Thanks. But if that feature is meant for the display-referred workflow, relying on base curves, don’t the base curves replicate the ‘camera look’? If I remember correctly, they are created by comparing the embedded JPG with the demosaiced raw.
basecurves is ‚one size fits all‘ stuff - not a per image comparison to the embedded jpg.
So setting an initial exposure based on the embedded jpg is just for those who want to use exposure compensation like in old slide photography times and expect an initial exposure like the cameras jpg processor does.
That feature is independent of display or scene referred workflow - it’s just the mindset and habits of the user who wants to use exposure compensation in a different way then the designer of the scene referred workflow recommends, maybe to get also proper jpgs out of cam. Different users, different expectations…
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No, I don’t use .jpg in camera, but .DNG. It only unnerves me, that in the field I adjust exposure correction for a realistic image and then in DT I need to correct exposure once more, because the exposure Module resets the correction.
Of course I could go ahead and expose by camera lightmeter and then add exposure later in DT. However that would also create noise and that doesn’t sound like a good idea to me.
Thank you! You fully undestood my intention.
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Good to hear!
I had really liked to have it for my normal, i.e. high quantity, not-so-technically-demanding pictures to increase my editing speed in darktable. Would be a really nice workflow improvement and probably also make a lot of new users less confused about what darktable does to their images.
@MStraeten the improved exposure-picking-tool seems nice but would it actually be possible to use for a what-you-see-is-what-you-get default initial exposure? You would need to always have a known grey patch in the image? The new feature matches a spot to the desired lightness value if I understand the PR correctly (note, haven’t tried it yet so could be wrong).
What I imagine is having exposure-normalization on a per camera model basis or similar. It should for example not fail even for pitch-black lens-cap-pictures or overexposed forgot-to-reset-my-iso-setting-from-last-nights-low-light-session-pictures. You can not rely on only one unknown image on those but would need to match the middle grey value externally, f.ex. similar to how the noise profiles are made.
you can use arbitrary areas in source and target image that should match after automagic exposure matching. No need for grey patches.
so for an initial exposure setting to take manual in camera exposure compensation into account it might make sense to use the embedded jpg to define the reference exposure - maybe by selecting an arbitrary area or an average of the whole image.
Actually tried out the new matching function and I think the jpeg tone curve might cause some problems with the matching for values very different from middle grey. I’m actually a bit surprised it’s implemented as a perceptual matching as that isn’t possible to guarantee with all modules that come after. Would be more robust to just give an average target (could be defined as relative EV steps from middle grey maybe).
Anyway, my hypothesis is we could do camera jpeg matching on a per-camera model basis instead of on a per-image basis. More work for us developers but more predictable and more robust for the user. I’m basing this on that you will get the same image if you take two pictures with the same settings, i.e. it’s constant over time and cameras!
Doing auto magic per picture might work but there is a risk of it not being exactly equal every time which wouldn’t be optimal in my eyes!
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But that is going to miss the point about the automatic correction of user-applied exposure correction. There seem to be two “camps” there:
- use the in-camera correction to get the best use of the available dynamic range (so dt should compensate for that)
- use the in-camera correction for creative purposes (so dt should not touch that user choice)
Which brings us back to the issue we started with: some users will still have to define their own presets.
Let’s keep in mind that dt is a tool which provides a lot of customisation options already. In this case, it seems clear that in practice that everyone using filmic has to use the exposure module. And we see two incompatible use cases. So why not leave as is and promote the use of user-defined presets adapted to ones own preferences and habits?
Also, how do you see the use of the jpeg-matching option: activated by default, or optional? in either case, some will have to enable or disable that according to their habits/workflow/preferences. Which means that you just move the decision point for the user
Calling deviation from the camera suggested matrix metering creative is quite a stretch of the word creative. (I know it’s been used previously in thread) Or rather it shows incredible belief in the intelligence of the metering system. So much so it would require direct brain to processor connections.
As I’ve said in other threads it relies on the provably false assumption that noise and lost colour fidelity aren’t a thing.
Not relevant for the current discussion… It’s what some claim they are doing. Right or wrong, that’s the way they want to work.
All I was trying to say that any proposed solution will be “wrong” for some users. But switching off the current behaviour is possible with a user-defined preset. So why complicate a simple tool? And how would the new option work/not work for those that do not want it?
And this is not just about this tool. In general, I prefer having the technically correct option as default. The possibility to save my own presets and styles allows me to adapt that behaviour when I want or need to. And when some of those adaptations are technically incorrect, that’s my choice (hopefully made for a good reason…).
“Technically correct” doesn’t apply to how people use exposure comp. Again, the idea that default matrix metering exposure is always the technically correct exposure would shock most photographers. I actually can’t understand how anyone who has ever used a camera can think so.
For the record I agree that users will have different needs and an config to set it is a good solution.
@nosle At least put quotes in their proper context, you skipped the bit just preceding the bit you wanted:
You’d hope its optional, as I’ve set my in-camera jpeg profile to “flat” and I ETTR most of the time, so the jpeg doesn’t look great on a lot of my shots anymore.
