It may make sense after all.

Geeqie (most certainly) and Nikon (very probably) report the definition of the JPEG file embedded in the RAW, which is the actual output of the Nikon processing algorithm.

This would be similar to what I observe on the D5200, where the RAW and JPEG have different definitions (sidecar JPEG and embedded JPEG are both 6000x4000). Viewing both images and looking for possible crop and/or resize allows to actually notice the lens correction processing by Nikon. The point might have been to crop the picture so that most of the time, we have both 1:1 pixel coverage in the center while avoiding black areas on the side and corners due to lens correction.

Using ufraw-batch --embedded to extract the embedded JPG from a D5200 RAW file indeed produces a 6000x4000 JPEG.

Interestingly, darktable report the NEF is 6016x4016 while ufraw reports 6078x4058. This is becoming stranger.

Anyway, D5200 has only one RAW definition.

Perhaps the embedded JPEG size is really much smaller when using reduced RAWs, because, you know, the point is the camera user asked to save storage space and, since they have the raw file they're supposed to have means to regenerate a JPEG from that.


Can you try the commands below for each raw and sidecar-jpeg files?

identify mypicture.JPG
ufraw-batch --embedded mypicture.NEF ; identify mypicture.embedded.jpg
ufraw-batch --out-type=jpg --output=mypicture.ufrawprocessed.jpg mypicture.NEF ; identify mypicture.ufrawprocessed.jpg




Le 12/01/2019 à 23.58, Bernhard a écrit :
it looks like the RAW files published here https://raw.pixls.us/ show the same deviation - and the exifdata show the same values like darktable.
I still do not understand why Geeqie and Nikon report other numbers ...

Bernhard schrieb am 11.01.19 um 14:27:
Nikon enables the use of RAW files of different sizes in the D850. According to the specifications in the manual, the formats are defined as follows:
L 8256 × 5504
M 6192 × 4128
S 4128 × 2752
(these figures are also shown in the camera menu)

darktable tells me:
L 8288 x 5520
M 7104 x 4728
S 6216 x 4136

While the deviations for size L are still small (we had a discussion about them in the past), they are very significant for M and L - according to Nikon a file of size S 11.3MP, while darktable assumes over 25MP.
Geeqie again shows the Nikon numbers.
Exiftool shows the darktable numbers.

A jpg or tiff file exported from darktable shows the darktable numbers in xnview.

What is going on here?



--
Stéphane Gourichon

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