Noise pattern with Fuji X-trans RAW files


#1

When I open Fuji raw files (.RAF), I get a noise pattern in the image which I do not have when opening the same image with a Fuji Raw converter.

This picture shows a detail of a blue sweater in the Fuji RAW converter.

The second picture shows the same detail in RT, with the noise pattern visible.

This screenshot shwos the settings, RT recognises the X-trans sensor and the 3-pass method gives the best result, but not as I expect it to be.
Can someone advise how to remove the noise pattern ?


(Mica) #2

Have you tried some of the denoise options in RT? It is likely that the Fuji converter is applying noise reduction automatically.


#3

As Mica suggests, check the NR settings. Screenshot below shows what is there upon opening with Default settings. For what it is worth, I begin RT noise reduction with:
Luma=15
Ldetail=50
Chroma=35
Method=Lab


(Morgan Hardwood) #4

http://rawpedia.rawtherapee.com/The_Image_Editor_Tab#Eek.21_My_Raw_Photo_Looks_Different_than_the_Camera_JPEG


#5

Thanks for the feedback. I also found that by default sharpening was enabled, causing additional visibility of the noisy pattern. Turned off sharpening and enabled noise reduction with the suggested parameters. Results looks much better, similar to the view in the Fuji RAW editor.
Thanks for the feedback.


(Michael) #6

Hallo,
I have big problems with Fuji raf, when the demosaicing in RT. If I use 3-pass, I get many artefactes. If I use Fast, I have less artefactes but it is less sharp. How can I get images with less artefactes?
Thank you.
Micha


(Sebastien Guyader) #7

Can you show examples of such artifacts, and upload one of the problematic RAF files?
I used RT with the Fuji X-T1, and now with the X-T2, and RT doesn’t create more artifacts than others.
Also, start from a neutral processing profile, making sure there’s no strong sharpening turned on.


(Michael) #8

Hallo Sebastien,

the first jpg was made with 3-Pass and no filters.

compared to RT-Fast, no Filters

then RT-3-Pass, Scharpening and NR Filters

and finaly
RT-Fast, Scharpening and NR Filters

Why ist 3-Pass not better than Fast?
The picture was taken with ISO4000 and a Fuji X-T20

Thank you very much


(Ingo Weyrich) #9

Fast x-trans demosaic is prone to artifacts at high contrast edges.
Here’s an example: left is 3-pass, right is fast


(Sebastien Guyader) #10

@micha you uploaded a wrong image, the 2nd and 3rd image are the same. The “RT-fast no filters” image is missing.


(Sebastien Guyader) #11

@micha it looks like the “3-pass sharpening and NR” has more sharpening than its “RT fast” counterpart, or that the latter has no sharpening applied.
Please upload the raw file.


(Michael) #12

here is a new foto, taken with the X-T10 with ISO6400, developped with RT, with 3-Pass and Fast Modus.

First the raf
ISO6400.RAF (32.3 MB)

Then 3-Pass, no filter


Fast, no filter

3-Pass with filters

Fast with filters

to compere: here a detail of the Fuji intern build jpg

and finaly the excellent quality original jpg, made in the body of Fuji.

My question is, who can I make better jpg, then the camera can do (automaitcly)?


(Sebastien Guyader) #13

@heckflosse Ingo, I’m not sure but it looks like Unsharp mask sharpening is not as strong when using Fast demosaicing as it is the using 3-pass algorithm. This may be the reason why @micha sees “artifacts” in sharpened images demaosaiced with the latter.


(Ingo Weyrich) #14

@sguyader Sebastién, If you look at my before/after comparison, which was with neutral profile (only difference was 3-pass vs. fast) you can see that fast leads to a softer image (though with more artifacts at the edges)


(Michael) #15

Hallo Sebastien, hallo Ingo,

as we can see in Ingos example, the 3-Pass might be clearer and sharper, but the artefactes are mor technical, geometric, unorganic and for me more ugly. Do you knows the reason? What is the best preset for Fuji raf?
(May I ask you, where you lives? I live in Germany and I am very glad, that you help me.)
Michael


(Ingo Weyrich) #16

Hello Michael,

I’m from Germany.
Afaik the intention of the 3-pass xtrans demosaic is to get better details, which for noisy images (high ISO) enhances the noise especially if you use sharpening on top.
For low-ISO images, the 3-pass xtrans demosaic almost always gives best results if you avoid too strong sharpening settings.

About the settings, I think @sguyader knows best, as he uses xtrans cameras

Ingo


(Michael) #17

Hallo Ingo,
hoffentlich darf ich Ihnen in Deutsch schreiben. Das fällt mir unendlich viel leichter.
Ihr Bild-Beispiel mit den Bücherrücken zeigt doch sehr schön das Problem, das mir bei RT auffällt:
Der gute Modus: 3-Pass erzeugt diese hässlichen Artefacte, diese waagrechten und senkrechten Pixel-Blöcke. Das sieht sehr unnatürlich aus. Im weicheren, weniger scharfen Modus: Schnell, sind nur halbwegs organisch aussehende, an Filmkorn und Rauschen erinnernde Pixelblöcke. Diese sehen viel organischer und verträglicher aus.
Wie kann man mit RT die Qualität von 3-Pass erreichen, ohne diese Aretefacte?
(Ich finde es super-klasse, dass Ihr mir da “einfach so”, helft. Ich danke Euch sehr.)
Michael


(Ingo Weyrich) #18

Die Artefakte können mit dem Median Filter in der Rauschreduzierung verringert werden.
Das geht etwas zu Lasten der Schärfe, ist aber immer noch schärfer als fast demosaic.

Left: 3-pass without median filter, right: 3-pass with median filter


(Sebastien Guyader) #19

Sometimes, activating False color suppression in the raw tab can suppress some unwanted artifacts.
@micha you said the jpg out of the camera is “excellent”, but I don’t agree. To me the in-camera noise reduction is too aggressive removes some details, and I prefer the look of the RT processed Raw, keeping some noise but also some texture in the fur (which is important in my opinion, for such a subject as the one you photographed).
Here’s what I came up with using RT. It has a bit more luminance noise than in the out-of-camera JPG, but it looks much more natural to me, and I don’t see annoying artifacts (look at the pp3 below if you want to see my settings):


ISO6400.RAF.pp3 (10.2 KB)


(Michael) #20

Hallo Sebastien,
I took your pp3 and the result ist realy good. Yes, the fur has more details with RT.
Is your setting, witch I can see in your pp3 the perfect for Fuji with high ISO? Or is it not possibel to have a optimum setting for a sensor?
What has to be different, when the ISO ist only 1600 and not 6400.
Would it be possible to speek Deutsch with you?
I thank you very much.

Michael