Support for ILCE-7CM2

Hi All,

Just wanted to ask - ILCE-7CM2 is a brand new camera. Technically - there are no samples on raw.pixls.us
However - it uses the same sensor as ILCE-7M4/ILCE-7M4K
I understand an FR for camera support in darktable is expected to be accompanied with RAW files.
To my surprise - rawtherapee was able to open and edit ILCE-7CM2 even during the initial review of the camera. Samples on dpreview Sony a7Cm2 Overview: Digital Photography Review

I am pleasantly surprised of course that rawtherapee can handle it but how does it does it do it? Is it based on assumption and see what will happen? I would like to see it supported in darktable too but I guess I will have to wait until somebody submits samples (and no - I don’t have the camera - otherwise there would have been samples).

For Sony darktable uses Rawspeed. In Rawspeed you have the file cameras.xml. There you have how much of the image that should be cropped, black level, white level, colour matrix etc.

Take a backup of your local cameras.xml. The simple way is to edit it and just replace the old camera model with the new camera model name. Now you lose support for the old model but gain support for the new.

The better way is to create a new camera post and add the new model. Colour matrix is extracted from dng files converted from Adobe DNG Converter.

Even if the sensor is the same it may still be configured different like more crop or a different colour matrix. We will know if the colour matrix is the same when Adobe DNG Converter supports the new camera.

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I uploaded a few samples for the ILCE-7CM2 the other day, but they are yet to appear in the repo.

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Welcome, and thanks for the samples! They undergo a manual approval process by @LebedevRI

Unless someone already made some changes to model aliases in dev builds (don’t recall seeing something about that), it’s likely opening without any appropriate color calibration information (color matrix, etc.)

I haven’t used RT’s model alias functionality yet, an alternative method is to take the ILCE-7M4 DCP and copy/rename it so it matches for the 7CM2.

Note that lossless compressed ARW is not yet supported, only uncompressed and lossy compressed.

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Yeah, it could be falling through to a substring of e.g. existing 7C, like LibRaw would do… You think it’s supported, but you don’t know what input profile you’re getting. Not ideal.

Thank you for the contribution!
Verified 5-sample set.

It would be great to have the APS-C lossless one as well…

Did you buy it? How is the experience? I haven’t seen it yet in real life - just on the web.

I will upload one.

There’s also 3 different modes of lossless compression available (S, M, and L), I’m not sure if all of these are interesting.

And I know 12 bit samples are wanted, but I haven’t found a way to switch the output to 12 bit.

Yes I bought it, and I like it. I don’t have loads to compare it to, I used an A7ii before and I like the compact size, and the smaller viewfinder doesn’t bother me.

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Thanks. We just need the APS-C lossless (which AFAICT is kind of “M” when in APS-C crop mode) for now. The M & S in FF mode are not really raws and not currently supported by darktable/rawspeed anyway, but you’re welcome to upload them!

I am happy for you!

I think it would be optimal to have the exhaustive sample set at least for the basic no-crop mode.
It would be awesome if you could append the _{compression?}(_crop?) suffix to filenames,
so it’s more obvious what is what.

IIRC previously that happened in bulb (or high-shutter-speed?) mode.

Many Sony cameras have both 12 and 14 bit images

ILCE-7CM2 is not on the list
But the closest one from the article above are

ILCE-7M4 / ILCE-7RM5

  • Shutter Type: Mechanical Shut
Setting Single-shot shooting*1 Continuous shooting*2 BULB shooting Long Exposure NR is activated *****3
Compressed RAW 14-bit 12-bit 14-bit 14-bit
Lossless compressed RAW 14-bit 14-bit 14-bit 14-bit
Uncompressed RAW 14-bit 14-bit 14-bit 14-bit
  • Shutter Type: Electronic Shut or Silent mode: On
Setting Single-shot shooting*1 *Continuous shooting 2
Compressed RAW 14-bit 12-bit
Lossless compressed RAW 14-bit 14-bit
Uncompressed RAW 14-bit 14-bit

When I am to cross check to the manual
https://helpguide.sony.net/ilc/2360/v1/en/contents/0404M_file_format.html?search=14%20bit

it says that all images are in 14 bit

About RAW images

  • To open a RAW image file recorded with this camera, the software Imaging Edge Desktop is needed. With Imaging Edge Desktop, you can open a RAW image file, then convert it into a popular image format such as JPEG or TIFF, or readjust the white balance, saturation or contrast of the image.
  • RAW images recorded with this camera have a resolution of 14 bits per pixel.
  • You can set the compression format for RAW images using [RAW File Type].

However - I don’t know how to verify if the image is 12 or 14 bit by having a RAW.

Okay, maybe that camera indeed does not produce 12-bit images.
That information should be in the EXIF data,
i’d suggest running exiv2 / exiftool and looking at BitsPerSample tags,
or comparing the whole output between known-14-bit images,
and the suspect image.

I have verified all the files that I took (and I also provided at https://raw.pixls.us/)
The only file that reported 12 bit is the lossy compression. The rest were 14. Including the bulb.

The M and S reported
Bits Per Sample : 15 15 15

@sams96 already provided better files than me but if you need some of the ones I uploaded at least they are there. And whatever is not needed you can discard. I did label them as much as I could.

If there is anything specific needed in term of files (that is lacking) please let me know.

M and S are not raw files per se, they’re demosaiced and converted to luma/chroma:

Exif.SubImage1.PhotometricInterpretation      YCbCr
Exif.SubImage1.SamplesPerPixel                3

I don’t use them actually. I did try Canon 70D with M shooting about 9 years ago. DT did process them at the time but looks like Sony maybe a different thing.

I suspect very similar, just not implemented for Sony yet.