Hello,
I recently acquired PL5 with the 50% Black Friday rebate. I have been interested in trying out the deep prime noise reduction and lens corrections and as this version accepts fuji Raf files, I took the plunge. An interesting option is to export a “linear dng” after denoise and lens corrections but if I understand correctly, before demosaicing.
I tried this but darktable will not read my file…
I tried to include a dng file but the size is too big… how could I share it with you?
Nicolas
A “linear DNG” is usually after demosaicing, and not sure how well that is supported in dt indeed, so you could try exporting as float/16-bit TIFF instead?
DNG 1.5.0.0 adds the concept of enhanced image data, which is a more processed (and always at least demosaiced) version of the raw image data.
Enhanced image data is stored in an IFD with a NewSubFileType of 16 (see section on NewSubFileType for details).
The enhanced image data should always use a PhotometricInterpretation of 34892 (LinearRaw). It should use the same color space as the raw image data.
The LinearRaw PhotometricInterpretation value is intended for use by cameras that do not use color filter arrays, but instead capture all color components at each pixel. It can also be used for CFA data that has already been de-mosaiced.
Instead of the DNG file, you can start w/ sharing the output of exiftool -a -u -s -g1 so we can try figure out what we’re dealing with (could be large as well, so as an attachment would be better).
Thanks,
I would like to have an un-demosaiced file from PL5 but I don’t really know what it is giving me…
exiftool output.txt (11.8 KB)
No problem with PureRAW and linear dng from Canon CR2 in darktable.
You’re definitely getting the 16-bit image after demosaicing (3 samples per pixel, i.e. RGB):
---- SubIFD ----
SubfileType : Full-resolution image
ImageWidth : 6240
ImageHeight : 4160
BitsPerSample : 16 16 16
Compression : JPEG
PhotometricInterpretation : Linear Raw
SamplesPerPixel : 3
P.S. Don’t be fooled by “JPEG”, it designates lossless JPEG SOF3 compression.
Support for this option in dt is indeed basic and depends on other implementation details (please share a file over some cloud service if possible for further study). Can you export as TIFF instead, or try to turn compression off for DNG export?
Funny thing really, if I open directly from the lightable, darktable refuses to open the file but if I open from photomechanic (edit with darktable), it opens the dng !
Here are the links to the original raw and the dng
https://drive.google.com/file/d/1P4xH48UXzqXXtD26IhuCJfO48dBWoINX/view?usp=sharing
https://drive.google.com/file/d/12b2inmYLJEMuVkpI-ySx61T2CBHUwe87/view?usp=sharing
Thanks for taking the time!
Btw, I have no problem opening it in the latest development build, so you could just wait a bit… 
I have the latest development build !
There is quite a bit of discussion on this thread from which one comment states…
Again, as I understand it, I am afraid you have it the wrong way round. A linear demosaiced DNG file such as that produced from DXO or a LR pano is basically a Tif file that does not have a white point applied and therefore when you open the file in different raw converters they apply their own default interpretation. Therefore if you want to keep the colour you produce in for example DXO in another application export as a Tif.
@priort Not the issue being discussed here… (yet?)
@nwinspeare I’m stumped then… You built w/ rawspeed sub-module updated as well? Any hints in the log if you run as darktable -d all? Last resort of course, is to do a debug build and start it in a debugger…
Sorry I thought it was still to be confirmed as to the demosaic’d status…I can confirm that running windows both files open fine that you provided @nwinspeare . I would try just deleting you build directory and starting with a new one… Whenever and it has been rare I have this sort of issue that is the first thing that I try…works most times…
I use the dng files from pl5 (and 4, and 3, and dxo optics pro, … ) with darktable all the time.
I had no issues with opening them, so it might be camera related.
Linear dng files are after demosaicing, but before things like white balance multipliers , camera profile and any tone curves.
And of course some modules could be enabled in pl5 to alter the data even more before hitting darktable. Like lens corrections , sharpening , chromatic aberrations, defringing , denoising … Even cropping, rotating, perspective …
And yes, you can alter the color data like exposure and their dehazing etc … but no clue how darktable is going to respond to it.
Thanks everyone, I have the answers I need : the file is demosaiced so that is that.
I can open it in a fashion with darktable… I’m sure that will be fixed in a later build. I’m using the ones kindly provided on this thread current OSX Build - #379 by ricochet
I’ll use the dxo dng file for denoising if I find that darktable has trouble with very high iso files. At least I can use the color calibration module as I prefer the color rendering on darktable.
Cheers,
Nicolas