DNG Linear Profile Help

I have a new smartphone (Samsung Galaxy S23 Ultra). It has RAW (DNG) output that is “linear profile”.

I can start with Neutral profile. But it will be great if there is profile that gets me to a decent starting point. I also tried Bundled profiles. Auto-Matched Curve is closest to reasonable, but it is overexposed. Yes, I can edit that overexposed image, but I find it much harder to edit.

Is there some place to download a profile that kind of work for this “linear profile”? Or make my own? And I need some guidance, pointers, or direction here on making my own.

This is the example DNG file on Google drive:


Although I have been shooting and editing RAW for over 10 years, I am complete noob when it comes to Camera Profiles. I always just used the default camera profiles. And I don’t edit much. 95% of time, I just use SOOC JPEG. Maybe 5% of photos, I will post process the RAW images.

If I have a choice, I would not want to use this “linear profile”. The issue is that I’m trying to take a single capture on this Samsung phone that will provide both usable JPEG + RAW for backup edit. Samsung has 2 different camera modes that can output RAW.

  1. One mode is called Pro mode. The RAW (DNG) image is like typical RAW. But the JPEG output is very similar to RAW. Flat, underexposed, muted color. Which means the SOOC JPEG is often unusable as-is.
  2. Another mode is called Expert RAW. (Yeah, pretty stupid names. That is marketing!) The RAW (DNG) image is linear profile. The JPEG is processed, so it is much more usable. I would like to use this mode, so I can have usable JPEG, plus the RAW to work with in case I need it for select photos. Unfortunately, I have to deal with this linear profile.

Hi @D00M,

Just for fun, how does this simple profile work
at your place? test.pp3 (13.8 KB)

Have fun!
Claes in Lund, Sweden

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If you can run windows then download the Adobe Profile editor. You could add a custom tone curve and tweak colors and save and use that… There are lots of videos messing around with it…might be worth it…

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It also looks like that file expects about a 3 EV exposure bump from the exif data…doing that and adding the std adobe curve is not too bad of a result…you still need to add more color/saturation…

Edit… if you use auto levels it adds about 4.5 ev Then disable the automatch curve…it seems a bit extreme.

I added a couple of more things… Abstract Proile sRGB preset, and default enabled tone mappings and added some vibrance… Seems like a pretty simple recipe … you can also punch this up with RT dehaze which really enhances saturation maybe more jpg like…

Or no abstract profile and autolevels again, Adobe tone curve, default settings for log tone, dynamic compression, dehaze and vibrance at 20… so similar to above

DCP_tone_curve.rtc (44 Bytes)
20230529_090128.jpg.out.pp3 (14.6 KB)
20230529_090128-1.jpg.out.pp3 (14.7 KB)


Hi Claes and priort,

Thank you for the fast feedback. I tried your profiles. Looks fine, and I do need more time to play with them.

I do have couple general questions. Please bare with me as I am new to RAWTherapee and I don’t have much experience with profiles.

  1. Profile vs Auto Levels?

For a normal RAW image, I first use Auto-Matched Tone Curve profile, which is set as my default for RAW. Next I use Auto Levels. Then continue with my custom edits.

For this linear profile DNG, if I use (Neutral) profile, I can use Auto Levels. If I use Auto-Matched Tone Curve, the tone curve is significantly changed. Then Auto Levels cannot be used as it will cause the histogram to shift severely to the right and be clipped.

I can use only one or the other: either Auto-Matched Tone Curve or Auto Levels. Are there pros and cons with either method?

  1. priort, you mentioned Adobe tone curve, and you attached the DPC _tone_curve.rtc. Is this a standard or typical curve from somewhere? Just trying to learn when and where I should use this.

