PL Smart Lighting has lost algorithm to process (purposefully) under-exposed images from ISO-Invariant sensors

I think there are scenarios, where changing certain local adjustments, has effects on some global adjustments.

I know for example for sure, that the local white balance influences the global clear view. Maybe the old global lighting modes were also local white balance dependent and showed even more instability compared to global clear view.

PhotoLab needs process versioning very soon. Otherwise the implementation of new innovative stuff will be blocked, only because legacy algorithms exist, which still have to work somehow or have to be dropped, like in the given case.


Although I don’t really understand what you want to express (do you ask why or whether local tools influence other parts), I can confirm that local corrections currently do influence other parts of the image and I consider this pretty bad. I filed a support request some time ago which has been closed meanwhile with a comment that the developers work on a solution.


I am not completely grasp the smart-lighting system, but as far as i understand it searches dark(near black and shadow) and bright/blownspots and it tries to get both in to a more narrow Dynamic Range. (lifting the black/shadow) and lower the bright/blown as in a tone curve tool, rearranging the tonal curve, more flat and intelligent algoritme is preventing the contrast from getting “dull” by shifting contrast centre, gamma, blackpoint, whitepoint and using micro contrast to keep detailing crisp. this is a s-curved line like the tone curve without the pin points you can add to get more edged corners in the line. If you got a controlpoint someware in that curved line and start shifting exposure/contrast/color saturation it should be behaving as a pin point in that s-curved line and this can be effecting in strange corners in that line. But because it is local what does this in other parts of the image which have the same “luminance” value in that curved line as where you pointed the controlpoint?

And if smart-lighting is a continues adjusting tool reacting upon your corrections in other tools like micro contrast/ colorsaturation it changes its settings along the way you edit.
(because i use the smart-lighting with the “face” boxes as first stage exposure-correction by lifting shadows and lowering bright /blown area’s and boxing the faces of interest, would it be good to know if this first step is ones set/chosen saved and all other corrections are build on that or not.
Because from there i adjust contrast levels, selective tone levels, vibrance, and also use local correction.

Maybe i need to use a controlpoint and or gradient filter first and over that activate my smart-lighting. settings.
(That is why i would be thrilled if all tone curve influence tools are visualised in the histogram combined with a actual tone curve which represet the actual resulting tone curve if sliders are changed. This way you can see the actual influence on the image not only on the preview but also on the reaction of the tone curve.)

Better then this can’t explain.

ISO invariant images.

My only ISO invariant images are coming from an A6300 (mainly a Canon shooter) so I don’t have a huge stake in this race. Surely just making the Exposure Compensation play well with ISO invariant images and Smart Lighting would be the trick. I.e. first step would be to apply Exposure Compensation to bring image up to the approximate desired tone curve and then apply Smart Lighting to the result. Smart Lighting would then pull back the blown out highlights and push up the shadows. It’s asking a lot of Smart Lighting to guess intention without a starting point for the basic correction.

An additional Exposure Compensation slider could be added to Smart Lighting (EL correction) but that’s more duplication of controls. Some kind of AI could be added to Smart Lighting - when Photo Lab knows that a sensor is ISO invariant (and yes it has to know) and the correct ISO has been chosen for ISO invariance (usually ISO 800 but it varies), Smart Lighting could throw a dialogue: “I’ve detected an ISO invariant exposure here. I recommend a base correction of 3.5 EV. Is this correct?”

Smart Lighting could then move the Exposure Compensation slider 3.5 EV from wherever it was and then get busy adding sensible corrections or leave the Exposure Compensation slider alone and modify its own base EV correction (at which Exposure Compensation would react to the Smart Lighting changes).

A decision should be made here one way or another and carefully documented, to prevent all of us muddling through ISO invariant images with about four or five exposure tools (Exposure Compensation, Smart Lighting, Tone Curves, Contrast come to mind off the top of my head) without a clean workflow.

These are decisions for DxO to make and to inform us. Maybe these issues are already solved at a software level. From what you gentlemen wrote, there seemed to be some very solid solutions in place DxO Optics Pro 9 so the tech is there. It’s how we get to it and when in DxO Photo Lab 2 which is the question.

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Thanks for the explaination.

I can understand why from an imaging processing perspective DxO Smart Lighting v7 (as well as v9) is mutually exclusive with Local Adjustments.

