[Play Raw] Enhance snowy mountain detail (high-frequency high-contrast) in RawTherapee

Those were the days, going skiing…
Here’s my effort mainly using a Lab tone curve.

Here’s the curve -

@Chymera, this may be of interest -

I see the Nikon jpeg has managed to suppress the lens flare rainbow top centre whereas the rest of us haven’t.


With Haze Removal and more Lightness -

Indeed i’ve noticed too the lens flare rainbow suppression, this is the first time i see such a feature!

My first edit in RT was difficult. Was hardly able do improve it at all.

I also tried to erase unwanted reflections in the picture. Where is the spot removal/healing brush tool ? I can’t find it …

Then I tried to do some edit in DxO , and realized it is possible to restore the sunny green color in the trees.


Then i tried for more than one hour to do the same in RT. This is what I could do in RT 5.5

I guess a more experienced RT/dt user could do a lot more than me.

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Yeow, that was tough. The “thing” seems to be to get the halo around the sun to blend, rather that just blob out.

I tried RawTherapee first (don’t code on me, @Claes:smile:), but I’m not color-managing it yet so what looked okay in-program didn’t look the same exported.

So, I reverted to rawproc, opened it with dcraw ProPhoto colorspace and gamma, and build a rather challenging curve to do the “thing”. Bit of saturation, then resize/sharpen for output to sRGB colorspace. Let’s see how it looks out there:

Here’s a screenshot to show the curve it took:

Ok, this was a challenge…

I’m aware this isn’t a PlayRaw and the thread is actually about rawtherapee, but I just couldn’t resist giving it a try in darktable. Sorry! :smiley:

camera.NEF.xmp (6.0 KB)


Here is an attempt with darktable and a bit of gimp:

camera.NEF.xmp (19.3 KB)

I think one of the problems in your attempts is that you lose a lot of detail to noise reduction. Curves + a bit of local contrast should get you pretty far already. With that said I always struggle with the local contrast in RT. :slight_smile:


@Jonas_Wagner, how did you avoid the coloured flare streak please? Gimp?

Didn’t do anything to it, from all I can tell it’s still there. And looking at the image again a bit after editing, I guess I went a bit too crunchy and contrasty but oh well. It was about enhancing detail after all. :slight_smile:

I just curve-dragged it into clip oblivion. Above a certain point, everything is just white… :smiley:

Seriously, I’ve found that images with saturated pixels require such treatment if you do your processing “by hand” - white balance, in particular, separates the saturated channels, and the only realistic way to corral it is to set the white point at the lowest of the histogram spikes.

I noticed that this thread has been tagged #play_raw. If this is something that you want @Chymera, could you also supply a license for your images? (Unsure, since you weren’t the one who added the tag…) See: PlayRaw stuff to keep in mind.

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I meant the bright colour has gone, just wondered if you’d used a healing brush or clone tool etc. in gimp.

Ah no, I didn’t do that. I guess they were just clipped out as Glenn suggested. :slight_smile:

Tough one. I did use a Nikon camera for a while. A number of people use Nikon’s raw converter and export as tif for further work. Nikon use an unusual method of converting raw files. :laughing: So having been there before and not being able to get a conversion I liked from RT I used Ufraw as it has the same facility Nikon use and exported a 16bit tif. Light into the lens has fogged the shot so used Fotoxx for further editing. Lastly add a bit of chroma via RT.

Sorry it’s not an RT solution but without the facility the first curve from the left in Ufraw offers I don’t think this sort of result is easily possible.


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with darktable 2.60

camera.NEF.xmp (24,3 Ko)

My take.

1. PhotoFlow → HL mode (blend) → AMaZE → linear Rec2020 (no clipping) → tone mapping → linear sRGB 32f
2. gmic → filter pixels → crop (1.5:1) → wavelet split (residual [A], detail [B])
3. pnmclahe → enhance (A)
4. gmic → wavelet merge (A B) → adjust brightness, contrast (curves) → local contrast, sharpen (guided) → increase chroma (curve) → sharpen (LoG) → resize
5. GIMP → clone out flare above sun

Zoom 100% and enjoy!

Edit: correct version

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My take
tonecurve, dynamic range compression, Lab LH and CH for trees, dehaze, Wavelet local contrast

camera-4.jpg.out.pp3 (13.5 KB)

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Very late to this challenge.
I used RT and starting with Automatched curves - ISO low profile I only did few things:

  • shifted the blues slightly towards the purple
  • added the L curve in the Lab Tool with very slight adjustments
  • added local contrast

camera_RT.jpg.out.pp3 (11.9 KB)

After a first export and shifting directly between the out of camera image and mine it was apparent that the camera is adding some local contrast. So i experimentend with the radius until I got a similar result. The radius can kinda be seen at the transition sky to mountain on the mountain part.


That was a hard one.
Here is my attempt, where I concentrated to get rid of the flares…
dt 2.7

camera.NEF.xmp (49,2 KB)

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