Thank you

Pretty much the generic Adobe curve and I got it from Rawtherapee website… I think automatch is good if it works out of the gate but if not you might be better using fixed controllable modification… The automatch is going to keep changing whenever you modify a module that gets processed before it… For some camera’s if you leave it on and use the tone curve in the DCP then it almost becomes a strait line… THe thing is your files are expecting a significant exposure boost… How you manage that I think is the best thing… then you can to tone and color… I played around quickly with a couple of other ways after adding all that exposure… As I mentioned you image has a base exposure of 3 in the meta data but I found something more was better… THose files are sort of a weird proprietary configurations… You can tell that from the black and white points which are 0 and 65545 or something like that so more like you would see with a TIFF…

I am more familiar with DT and these files present a bit more like DT edits… you need to add exposure color and tone to these images as its not applied by a profile in the software or it would seem embedded in that file… In DT I have the exposure set to give me an auto exposure and others use a fixed offset as a base and they add to that… in DT you are trying to expose the midtones so its a little different approach…

“linear profile” - seems like a variation on “linear DNG” - while MOST DNGs are linear, “linear DNG” is often used to refer to a DNG that has been demosaiced but is still linearly encoded and in camera-native color space.

The embedded profile in the DNG should be just fine.

Keep in mind that the JPEGs from nearly every phone camera on the market have had local tonemapping applied. Anything that has had local tonemapping applied will NOT be usable with AMTC. How you described this implies to me that this is indeed such a file, and the likely reason it is demosaiced is because it was generated by a motion-aware stacking algorithm similar to Google’s multiframe superresolution (used in Google Night Sight, etc).

If local tonemapping was used matching the JPEG exactly is impossible without knowing exactly what tonemapping algorithm Samsung used. All I can tell you is that Google Pixels use a variation on Mertens exposure fusion algorithm - multiple synthetic exposure-shifted JPEGs are generated from the raw data then fed to fusion. You can emulate this by generating multiple exposure-shifted JPEGs in RT and feeding them to enfuse.

Alternatively, try the “Standard film curve” presets and add the Dynamic Range Compression tool to the mix. Fattal '02 (the algorithm used in DRC) isn’t as good as synthetic exposure fusion, but it’s more than enough to do the trick in 95%+ of my use cases.

For what it’s worth, I NEVER use AMTC. The only reason to use it is if you want to try and match a particular camera’s tone curve EXACTLY, but there are a wide variety of reasons (vignetting/distortion correction, local tonemapping, differences in specific curve implementation) that attempting to do so will fail.

Thanks Entropy.

Similar to what you mentioned, there are 2 different “linear” terminology. One is the linear DNG format, where the RGB data is already demosaic’ed. Another is the camera profile, where it can be standard profile vs linear profile.

Just want to share this here, in case anyone else use RAWTherapee with Samsung smartphone DNG outputs.

Samsung S23 Ultra smartphone has 2 modes that can output RAW (DNG) files.

(1) Pro mode:

  • Format is linear DNG
  • Camera profile is standard

Apply bundled Auto-Matched Curve or Standard Film Curve profiles. Below is what the tone curve looks like, for each case. Both are usable, and then continue with normal editing.



(2) Expert RAW mode:

  • Format is linear DNG
  • Camera profile is linear.

Do not use Auto-Matched Curve. Resulting tonal curve looks like this. It is still usable, but just odd. It takes time recover from this to a normal starting point.

And when the exposure is off, the tonal curve is even more weird. This is an over-exposed photo using Auto-Matched Curve profile:

Both priort and Entroypy512 suggestions work for this linear profile. And they get to the same results.

Start with (Neutral), no profile. Use Auto Levels, which brings the histogram to center. Then apply the DCP_tone_curve.rtc (Adobe tone curve). priort attached this tone curve file above. Can also download from Exposure - RawPedia

Alternatively, use bundled Standard Film Curve (which applies same tonal curve as DCP_tone_curve.rtc). This is the result.

Apply Auto-Levels. Then both methods get to this great starting point to continue with normal edits. This is the tonal curve and histogram.