raw tone curve

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raw tone curve

I have some basic questions for the raw tone curve in Lightzone:

1. If I found the raw tone curve panel when I open a raw (for example, D800 NEF file), is this raw tone curve embedded in the raw, which is provided by the manufactor (e.g. Nikon), or is it just from some user adjusting profile?

2. I can save the raw tone curve as some style and read the data. It has something like "<Points Size="16"> <Point X="7" Y="0.43805"/> <Point X="11" Y="0.70354"/> </Points>". Is the X value in a range of 1 to 16?

3. When plotting these raw tone curves from different Nikon cameras, I found they are very different. Some are close to linear, while some are quite far away the 45 degree line and not quite smooth. It seem strange to me and wondering if they are really from Nikon.





No, this RAW tone curve (RAT)

No, this RAW tone curve (RAT) was created by Lightzone team. It is, in principle, specific to each camera model.

By the way, sometime, a camera RAT could be used with another camera model RAW files, but it's not made made for that and can give ugly result if camera are very different (not the same sensor for example).

Is there a way I can get the

Is there a way I can get the original tone curve inside the RAW file (e.g. Nikon's NEF)?

I think you will find that

I think you will find that the only thing inside the RAW file is a small jpg thumbnail.


That will have been produced in camera suing whatever the settings are for jpg files at the time.


If you use the Manfucturer supplied software you get their engineers' interpretation of how the file should look. Whether they sell that Intellectual Property to other software developers I don't know. I doubt they give it away so that leaves non-affiliated developers to work things out for themselves - especially the Open Source projects.


The only way you are likely to get the original Nikon interpretation(s) would be to use Nikon software to convert the NEF file to TIFF or DNG (thus retaining some of the RAW interpretation potential that jpgs will have "fixed" already) and then edit the resulting TIFF or DNG files with your editor of choice.









It should be possible since

It should be possible since Capture NX D was released and free. There's nothing to see with Capture NX 2 which was a wonderfull Nikon raw editor, but it should be able to develop NEF as in camera. The bad thing is Tiff are really huge files on hd. 

Raw Tone Curve

My lanuage is normally German. So

On Youtube you can find a File: Lightzone creating a RAW Tone curve. That is a discription of How to do. For User who speak a little German follows a Step Sheet change the Raw Tone Curve in German. Maybe it will help.


Youtube        lightzone:Creating a RAW Tone curve


1.         Laden einer Raw Musterdatei:



                        Wähle unter Camera Review den Hersteller.
                        Wähle die Camera.
                        Gehe zum Camera Review Pulldown-Menue
                        Unter Thumbnails findet man RAW Testaufnahmen.

                        Die gewünschten RAW Files downloaden



2.         Lightzone öffnen und die Testdatei öffnen.

3.         Zonemapper öffnen und einen Namen vergeben.

4.         Einstellen des Zonemappers auf RGB.

5.         Umschalten auf BW

6.         Anwenden vom Blur/Weichzeichner   (~10)

7.         Anpassen der Gradationskurve.




Anpasssen der Gradationskurve:


In der auf SW umgestellten  Farbtabelle habe ich rechts sechs Felder von Weiss bis Schwarz.

Ich öffene den Zonemapper“RAWToneCurve“ indem ich mit der rechten Maustasteb auf  dem Balken das Pulldown Menue öffne und auf Unlock stelle. Dann kann ich die Gradationskurve anpassen.

Ich schalte das „Zones“-Vorschaufenster und bewege dann den Mauszeiger rechts über die Grauwerte. Im oberen Feld wird dann das entsprechende Feld angezeigt. Durch den linken Mausklick wird dieser Grauwert festgestellt. Erkennbar an dem kleine Kreuz außen.


Ich schalte auf der Toolsseite in dem Vorschaufeld den Sampler ein. Er zeigt die Werte der Farben an. Wir beachten nur die RGB-Werte. Wir verschieben die Linie so lange bis die RGB Werte den Werten in der Tabelle entsprechen.

Man sollte die Folgenden Werte erreichen:


etwa 5 oder kleiner






etwa 240 bis 255








Diesen Vorgang wiederholt man so lange bis alle Farbstufen eingestellt sind!


Dann werden die Umstellung in SW und Blur gelöscht.

Wenn das Testbild dann wieder farbig ist, geht man mit der rechten Maustaste auf den Balken und aktiviert im Pulldown-Menue LOCK.


Die Gradationskurve wird dann für alle Bilder hinterlegt.


Thank you very much.

I will find a way to promote this message for our German language speakers to a spot where they can easily find it in the future.

1. Load a Raw pattern file

I didnt check this recource:


1. Load a Raw pattern file from:     http://www.imaging-resource.com/camera-reviews

                        Select the manufacturer from Camera Review.                         Select the camera.                         Go to the Camera Review pulldown menu                         Under Thumbnails you can find RAW test recordings.                         Download the desired RAW files (test files)          E.G. For pentax K5-IIs http://www.imaging-resource.com/PRODS/pentax-k5-iis/pentax-k5-iisA7.HTM 2. Open Lightzone and open the test file. 3. Open zonemapper and assign a name. 4. Set the Zonemapper to RGB. 5. Switch to BW 6. Apply Blur / Blur (~ 10) 7. Adjust the gradation curve.  



Adjustment of the gradation curve:

In the color table changed to BW, I have six fields right from white to black.

Open the Zonemapper "RAWToneCurve" by opening the pulldown menu with the right mouse button on the bar and set to Unlock.

Then  adjust the gradation curve. I switch the "Zones" preview window and then move the mouse pointer to the right over the gray values. The corresponding field is then displayed in the upper field. This gray value is determined by the left mouse click. Recognizable at the small cross outside. I switch the Sampler on the tool page in the preview field. It displays the values ​​of the colors. We only note the RGB values. We move the line until the RGB values ​​correspond to the values ​​in the table.

The following values ​​should be achieved: About 5 or less 23 49 91 152 About 240 to 255

Repeat this process until all color grades have been set!

Then Delete the conversion to BW and Blur. If the test image looks correct once it is in color again, use the right mouse button to go to the bar and activate the pull-down menu LOCK. The gradation curve is then stored for all images.

Freely translated please check