Working "Highlight Priority" Autoexposure Compensation

Highlight Priority settings don’t seem to work properly.
80% of my images when set to “highlight priority (slight)” end up with 0.00 exposure compensation or -0.50 exposure compensation.

This doesn’t make sense. The highlights have varying levels based on exposure, and a severely underexposed image never seems to have a + exposure compensation as it should.

Note “center weighted” works okay in that each image gets a compensation value calculated to 0.01 resolution.

Highlight priority just doesn’t produce any reasonable adjustment based on the image.

Click on the ? mark next to “Exposure Compensation” to see a description of what Highlight Priority does. What I see is that it doesn’t lift highlights when exposure is low. It is used to help recover clipped highlights. If your images aren’t greatly overexposed, Slight isn’t going to do anything - whereas Strong seems to be especially aggressive by lowering overall exposure while keeping highlight levels high.

For what you want to do, Smart Lighting might be the best adjustment to use.

This is just exposure compensation after all. This is calculation of an overall exposure compensation value based on the highlights. You can tell that because if you set manual exposure comp and pick the same number selected with “highlight priority” (usually 0 or -0.5) you get exactly the same image…

There is no special treatment for highlights (that’s what selective tone is for.)

My fundamental problem is that If I took a 9 exposure bracket at 0.3EV per step, and assuming no overexposure, I would expect 9 different Exposure compensation values using “center weighted average”, and I would also expect 9 different exposure compensation values (assuming no substantial clipping on the highest exposure images in the bracket of 9 images), but that’s not at all what you get.

I want a few options for auto exposure adjustment. And the only one that works as expected is center weighted average. The others basically don’t work in any predictable way.

Hi Mike,
tried it (the first time eversince) with different raw-files, that is from different people / cameras.

And yes, it did as promised, correcting the exposure level

  • in relation to the individual highlight level of the different pics (Highlight Priority)
  • in relation to the individual lightness of the different pics (Center Weigthed Average)

Well, it looks like these functions are for ease of use, giving a proposal for the overall exposure.
– If I understood your test, there was no substantial overexposure (because you exposed properly) and with that those three “Highlight settings” don’t give you a ‘regular’ correction.

Maybe it’s a problem with Sony raw files only.

But if you used this on 50 files what’s the distribution of exposure adjustment? Do you get a continuous distribution? Or do you get discrete values?

I don’t have any problem with Highlight Priority, at least, on the type of images it was designed for.

Centre-Weighted Average…

Capture d’écran 2021-11-09 à 14.17.58

Highlight Priority - Slight…

Capture d’écran 2021-11-09 à 14.18.04

Highlight Priority - Medium…

Capture d’écran 2021-11-09 à 14.18.10

Highlight Priority - Strong…

Capture d’écran 2021-11-09 à 14.18.16

Or, by ignoring Exposure Compensation and using Spot Weighted Smart Lighting, I can get a perfectly balanced exposure by placing zones over the highlights and shadow regions…

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I don’t know if I understood you, but exposure adjustment is a global adjustment. It’s something else as the selective tone tool.
Editing should always be done on individual images.


It’s odd to me that the exposure compensation is always such discrete values. Even the example given above the exposure comp is -0.5 and -0.99.

Almost always 0.5 +/- 0.02 or -1.0 +- 0.02. Or zero.

Try to find an example where highlight priority decides exposure compensation between -0.6 to 0.9. Or -0.1 to -0.4. Occasionally you may find one. But almost always the resolution correction is 0. -0.5, or -1.0. It makes no sense.

It also doesn’t make sense that for a grossly underexposed image that highlight priority can’t bring the highlights up with a positive EC but that’s another story.

My guess is you guys don’t use this feature much.

As I said before: editing has to be done on individual images.There doesn’t exist something as a good EV correction for 1000 images by example. Exposure compensation is global. Find yourself a right number in 1 image and copy that to the other 999. You won’t be happy with the result.
I never used the possibilities you mention. And I don’t see why I ever would.


trying to explore … :slight_smile:

While the manual ‘talks’ about the three different levels of Highligh Priority Automatic mode
(and refers to verify the results in the histogram in any case ! ), the ?-help points out
“Highlight Priority [ … is ] Recommended when trying to recover clipped highlights”.

→ PL’s Highlight Priority modes can only reduce the exposure.

correcting different pics all at once … :slight_smile:

To find out, I chose two very different pics

  • (A) - a shot right in a bulb → dark, except bulb close to full exposure
  • (B) - a sunset shot with striking sun → backlight landscape, partly overexposed

and examined with

  • Highlight Priority - Slight

    • (A) - 0,17 exp.comp.
    • (B) - 0,50 exp.comp.
  • Center Weighted Average

    • (A) + 0,66 exp.comp.
    • (B) + 0,36 exp.comp.
  • Smart Lighting Auto (= uniform, slight, 25)

    • (A) a little brighter than HP-S
    • (B) a lot brighter than HP-S
    • (A) a lot darker than CWA
    • (B) a lot darker than CWA

→ Based on those randomly chosen pics the application of “Hightlight Priority - Slight”
and “Center Weighted Average” resulted in different exposure compensation values.

→ “Smart Lighting Auto” obviously changed the overall brightness
(also didn’t evaluate the impact on the pics’ dynamic range).

For sure, one can apply those ‘Auto modes’ on a selection of pics, but as @George said
editing has to be done on individual images.

I’m not questioning editing has to be done on individual pictures but I often have galleries of 200-400 images that I want to edit as quickly as possible. So I want as close as possible a starting point for all images and then manage by exception. Flip through each image. Adjust horizon and crop, and adjust exposure if necessary. I’m trying to bring the editing process for 300 images down from 3 hours to 2 hours and then to 1 hour.

For others who go out and capture 50-100 images and choose 3-10 to edit this is not important. But I shoot 1000-1500 images and have a very quick process for downselecting to the 300 I want to deliver… (this is outside DXO). Now I want to edit and deliver those 300 pics as quickly as possible.

Well yes, I understood already what you are trying to achieve. :slight_smile:

Suppose, Center Weighted Average (maybe as preset ?) will be your first choice, especially as your pics shouldn’t be so far off like my test examples. And if necessary your selection is quickly refined with Smart Lighting Spot weighted …

Yes center weighted average works great for some jobs. But other jobs mostly at night with sometimes harsh lighting and center weighted average does a very poor job (not center weighted average’s fault). So I thought highlight priority would be better, but it simply doesn’t work consistently enough. Two different but very similar and similarly exposed images and one will have a 0.0 correction and the other will have a -0.50 correction. When the exposure difference is off by less than 0.1…

Anyway I thought I would try to suggest this feature can be improved but apparently no one uses it. :joy: