Screen brightness vs contrast perception

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I went on a vacation this year with a photographer friend. When we looked at our photos, his looked garishly over-saturated and overly contrasty to me, and mine were flat and dull to him.

This puzzled us both, and we investigated. As it turned out, the culprit was that I work and edit in bright surroundings, while he works and edits in a dark room. Alas, contrast perception depends on brightness; at twilight, all flowers look dull. So it all makes sense, but it’s unsatisfying nonetheless.

The sRGB and Display-P3 standard for desktop colors define a dim screen in a dark room for editing: screen brightness of 80 nits, with 20% surround brightness of 16 lx. Adobe’s aRGB goes a bit brighter with 160 nits and 20%. The HD video standards BT.1668 and Rec709 go darker with only a 1% surround. Digital cinema standards like DCI-P3 are mastered in complete 0% darkness.

However, the standards for office lighting recommend at least 300 lx of ambient lighting, and up to 1000 lx if good visual acuity is required. That’s >10x the sRGB surround brightness. In this sort of light, a sRGB 100 nit screen is unusably dark. In my well-lit office, I need to turn up my screen to at least 250 nits to get a reasonable brightness. Most consumption nowadays probably happens on mobile devices that are typically in bright surrounds. Prints are also typically viewed in good light.

The problem is, surround brightness messes with perception. If you edit your photos in my bright room, you’ll end up with a lot less contrast and saturation than in my friend’s dark room.The photos will look the same on our screens, but due to the different surrounds, they will encode very differently.

I have since tried to edit with a bit more saturation and contrast in general, and also turned down my screen brightness a little.

But it still seems like an unsolvable conundrum. The editing standards sRGB/aRGB/Display-P3 are just plainly at odds with office lighting standards or typical viewing environments. There’s just no “right” way to do things unless you know how the photo is going to be presented.

In what sort of environment are you editing?

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I don’t really have that much control over my surroundings but I usually never take any steps to change it when editing.

What I do is make sure that in darktable the white frame is always enabled, and then go from there. I believe this is a game changer and a must have for evaluating proper brightness in any environment as it gives you a pure white 100℅ brightness reference point both against the image and the middle grey background. Then after exporting I also check out my pics in my phone and then with the lights out and blinds shut, but it usually doesn’t make much difference.

I believe the frame is really key, along with zooming out on your picture. Aurelien had a good article about this here on pixls.us.

I have seen a few of your edits here on the forum and they look fine. Are you sure this isn’t due to taste differences as well?

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I have found out that editing in a room where the table is lit just by an LED strip (about 7W, max. 12W) gets me the best results. If I edit during daytime, I get very flat blacks and end up needing to re-adjust my edits.

I have no idea what the lx values are, but I find it that the easiest to get what I want is to edit at nighttime. Those images then look good in the day as well.

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I work in a room with a single led bulb (possibly about 14 W?) It is a bright enough room for comfort. But I do find the white border around the image helps with assessment. I also find that I often edit an image for playraw on this forum and when I see the posted result it is darker and duller than I expected. That may be partly due to the display background of white on this forum compared to grey in darktable.

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Over the time I’ve fiddled a little with calibration and setting up a somehow “proper” working place at home. At least I try to get some understanding about all this - allowing me to have a kind of feeling what I need to consider when editing under different environmental light conditions.

Key for me is using the standard gray darktable theme, and having the white color assessment frame activated all the time as @hatsnp also wrote. I think the latter is the most important, as to me it ensures that the eyes somehow anchor very well.

Additionally I set up color calibration of my screen for three different environment light levels: 90 / 120 / 160 lx with a 6500K target. For print I target at 5000K.

When having the goal of somehow reproducible results (whatever this may mean :wink: ) I mostly try to edit at the same ambient conditions, e.g. at night with the display at 90lx or perhaps 120lx and a dim ambient light from an LED lamp set at 6500K.

Additional helpers: my display has a black matte DIY shading hood that helps to reduce eye distractions and lets me work comfortable also over a longer period. I’m also using an Android app called “LuxMaster” as a kind of helper to get a rough thumb-estimate about my surrounding light intensity. And I really try to avoid editing under very light environmental conditions (mainly to avoid the contrast effects you described @bastibe…) Therefore I haven’t set up a calibration profile above 160lx :grin:

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I’m sure that’s part of it. But it’s also more than that. Another aspect was that this vacation coincided with me getting a new computer monitor, which I wasn’t quite accustomed to yet.

In particular, the new screen has far better anti-glare coating, which makes blacks look much blacker. This wouldn’t matter in a dark room, but in my well lit office it makes a surprisingly large difference.

The color assessment mode certainly helps. As does the grey color scheme (although I find the middle grey one too ugly, and usually choose the darker one instead).

That’s very interesting to hear, so I’m at least not alone with my struggles. My thinking was that I can’t properly darken my room during the day, but can easily light it at night. So if I’m going to standardize, it would have to be for the bright side.

But reading all this, I might need to actually lower my room brightness a bit for editing. This is a bit annoying, as I’ve spent quite some effort to get it nice and bright for work, which I find is much better for my general wellbeing.

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I’ve never thought too much about a “bright” environment to be honest…

Some of my understanding derives from Alexis van Hurkman’s “Color Correction Handbook” (a book, I recently recommended in another thread - it’s really worth reading).

I’ve just read through some of the related chapters while answering here and there seem to be two main set-ups:

  • display at 80-120cd/m² with a ambient light of 1-10% display white
  • display at 200-320cd/m² with 20% ambient light level (which also isn’t really bright at all)

So for my desk, I followed more or less the first recommendation. Well, I may give the second also a try :thinking: Grading the same photo under both conditions and simply compare…

He also recommends to have a mostly neutral surface surrounding the view area - something one may also pay attention to :crazy_face: e.g. painted at 18% gray to avoid color casts. Something I definitely haven’t covered yet in my set-up :grin:

And one should make sure that the surrounding light doesn’t illuminate the wall behind the display evenly, but produces some gradient (no matter if it gets darker from top to bottom or the other way round). This gives the eye some variety to counteract eye fatigue.

Quite interesting stuff :sunglasses:

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