However for my workflow (thousands of images of horses PER DAY of shooting) the DxO Smart Lighting v7 is the only viable tool.

When you shop for a new car you use the automaker´s online configuration tool to customize your new car. You select options you want, and every now-and-then there comes a dialog box informing you that the choice you just ticked will have to remove some other thing you already ticked elsewhere.

It is perfectly within the grasp of, and accepted by, car buyers that sometimes you have to choose one option the other, you cannot have all the options selected at the same time.

So with DxO PL, why not have a checkbox in the preferences settings that disables all local adjustments and enables DxO OP 7 & OP 9 style capabilities in the Smart Lighting panel?

(Either that, or PLEASE, pretty please, provide correction modules for modern cameras and lenses in DxO OP11)



Hi John-M;

I think DxO Photolab is not DxO Optics. It is different so we need to study how it works. I think we can’t just expect we move one or two sliders and the image is done. We need to use all those capable tools but we also need to know, how they work.

I’m studying DxO Photolab extensively; especially Spot Weighted Smart Lighting and Control points in Local adjustments.

Spot Weighted Smart Lighting is a very powerfull tool and it has some sort of AI. It is ‘smart’ tool. It knows how to preserve highlights from overblowing and it can also raise shadows and preserve contrast and details in that area. The image will look balanced and natural.

I think you should first use Spot Weighted Smart Lighting. Put one box on the chandelier and the other box on the upper window. Then slightly move those boxes for best result. If needed you can also put third box on dark area to lift shadows and expose those shadows details. Also adjust Smart Lighting slider for best results.

ClearView will also help you a lot. Try adjusting ClearView slider for best result.

The next step is Selective Tone sliders. The key is small movement. They are there to fine-tune the image so you need to be gentle – do only small movements of those sliders.

Next step are all those sliders in Contrast tool – especially Microcontrast and Fine contrast. They will enhance details and contrast (if some details are lost in the process). You can also enhance contrast in separate areas of the image (highlights, midtones and shadows).

Next would be Curves. You can adjust lots of things with curves – white and black point, shadows, highlights, midtones, contrast …etc.

The final step is to use Local adjustments. Try Control points. They have some sort of AI just like Smart Lighting. You can also do negative Control point to protect some areas.

If there are some problematic areas use Brush in Local adjustments. You can adjust only small areas of the image so you have total control.

Also try those DxO presets. They can surprise you and give you good image from the start. You can also change camera profile. Sometimes the profile for your camera is not the best option.


Haha, very good, m9k … Table nicely turned ! :grin::innocent:

John M

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Sorry, but I couldn’t resist.
No hard feelings, I hope…

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You forgot to mention the HSL tool… :innocent:

No, not at all … instead, I was impressed with the thoroughness of your retort.


Retort? Why retort?

By Google translate ‘retort’ is sharp and angry incisive reply.

I wasn’t rude and I wasn’t angry. I hoped my writing was some sort of mild sarcasm. Sometimes when I write how Smart lighting doesn’t work for some photos and I also can’t help it with those Selective tone sliders I get similar answers from this forum.

Would you say they are all retort to me?

Is it just me or you have discovered that sometimes Smart lighting doesn’t work?

How about that. I thought Smart lighting is all-in-one solution for all problems. I thought Smart lighting is essence of DxO philosophy; a pillar of DxO post processing ability. All I can hear on this forum is Smart lighting and Smart lighting and Smart lighting.

Now you say Photolab Smart lighting does not work OK? Well; how about that.

Yes; now I’m pissed.

Don’t get upset, I think John may have meant to express something different and used the wrong word to express it. Smart lighting is terrific. English is a very complex language, even for English speakers. :upside_down_face:


What is your native language? People write here predominantly in English (or possibly French) but that means others need to use Google or other translation tool - which are not always reliable. For example, the french word “courses” can mean either races or shopping.

Please don’t take offence at other people’s words until you have first checked you really understand what they intended to say, rather than assuming what can be an automatic translation is correct. Most people are here to help, not insult.

My native language is not English so sometimes I need to look at Google translate to find the meaning of a word or phrase…… like ‘retort’.
This is directly from Google translate – check below:


English is a group name like germanic language or Latin.
American, Australian, British, Scottish, Irish, Welchs, do I forget one?
Words can have a different load and meaning in different regions.

