data after exposure.

Pushing is not printing darker by increasing the exposure on the enlarger. It's getting a negative that has lighter areas by changing the details of the chemical reactions that fix the latent image. It makes the film more sensitive, beyond its stated range. That is, you are pushing the limits of the specification of the material. (does that help you remember it?)

Answer 4

If you thing in terms of N+1/N-1 which are ways of modifying a films contrast by over/under exposure and compensation during film development, then “curves” allows you to do the same but with much greater control.

If you think of the brightness histogram these techniques were used to pull in the highlights and shadows or to push them out. Use can use highlight/shadow/contrast/brightness to achieve this or use curves. The goal is to use the dynamic range of you film/sensor to it maximum. You expose to get you deepest shadows as close to the left and your highlights as close to the right in the histogram. You then adjust the desired tonality in post.