P: Save JPG as DNG breaks maker notes

[Hayo_Baan]

When saving a file that was originally a JPG to a DNG file, the camera maker notes are written incorrectly and have become corrupted.

Together with Phil Harvey (author of exiftool) I analysed the issue and we found that the makernotes are copied from an area in the original file that is off by 12 bytes; the maker note data is prefixed with 12 bytes (from other metadata tags) and the final 12 bytes are missing. This is problematic as my workflow uses information from the makernotes…

The problem has been around for a while and is still present in the latest verion of camera raw (14.3).

If you need, I can provide example files.

Hope you can fix this soon,
Hayo Baan

[TheDigitalDog]

Gotta ask: Why would you save a JPEG inside the DNG container? 

[Hayo_Baan]

Because then I can edit the JPG and treat the JPG as if it where a RAW file with all advantages that brings me (single file, non-destructive editing, etc.). Sure I could have saved it as a TIFF with a smart object, but my whole workflow is centered around (dng) raw files, so this is more convenient to me 😉

[TheDigitalDog]

No, you can't. It's just a JPEG inside the DNG container, it isn't any more 'raw' and of course, you could just continue parametric edits of the JPEG in either LR or ACR. Both products allow editing of the JPEG this way without any need to 'convert' (which is simply embedding) the JPEG into that container. 

Embedding a JPEG into a DNG isn't doing anything useful; it is still a JPEG. 

[Hayo_Baan]

YES, I understand that, of course.

But for my whole worflow it is critical the preview in the file is what the end result will look like.

With a JPG (or non-DNG raw files) and separated edits that just isn't the case. With the DNG you can have the embedded preview reflect the end result. This allows me to browse with other software (I use PhotoMechanic for instance, but also the Finder then shown me the result of the edits) and see what the final image will look like. This is VERY important to me.

[TheDigitalDog]

Using a JPEG in ACR/LR will preview the file as the end results will appear. 

Yeah, outside, it will not. Because you haven't rendered the edits. 

But if you are clear that you are not treating the JPG as if it were a RAW raw file, fine. Some incorrectly believe that embedding a TIFF or JPEG into DNG makes it raw, seems we both agree, it doesn't. 

[Hayo_Baan]

Indeed we fully agree: it doesn't make it a real raw. It's still the same source data, just in a container (allowing you to combine it in one file with the parametric edits and a rendered preview, but it won't make the source data any different).

[Hayo_Baan]

Why was this moved from BUGS to DISCUSSIONS? This IS a bug!

[TheDigitalDog]

I didn't move it. 

[Hayo_Baan]

I didn't think you did, but it was moved nonetheless, hence my question...

[Hayo_Baan]

When saving a file that was originally a JPG to a DNG file, the camera maker notes are written incorrectly and have become corrupted.

Together with Phil Harvey (author of exiftool) I analysed the issue and we found that the makernotes are copied from an area in the original file that is off by 12 bytes; the maker note data is prefixed with 12 bytes (from other metadata tags) and the final 12 bytes are missing. This is problematic as my workflow uses information from the makernotes…

The problem has been around for a while and is still present in the latest verion of camera raw (14.3).

If you need, I can provide example files.

Hope you can fix this soon,
Hayo Baan

P.S. This is a repost as my original post inadvertently got moved to “Discussions” but it is definitely a bug.

[Rikk Flohr: Photography]

Greetings,

The Camera Raw team would like to obtain a sample JPEG file and DNG that exhibit the problem, can you supply a set of files for us to review?

[Hayo_Baan]

Hi Rikk, sure I can. But actually any JPG with makernote data saved as DNG will do (e.g. from an iPhone).
I've uploaded  a sample (both the JPG and the DNG) as well: https://we.tl/t-6zLOI7zGfK

[Rikk Flohr: Photography]

Setting status to investigating
Adding bug number 

[Rikk Flohr: Photography]

Greetings,

Updates to the Adobe Photography Products were released on June 13. The update contains a fix for this issue.  Please download and the latest version of your application via the Adobe Creative Cloud Application or your respective device app store.

If you do not see the update (Mac and Win) you can refresh your Creative Cloud App with the keyboard shortcut [Ctrl/Cmd]+[Alt/Opt]+[ R ]. 

Note: App store availability can take several days for the update to appear and be available. 

Thank you for your patience.

[Hayo_Baan]

Excellent: problem appears to be fixed!

Thanks 😀