Dutch is related to German but not completely, because the Batavians and Frisians are the main group of early lowlands, the “Netherlands”, often overrun by Franken, Germanic people, Roman, you name it. Even the Celtics where on our shores for a brief moments.
We are stil here taken from everyone words we use and implement in our speaking and writing…turning it in a dutch word with it’s own meaning.
And vice versa. Sailing thermology most is dutch related.

See our history of de lage landen


As I indicated before, John most likely used the wrong word to express what he was trying to say. It happens very often in English. Although I pride myself on my English skills I will occasionally use the wrong word to express an idea.

To give you an idea of the complexity of English word usage, the following list of words are all synonyms for retort. They all have some similarity to the various definitions of word retort, yet each can also mean something completely different.

  • quip
  • rejoinder
  • repartee
  • antiphon
  • comeback
  • cooler
  • counter
  • crack
  • gag
  • jape
  • jest
  • joke
  • lip
  • reply
  • reprisal
  • respond
  • response
  • retaliation
  • return
  • revenge
  • riposte
  • sally
  • topper
  • wisecrack
  • witticism
  • back answer
  • back talk
  • parting shot
  • snappy comeback



Never, never, never take Google as a source of good translation. As Mark points out, the number of possible translations for all the possible synonyms is beyond anything Google can comprehend.

Basic definition from the Cambridge dictionary : to answer someone quickly in an angry or funny way

English is also generally considered to be the language with the most words in current usage, 170,000. Most native English speakers only know and use a small fraction of them. Add to that is the often confusing syntax and the many “rules” which also have many exceptions to them, You have to forgive us native speakers if we occasionally use the wrong word, or use the correct word but express it in the wrong context,

In any case, I think its probably time to get back to the original intent of this topic.



As a native English Speaker (U.S. Southern) I saw nothing in John’s reply that conveyed ill will. The whole sentence has to be taken in context. The wording that precedes the word retort are all modifiers for the word retort in this case. “no, not at all”, told you there were no hard feelings and “instead, I was impressed with the thoroughness”, told you your reply was very detailed and with merit. So please don’t take offense to John’s reply.


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No; I’m not taking offense. I just saw the first meaning Goolge translate gave me. I think it’s best to just forget about it. The second I made a reply I regret because John is polite person so it’s my fault I didn’t understand him correctly.
In my post I was just trying to be slightly sarcastic. I couldn’t resist … you know … when I say those DxO sliders does not recover as much highlights as Lightroom, then I usually get answers like: use Smart lighting and then use Smart lighting and at the end just a little Smart lighting and then Control points and Contrast and Curves and Brush and ClearView and Gradient tool….etc.
As you can see I have some mixed feelings about Smart lighting. Yes; it’s a nice tool but not all-in-one solution. Those Selective tone sliders should be more capable so I don’t have to use a bunch of other tools as I don’t need to use in Capture One or ACR or Lightroom or On1. Yes; I also have On1 for a few days and Highlights slider with new 2020 algorithm works just beautifully.

And about my reply to John…
When I posted my cat photo he suggested me a few times to use Spot weighted Smart lighting with rectangles. Now I saw this thread and he is telling that Smart lighting and those rectangles does not work on his photo. He is describing the same problem I described in some of my therads/posts.
I’m very glad one of more influenced forum members mentioned this. On the other hand I’m also surprised he didn’t get advices like I did… ‘’move Smart light rectangles’’; ‘’use Control points’’ ‘’use Brush’’… and similar. It looks to me like all of you somehow agree with him about Smart lighting limitations.

Like John mentioned (and I agree with him) sometimes Photolab Smart Lighting doesn’t work as good as someone would think or wish. I also discovered this for some problematic photos. It just doesn’t work no matter how you ‘move those rectangles’ around the picture. Then you need to solve the problem with Local adjustments because you also can’t do it with Selective tone sliders. It’s nice tool but it’s not perfect and it certainly could be improved.
I for sure can’t understand why would Smart Lighting affect midtones and shadows if I put a rectangle only on most left pure white column. It effects all other things except this pure white column.
I’m talking about a file with stripes from pure white to pure black someone posted on this forum.