Q2 raw file has corner blocked?

[Jiang]

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I found today suddenly, the raw DNG file have 4 corners blocked.  refer to screen shot below. 

I just got this Q2 2 weeks ago, and I did not check raw file before, I found all raw file have this issue from first day in my hand when I set output raw.

The jpeg file seems simply is cropped from long side of the image.  

The problem remains even without the hood and UV filter. 

I checked raw file of another camera (GR IIIx), no such issue. 

Is this normal??  

my camera firmware version is 4.0

Thank you. 

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Edited August 21, 2022 by Jiang

[jaapv]

You are seeing the. uncorrected file. The Q series lens is a hybrid design, corrected both optically and digitally. (like many high-end lenses nowadays) The optical design shifts some aberrations - lens design is basically about shifting and compensating aberrations - into distortion towards the corners and then corrects the result digitally, reducing distortion and cropping the 24 mm lens down to 28 mm FOV. The parameters are stored with the DNG in a sidecar file.
This whole process makes the lens better and more compact than a purely optical design could be and is particularly suited to the Q. with its integrated lens-sensor unit.
Somehow this sidecar file was not read in postprocessing - look at your raw converter settings.

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[Anbaric]

1 hour ago, Jiang said:

I found today suddenly, the raw DNG file have 4 corners blocked.  refer to screen shot below.

Which raw converter/viewer are you using? You may want to check if it has (and is using) a specific profile for the Q2 and is set to apply appropriate lens corrections.

[Jiang]

14 minutes ago, Anbaric said:

Which raw converter/viewer are you using? You may want to check if it has (and is using) a specific profile for the Q2 and is set to apply appropriate lens corrections.

I tried 2 free raw file converters,  Darktable and RawTherapee, both seeing same vegnetting.

[Jiang]

2 hours ago, jaapv said:

You are seeing the. uncorrected file. The Q series lens is a hybrid design, corrected both optically and digitally. (like. many high-end lenses nowadays) The optical design shifts some aberrations -lens design is basically about shifting and compensating aberrations- into distortion towards the corners and then corrects the result digitally, reducing distortion and cropping the 24 mm lens down to 28 mm FOV. The parameters are stored with the DNG in a sidecar file.
This whole process makes the lens better and more compact than a purely optical design couls be and is particularly suited to the Q. with its integrated lens-sensor unit.
Somehow this sidecar file was not read in postprocessing - look at your raw converter settings.

thank you jaapv! glad to know this is normal. Is there official document from Leica, or other department, to confirm such heavy vegnetting is normal on original raw file? 

[Viv]

Your processor is not correcting the file. This happens, for example, with Photoninja.

You have two choices. Crop out the corners, or use a different processor.

[Anbaric]

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1 hour ago, Jiang said:

I tried 2 free raw file converters,  Darktable and RawTherapee, both seeing same vegnetting.

I believe these both use the Lensfun database for lens corrections, which currently doesn't seem to include vignetting correction for the Q2:

https://wilson.bronger.org/lensfun_coverage.html

https://lensfun.github.io/

https://rawpedia.rawtherapee.com/Lens/Geometry#Lensfun

https://docs.darktable.org/usermanual/3.8/en/module-reference/processing-modules/lens-correction/

You may want to try the demo versions of some of the major commercial raw processors to see how they handle these files, though several of these also use Lensfun and may have the same issue unless they have dealt with it in some other way (like using the metadata in the DNG in the way Leica intends):

http://lensfun.sourceforge.net/usage/

Maybe Capture One, DxO or Lightroom, which I think do their own corrections? Of course, Lightroom is only available as a subscription.

Unlike most other manufacturers, Leica unfortunately don't provide a free basic raw converter tuned to their files - they should really do a deal with Silkypix or Capture One, like Nikon, Sony and Fuji have.

Edited August 21, 2022 by Anbaric

[jaapv]

There are plenty of (free) mainstream raw converters that do apply the lens corrections. The outliers sometimes don’t. 

[Anbaric]

41 minutes ago, jaapv said:

There are plenty of (free) mainstream raw converters that do apply the lens corrections. The outliers sometimes don’t. 

Which ones work well with the Q2?

