darktable : jpeg from camera consistently look sharper than raw

Hello,
I’m a very casual/beginner photographer and darktable users. I shot with a sony alpha 7II and a 35mm lenses, and i’ve been slowly learning the basis of darktable and as an exercise i tried to mimic rendition of the camera jpeg using darktable then scratch everything and try to do what i want.
Doing that i noticed that the jpeg of street photography/landscape (usually with quite high dynamic range) always look sharper than the darktable version.
My pipeline usually looks like : denoise → chromatic aberatton → exposure → filmic rgb → sometimes local contrast → sharpen.
It does not seem to be a contrast issue, and although sharpen/local contrast helps regaining some level of details, it never reaches the level of the camera, especially in tree leaves. It does not seem to be a problem of range compression because it is usually in the flat part of the S curve.
Any idea why it happens ?

for sharpening images I use the profiled denoise with default setting (reduces sharpness only a tiny bit) and the contrast equalizer.

In the contrast equalizer I increase luma and edges for finer details (right side of the diagram) like this:
Bildschirmfoto%20von%202020-01-04%2011-10-46

I remember doing this to A7 RAWs for some PlayRAWs with good results. Sometimes I move this bulge more to the left/right or make it stronger, depends on the image.

P.S.
If you want you can post a RAW as a PlayRAW here and you’ll get many (sharpened) examples from other dt users with corresponding XMP files.

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Have you inspected the camera settings to see what sharpening the camera is applying? The camera JPEG engine and darktable pretty much start with the same raw data, so it’s probably about something the camera is adding, not something darktable is taking away…

Can you supply the raw and the ooc jpeg?

Just my two cents: make sure you’re comparing images of same size and same zoom ratio.

I agree with @pphoto on using the Contrast Equalizer for increasing sharpness. I do not use the Sharpen module anymore as I believe CE does a better job. I think in recent discussions on RGB pipeline the Sharpen module was discouraged. I sometimes use 2 instances of CE presets - the one for sharpen (or denoise/sharpen), and second for clarity. For both, I find the default settings quite strong, so either lower the effect or use a uniform mask and reduce opacity.

Like others have said, posting the raw files would allow people to edit and post their versions with xmp sidecar files. I’ve found this to be a terrific way to learn new techniques that others use.

Same problem here. I’m shooting Olympus e-m5 mark 1 and the the raw images look dull compared to in camera produced jpegs. This just stared to happen since Darktable updated from 2.6 to 3.0 (Linux) without asking me.

Raw files are more or less direct outputs from the sensor. The camera manufacturers know their hardware and use special algorithms to “develop” the images. Programs like darktable allow the user to do this manually.

What distribution are you using? The upgrades are normally done by the maintainers and not by “darktable”. If you are using a rolling release like Archlinux, upgrades are the normal behaviour.

All just speculation. Like I said, both the camera JPEG software and darktable start with the same array of light measurements, so work forward in each and look for the specific differences.

+1. This is where it starts…

Xubuntu 18.04
I was hoping to wait a bit before upgrading so I would have time to learn version 3.0’s quirks and peculiarities. I was still struggling to understand version 2.6. I spend entirely too much time reviewing youtube videos about Darktable.
I’m still trying to find time to understand all the modules DT automatically applies to the raw images.

JPG’s also have very aggressive sharpening and local contrast settings usually and perhaps boosted saturation so its not unexpected that they will look sharper and better…zooming at 100% or greater can start to show this aggressive processing…usually you start to notice some of the edges where the tonemapping and sharpening has happened…raw files can save you if the jpg files are grossly under or overexposed or have color issues because the data is unprocessed but they don’t benefit from the custom noise reduction applied to jpg files by the camera and in my experience it is pretty hard to hand the noise and still get tack sharp images…I think raw files will more often than not be softer than the corresponding JPG file…

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@River_Man, Auto-apply sharpen is now an option in “Core Options.”

Hitherto, I always got Orientation / Base Curve / Sharpen in the history stack from a fresh import.
Things have moved on a great deal, but you can still enable the auto-apply of sharpen.

Of all the DT modules, I have the most difficulty wrapping my head around the contrast equalizer. I use a similar profile as yours… I have a fairly good handle on the luma controls, but I still can’t get predictable results from the chroma tab and the edges control doesn’t seem to do anything for me.

Operator error, no doubt, but not for lack of trying. :thinking:

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Hi @Dave22152,

Yes, the contrast equalizer module can be a bit confusing.

Start reading the darktable user manual, section 3.4.4.2 Equalizer.
Then watch Bruce WIlliams’ darktable episode 024.

After that, take one of your own images and test the module’s curves. Begin with a low ISO image, and when you feel more proficient, try your skills with a very high ISO one…

Don’t make your moves too intricate at first, start by grabbing the Luma curve (curve? hm… it starts as a line) in the middle and drag it upwards. Watch what happens. Drag it downwards. Watch what happens. Switch grabbbing area. Alter width of effect by mouse wheeling. Watch. &c.

Have fun!
Claes in Lund, Sweden

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Hello, @Claes, I’ve gone through the manual and video and am slogging through the controls as you suggest. As I said, I think I know what I’m doing with the luma tab, my problems have more to do with the other two.

With chroma, the results are either wild or imperceptible. With edges, frankly I can’t see what it does at all. I seem to recall that Bruce Williams even admitted that he couldn’t seem to get any different using that tab

I think it’s like a lot things… if I knew what to look for with chroma and edges then the adjustments would become obvious

Thanks for the advice

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@Dave22152: One of the things I did to help myself was use a difference blend mode to see what is actually happening while you change the settings, 'cause it’s not always easy to see looking at the image (especially the chroma tab changes).

Although this post only concentrates on the luma tab, it can also be used with the chroma tab.

Knowing about the details of it all is rather important, so do follow @Claes’ advice.

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@Dave22152: please try the Dutch Diff method, as outlined in Jacques’ thread, above.

Let’s not forget that for sharpening one can also use the Highpass module with the method I learned from Hary Durgin videos:
Sharpen edges:
- Sharpness: any (adjust to low enough to see only the edges of objects)
- Contrast boost: any (same as Sharpness)
- Use Overlay blend mode
- Opacity: control the effect

@Jade_NL and @Claes, that advice helped a lot. I was looking for a way to discern the changes and the difference blending was precisely what I needed. Now I have the tools to figure this out on my own. Thanks again!

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@Dave22152

You, sir, can be sure to get great service every time. Because here at Pixls & Us, we aim to please.

Seriously though: You’re welcome.

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