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See this screenshot: Histogram

The not-yet-processed image depicts a rural landscape right after sunset. It looks like this: enter image description here

Its parameteres are: Canon EOS 70D + EF 24–105 mm f/4 L IS; ISO 800; 1/13"; f/6.3; +1/3 EV; 47 mm.

UPDATE: Here is the original image together with the histogram in darktable: Histogram in darktable before adjustment, and here is the image after white / gray / black point adjustment: Histogram in darktable after adjustment

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    \$\begingroup\$ What is your notion of what it means to "resolve a ... histogram"? \$\endgroup\$
    – twalberg
    Nov 13, 2019 at 20:36
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    \$\begingroup\$ I meant to adjust the brightness curve with maximum contrast without enhancing noise too much. \$\endgroup\$
    – Neppomuk
    Nov 13, 2019 at 20:58
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    \$\begingroup\$ can you post an image you want to replicate? or "i want look like that, here is my starting material" \$\endgroup\$
    – aaaaa says reinstate Monica
    Nov 14, 2019 at 0:05
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    \$\begingroup\$ The histogram matches the image. It's what I would expect the histogram to look like. What bothers you about the histogram? \$\endgroup\$
    – doug
    Nov 14, 2019 at 2:43
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    \$\begingroup\$ Why do you think this specific shape needs any special treatment? \$\endgroup\$
    – ths
    Nov 14, 2019 at 13:26

2 Answers 2

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You want to get trim the flat or empty ends of the histogram or levels. There are many great videos and tutorials on it.

Here's fixing the levels in photoshop on your photo from your post. You drag the pointers in to where there's more info than a flat line. You'll also need to restore saturation and contrast. I didn't do that to the example:

enter image description here

enter image description here

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  • \$\begingroup\$ Save for me not using Photoshop, this was the solution (see my updated question). Thank you! \$\endgroup\$
    – Neppomuk
    Nov 15, 2019 at 20:30
  • \$\begingroup\$ Is it just me or is there a halo around the trees? \$\endgroup\$
    – OnBreak.
    Nov 18, 2019 at 21:32
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There are quite a few different ways to stretch the contrast of a low dynamic range image, all with slightly different tradeoffs in the actual effects (and side effects). One of the most common is what Photoshop calls "levels" - you essentially choose what levels in the histogram you want to call black, white, and a mid-gray. Here's a decent tutorial, based on Photoshop's version of that tool. Depending on what toolset you are using, other adjustments would be the brightness/saturation/contrast group, gamma correction or curves, or something like Ansel Adams' zone system (which darktable implements quite nicely).

No matter which method you use, you have to be careful to avoid unwanted side effects, like posterization/banding, unnatural color changes, enhancing noise too much, or making the image look artificial. You'll have to play with the relevant parameters to see what is acceptable to you.

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  • \$\begingroup\$ I'm using Darktable and Gimp. \$\endgroup\$
    – Neppomuk
    Nov 13, 2019 at 21:17
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    \$\begingroup\$ In that case, personally, I would start with the Exposure module - set the exposure to somewhere between +2 and +3, it looks like to me - just enough so the histogram touches the right edge - and then drag the black point to the right until the histogram starts to touch the left edge as well. Once I was satisfied with that, I would play with the Zone System module to redistribute various luminance bands a bit. \$\endgroup\$
    – twalberg
    Nov 13, 2019 at 21:28

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