Edit: Fiddling with a random Q2 file in Affinity Photo (a commercial package that uses Lensfun), I find I get vignetting by default but, while there is no lens profile labelled 'Q2', there is one called 'Leica 28.0mm f/1.7', which deals with the vignetting if I apply it manually. So it's worth exploring the settings of whatever converter you have to see if there's anything that fixes this. My old copy of CS6/ACR, incidentally, deals with the Q2 file correctly and automatically, presumably using the DNG metadata.

Edited August 21, 2022 by Anbaric

[Anbaric]

Exploring a little more, I see that the current version of RawTherapee has a 'Profiled Lens Correction' menu. If I choose 'Manually selected' and set the Camera as 'Leica Q (Typ 116)' and the Lens as 'Leica Camera AG 28.0mm f/1.7', then the vignetting correction is applied, though whether the lens correction is accurate for the Q2 is another matter (there doesn't seem to be an entry for the Q2 in this build of RT).

[Jiang]

29 minutes ago, Anbaric said:

Exploring a little more, I see that the current version of RawTherapee has a 'Profiled Lens Correction' menu. If I choose 'Manually selected' and set the Camera as 'Leica Q (Typ 116)' and the Lens as 'Leica Camera AG 28.0mm f/1.7', then the vignetting correction is applied, though whether the lens correction is accurate for the Q2 is another matter (there doesn't seem to be an entry for the Q2 in this build of RT).

yes, it works!  Many thanks Anbaric!

[SrMi]

5 hours ago, jaapv said:

You are seeing the. uncorrected file. The Q series lens is a hybrid design, corrected both optically and digitally. (like. many high-end lenses nowadays) The optical design shifts some aberrations -lens design is basically about shifting and compensating aberrations- into distortion towards the corners and then corrects the result digitally, reducing distortion and cropping the 24 mm lens down to 28 mm FOV. The parameters are stored with the DNG in a sidecar file.
This whole process makes the lens better and more compact than a purely optical design couls be and is particularly suited to the Q. with its integrated lens-sensor unit.
Somehow this sidecar file was not read in postprocessing - look at your raw converter settings.

+1

The distortion correction parameters are stored in the WarpRectilinear Opcode inside the DNG. There is no sidecar (XMP) file, unless it is generated by Adobe.

Some software is not decoding the Opcodes correctly, some use their own distortion correction data (e.g., DxO).

[Jiang]

Found another thread of 2 years ago, of exact the same finding on Q2. 🙂

 

 

[Farrell Gallery]

It's possibly the bayonet lens hood on crooked blocking part of the frame corner. . I got rid of the factory hood and cap, that hasn't happened to me since. I had to crank it to never never land to get it close to straight. 

Edited August 22, 2022 by Farrell Gallery

[Jiang]

1 hour ago, Farrell Gallery said:

It's possibly the bayonet lens hood on crooked blocking part of the frame corner. . I got rid of the factory hood and cap, that hasn't happened to me since. I had to crank it to never never land to get it close to straight. 

Ya.. this lens hood is a bit hard to screw all the way to correct location. 

the original vignetting on uncorrected picture still there without lens hood. 

Edited August 22, 2022 by Jiang

[Farrell Gallery]

On 8/21/2022 at 10:32 PM, Jiang said:

Ya.. this lens hood is a bit hard to screw all the way to correct location. 

the original vignetting on uncorrected picture still there without lens hood. 

Well dang, it was worth a thought anyhow...let us know any developments. 

[SrMi]

4 hours ago, Farrell Gallery said:

Well dang, it was worth a thought anyhow...let us know any developments. 

I thought the issue was addressed: @Jiangwas looking at the uncorrected DNG. 

[Jiang]

On 8/26/2022 at 7:59 PM, Farrell Gallery said:

Well dang, it was worth a thought anyhow...let us know any developments. 

Just screw all the way, you will know when the hood reach correct position.

[Jiang]

On 8/27/2022 at 12:39 AM, SrMi said:

I thought the issue was addressed: @Jiangwas looking at the uncorrected DNG. 

Yes. Thank you SrMi.

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Hallo,

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[tuxfan1]

Correction data for distortion and tca are included in the Lensfun database for the Q2, see here and here (line 108). How the data for the lens correction can be generated is described here and here. If the generation of the data with the software tools is too complicated or not possible, you can hand over the necessary raw images for profile generation to the Lensfun project here.