There’s an intentional workflow (scene referred) which is base of the current development. So any default settings of options should contribute to this workflow. That’s a guiding principle for good user experience.
If a user wants to use darktable in a different way, he of course can do, but it’s a bit foolish to expect darktables defaults to be oriented that way.
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I’m not sure about what your intention is with this comment Martin. What I had liked to see is an improved scene-referred editing experience where the raw data is normalized such that the raw value corresponding to middle grey in the jpeg is normalized to 0.1845 per default. I think this would be an improvement of the behavior for the scene-referred editing making it more widely adopted.
@rvietor no default is also a default. But first, some questions for you because I need to understand your perspective on the topic to better understand your comments.
- What kind of photography do you generally do? Landscapes?
- Is the current default of +0.5 EV in the exposure module ever the correct value for you?
- Have you created a preset for your workflow?
I do not think you can define a “technically correct option” here. We can only think in terms of statistics (maximize the probability of the default exposure being correct for any photo and user) and user expectations (minimize surprises, design following WYSIWYG is a good method for that).
We have RAW data normalized to [0, 1] that represents our scene that we want to edit in an unbounded [0, inf) space. Defining middle grey as a normalization point and matching that with what the camera outputs is a robust way to normalize RAW data such that every camera out there delivers the same experience.
Power users like yourself and Mica who value the maximum performance of their cameras over ease of use in the field and editing speed are still able to add presets following your personal ETTR habits.
Would you be interested in trying this out if I tried to implement it in a simple form? Because I’m actually not trying to tell a developer to do this for me but I’m rather trying to feel if there is a will for functionality like that and if I should try to contribute it!
Do you have statistics on how many people prefer the current default, or would prefer your suggestion?
Maybe this could be supported by a preference (just like we have for workflow, chromatic adaptation, auto-application of sharpen), and then everyone could set their defaults there without creating presets (which is more cumbersome, especially for newcomers).
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I so wish I had some statistics on it! I thing its mostly a nice way about thinking about development as “technical correctness” sometimes isn’t very well defined.
The +0.5 EV is almost never right for me. Auto-compensation, never, because those cases where I had the need to use the in-camera exposure compensation have shifted the focus to trying to fit a given dynamic range within my camera’s capability. A manual adjustment has thus always been needed for those pictures.
But I see the possibility of making a large chunk of easier pictures work on default settings if the middle grey was normalized to match the jpeg.
Exposure normalization could be added to the user preferences but I actually think that would be superfluous as anyone who uses their cameras to the technical limit will find the current default of +0.5 EV as wrong as a normalized version.
The auto-compensation thing should be a preference though! I might begin by adding that.
I’m generally between 0.5 and 1 stop, depending on what is in the scene.
Not for exposure.
I’m not sure what this means. I don’t shoot anything that is consistent in light or subject, so I need to hand edit exposure and filmic every time to get a consistent look yl my work. A preset of those two modules would never work and would look bad.
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Nature: birds, insects, macro. With the birds I can get anything from shade with no extreme highlights to close to backlit.
No, when I have a correctly exposed camera jpeg (i.e. midtones about correct), I need ~1 EV compensation. In backlit situations up to +2-+3, but I try to avoid that.
Yes.
I wouldn’t define myself as a power user. But I do feel at ease with the technical aspects of both my camera and darktable. And I’m not afraid to read some more technical texts, perhaps related my background in science (chemistry and CS).
First of, that remark was not limited to the exposure module, but more in general (as I already explained to @nosle…).
Now, as to the exposure: as I see it, when you use exposure correction in-camera to e.g. protect your shadows or your highlight, that will shift the exposure of your mid tones, which is not what you want. And the in-camera jpeg will be off as well! So it seems logical for me to correct that in the exposure module as a first step.
But if you use the in-camera exposure correction to get a good looking jpeg, you do not want darktable to remove that correction.
And crucially wrt. to your proposal, you cannot use the in-camera jpeg to set the exposure if you use the first of those techniques as that jpeg is incorrectly exposed (intentionally).
For me there’s an additional obstacle, in that I rarely have a nice patch of middle gray available in my images (and picking a coloured patch of proper luminosty isn’t easy either). So, no, I don’t think I’d use a method to pick the exposure form the in-camera jpeg. (and I have set the option to use raw instead of jpeg in lighttable settings to “always”, so I can see what’s to be done)
I actually have a style that I apply to new edits, which sets a few modules I almost always need/want: noise reduction on, highlight recovery off as it plays havoc with reds and yellows (it considers whitebalanced intense reds overexposed too fast…).and a few things more (basic sharpening and such) And then adding presets for exposure and filmic (lower contrast!) doesn’t cause any extra work, while getting the initial edit closer to what I want. The values used in that "starting style " are based on what I find myself using most of the time.
And with the Xtouch mini, correcting exposure, and filmic white and black, is fast (just turn a know wherever you are in the darkroom; sometimes it’s too easy, and you overshoot…)
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