Help importing DNG files

I am using PureRAW 3 in my workflow, trying to import DNG files that were exported via Lightroom or via the Adobe DNG converter (i tried both), but in the app it only shows a full white square, and after export it is a full white square.

Now a bit about these files, they are from 5D2 shot using Dual-ISO feature that gives about 2.5-3 stops more of dynamic range, but requires processing in the form of conversion with a tool “cr2hdr” to create completed DNG files.
These DNG files are read fine and edited fine in all apps i have on my computer, but not Pure Raw (and i didnt expect it because it is stated). But i assumed that if i then exported these DNGs into DNG using lightroom, lightroom would apply its “correct” encoding and then it would work, but it doesnt seem to be the case. I do not have any compression or anything else enabled, comparibility profile is Camera raw 14.0
Does anyone know any hacks how to take a normal (but PR3 unsupported) DNG and convert it into supported DNG?
Thank you, best regards

DxO are pretty clear on the fact that DNG files must be from a supported camera/lens combo, either natively or via Adobe conversion. What you have is a file with a “special mode” which will not be supported by DxO.

I have a Pentax KP which has “Pixel Shift” capability and that is not supported no matter what format file it is in. I’m sure I’ve seen others in the forums talk about special modes on their cameras also not being supported.

The short answer is anything other than a single Bayer/Foveon matrix capture is not going to be supported.

This is a regular bayer capture, in fact i can process the .cr2’s out of the camera normally with DXO, but then the images are useless because they are subtly changed and cant be turned back into normal images by cr2hdr.
One of the things it does to have a useful and not “stripey” image is it debayers it, creating Linear DNG’s.

The real issue thus is that Linear DNG’s are not supported, meaning they have some processing (like demoisaicing) applied which PureRaw does not like.
So original post could be reworded to, is there a hack or method to repackage Linear DNG’s for PureRAW to be able to recognise them…

I should clarify my point about the “single Bayer/Foveon matrix”. You mentioned your camera’s “Dual-ISO feature” which I take to mean there is more information in the file than just a single captured frame.

In the case of my Pentax Pixel Shift, there is a completely different matrix in the file as it combines four captures into a single fully-RGB matrix. I would assume “Dual-ISO” is a multi-frame capture where each frame is at a different ISO.

The key thing to understand is the basic concept of a RAW file is a dump of the sensor data once. PureRAW and PhotoLab read that single dump from supported cameras and lenses. If the basic RAW file is not supported, there may be tricks you can use (principally faking the metadata to represent a supported device) to force them to open, but any special treatment, whether in-camera or after the fact, will generally render it un-openable. The only post-processing PureRAW/PhotoLab will tolerate is conversion from native RAW to native DNG and that only if done with Adobe DNG Converter (which is also built into Lightroom).

I see, this is a bit of a different thing and more of a “firmware hack” if you will. It just forces the camera’s ADC registers to sample each alternate line in a different ISO value, so its still a regular single image capture, the benefits being you require no tripod, no exact framing for several consecutive frames etc, just shoot normally. Otherwise you might as well just bracket a few exposures and stitch in post for an even greater DR improvement. The image is encoded normally by the camera and is fully supported by PR3. It can then be recovered by running it through the aformentioned program (cr2hdr) into something normal looking. Its not a very user friendly or “polished” feature per-se, but pulls a lot more out of your 2008 camera. Heck, even 550D’s you can get on ebay for about 100$ have about 13 stops of DR and shoot 14bit RAW with c-log and many other things with this firmware. It is really interesting what they managed over the years.

Anyway not to digress too much, the basic RAW file is indeed supported, even this “hack-y” one because it is esentially still the same old .CR2 from Canons, just with alternating ISO’s, so its not really a matter of metadata or original file not supported. The problem is if i run it first through PureRAW then its later unusuable because i cant recover it into a normal looking (and not stripey) image through cr2hdr, as it has been altered, and if i first run it through cr2hdr then i cant run it through PureRAW at all because the aformentioned program has a ““temporary debayering”” step, making it a Linear DNG which PureRAW doesnt support. Thus i am at an impasse! So i suppose i have to choose one or the other. And PureRAW really has a subtle but effective effect, unlike any other AI tool i’ve tried previously. They keep everything natural about an image and just make it cleaner and clearer.

OK, that makes sense. And I kind of have the same answer…

PureRAW wants the original RAW, which it technically has, but so does cr2hdr. You can choose to use one or the other. As soon as you run it through one, you no longer have “an original” to give the other.

1 Like

Hello, yes that is precisely so! :slight_smile: