Is there a list of the EXIF data that DxO PL uses to develop the RAW image

When I set my camera Picture control = Monochrome (Nokin D7500) to get a black and white photo, I noticed that DxO PL converts my RAW image to color.
This may be normal because “Picture Control” is camera specific.
When I play with the while balance, I see that DxO PL understands the WB EXIF data and show my RAW image based on the chosen WB.
Question is there a list of EXIF data that DxO understands and interprets, thanks.

Daniel Kuppens
dankup@gmail.com

Actually, when you use the Picture Controls, they are only ever applied to the preview jpeg file that lives inside the RAW file, or the external jpeg if you shoot in RAW+jpeg.

PL doesn’t convert your image into colour; the RAW image is always in colour because it is, simply put, the raw data that the sensor saw when you took the picture.

How the camera got to a black and white jpeg is not recorded in the EXIF and, because a jpeg file is much more limited in what it records (8 bits), has no relevance to how a full (14 bits) RAW file should look.

I have a Nikon D810 and always keep my picture control on flat, so that the jpeg image I see on the back of the camera isn’t influenced by anything. I don’t find that having this preview image in B&W is really much good because of its limited range and quality.

Here, I have extracted the inner jpeg from one of my files

And here is an export of the RAW file after it has been treated in PL to make a B&W image

There seems to be no such list.

My guess is that the following items will influence the outcome:

  • Camera model
  • Lens model
  • Distance
  • Focal length
  • Aperture
  • Shutter speed
  • ISO
  • WB
  • ?

We could try to map these items to DPL’s tools, but doing it in a one-dimensional text tool would certainly not be my first choice and I’ rather use DPL than to reverse engineer its way of working :wink:

Morever, I think that knowing what camera settings help to get technically good shots is more important.

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I understand what Joanna explained but I think what Daniel indirectly suggested could still make sense: Of course the RAW file will always be in colour, but if the RAW file contains the info that it should be developed into B&W this “instruction” could be used by PL to automatically set the development settings to B&W. The outcome of course will be different compared to the out-of-camera B&W jpeg but that’s always the case wit any picture - that’s why we use software like PL.

Let me give you an example with something I experienced a few years ago when I was still using Lightroom. I shot RAW but applied a crop factor in camera. When I first opened the RAW file in LR it “suggested” to crop the image as set in camera. However the RAW file of course included the full and uncropped raw data of the picture so I could still decide to crop differently in LR.

Taking this example back to the B&W idea, even if the B&W preset is correctly interpreted by PL, the user should still be able to override this preset and switch back to colour, even thoughthe out of camera development preset would be B&W.

Hi Daniel,
that’s an interesting question. But if you want to make use of your camera’s picture control settings, you will have to develop the raw-files with proprietary Nikon software solely.

On location with plenty of time (no people or concert photography) I might set WB or B&W creatively to ‘see’ what works, as well as to have an idea for post.
have fun, Wolfgang

To return to your original post :

The answer is, only the basic exposure and operational data. The Picture Control stuff is proprietary and, unless you use Nikon’s own software, is only used in the camera to construct a jpeg to show on the back of the camera or if you want to create RAW/jpeg pairs.

The basic advice is, if you want to work with RAW files, ignore the Picture Controls.

Thanks all for your replies and feedback.
I understand all that, i understand that RAW is color, I understand that there are general and camera specefic setups and exif data
I just wonder if there is clear list of Exif attributes used by DxO to develop the RAW file.

The list of Exif attributes would be quite long and will likely differ by camera brand/model. This is particularly true for so-called ‘maker notes’ that manufacturers use to hide detailed information about camera model, lens data, etc., etc. PhotoLab uses some of this Exif data for functions like lens corrections, noise reduction, etc., in addition to using more common data like lens aperture, shutter speed, ISO, etc. As a side note, if some of this Exif data is corrupted by an external programs, it make prevent PhotoLab from recognizing the image properly (I’ve had this happen in the past in a few situations; fortunately this problem is fairly rare these days).

i understand that RAW is color

No, RAW is just the data off the sensor. In fact RAW is not even a picture. RAW only becomes something a computer understands as a picture (JPEG/TIFF/whatever) after it has been through a RAW converter like PL (or LR, or PS, or [insert name])

stuck

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To bemore exact a rgb raster image. Jpeg/tiff etc are disk files that store that image in a certain way.

@Dankup,
See it somewhat different. In the camera’s software there is a raw converter too.That is used to demosaic the raw data just like pl,lr or any other converter… Picture Controle are just edits that are used during that process, something like presets in pl.

George

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@stuck @George : I agree and I fully understand your feedback.

@jch2103: Thanks for your reply, so there is no documented list of exif attributes used by dxo to demosiac and develop the raw data.

I’m not aware of a publically available list. Of course, DxO has internal lists that they use. I expect they consider that to be proprietary information.

indeed, there is no list, nevertheless, some relations can be established.

In order for DPL to correct something automatically, exif tags are read and taken into account. Camera and lens model info is use to select the “lens” module, add focal length and distance info for distortion correction, add aperture for vignetting and CA correction etc.etc.

Ask yourself “what info is needed for a correction?” and you can start to draw a map of relations.

Sometimes, focal length and distance (just an example) are not set (new lens on old body) and then you can influence distortion correction (etc.) by using the sliders in the FL and Dist. tools.

Explore the tools and start drawing the map. Share it if you think you got it.
Or simply enjoy the things you can do with DPL.

I’m not a metadata expert, but I can say that basically you have two types of EXIF data: ‘universal data’ and ‘unique data’. For universal I mean shoot date, iso, aperture, camera body, rating and so on…

By ‘unique data’ I mean proprietary corrections for instance that are applied to the generated in-camera JPG (even if you shoot RAW only, JPG are created to give a preview of the shoot on the LCD screen…). Proprietary corrections are made by each brand following their own ‘standards’, they do not have any common ‘way of doing’ with third party solutions…Even converting an image to B&W, seems trivial, but it’s not.

There is not a ‘universal method’ for that, unless all camera brands and software decide to adopt one (like simply desaturate the image)…It’s like with LR, C1 or PL: they all do the same thing, but with their own standards and algorithms: you just can’t import a C1 RAW image keeping all its corrections (and final output result) in LR or PL and vice-versa…

Having said that, we could have an ‘in the middle solution’, as suggested above, with just PL ‘switching your image to B&W’ without trying to match the in-camera proprietary style…As a user I understand the need for a faster workflow, but in this case for instance it would be more practical to import my RAWs with a B&W preset applied by default, no?

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Hi Steven, thank you to chime in.
When developing my pics with LR 5, I used to switch to B&W quite regularly just to have an idea
about the ‘graphics’ and when pleasing, I would continue with PS / NIK Silver Efex.
In a way, that’s about the same as using the (general) B&W preset in PL. So, from there one could continue either way.
regards, Wolfgang

Yes, if we can read that a (proprietary) ‘in camera picture style’ has set an image to “B&W”, we could apply a basic B&W preset in PL…to let you start editing with…

Unfortunately, it’s even worse than that: some of the ‘universal data’ is recorded by different manufacturers (and even different camera models from the same manufacturer!) in proprietary and sometimes encrypted Exif tags. The excellent ExifTool folks have deciphered many of these tags, but many others are unknown by anyone except the manufacturer. There are currently some 15,000 or more photo-related metadata tags!

This situation is unlikely to change as long as equipment makers think they have a proprietary advantage in keeping this kind of information hidden/secret. It means folks like DxO and even Adobe (let alone end users who just want to develop their RAW images in different ways or use different camera/lens combinations, etc.) have to reverse engineer image files from each camera/lens; or use a product like ExifTool; or make special arrangements with the manufacturer. Life would be a lot simpler (and less expensive) if they agreed to common data standards, but this doesn’t seem at all likely…

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Thanks you all for your feedback, seems like an interesting discussion.
So when I put my DxO PL preferences for RAW images to “No correction” DxO PL demosaic the RAW sensor data, ignores the embedded JPEG and ignores the camera specef Exif (like many other RAW convertors except the Camera spececif RAW convertors).
And as such my B/W image results in a color image…
The camera B/W setting (and many others) are not interpreted by most RAW convertor.

Strictly, your image was never B&W or, at least, the RAW image. Only the embedded jpeg gets processed, in camera, to the B&W Picture Control settings

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No Correction simply means that DPL will calculate a preview with parameters that DxO deem best.

Every raw converter does the same: Projects an image with converter specific parameters that more or less aim to emulate what the camera would show. Some converters can emulate camera specific picture styles too, others can’t or don’t.

There is one way (that I use) to make DPL consider camera specific styles: Use .dcp (or .icc) profiles that other converters provide. Still, DPL can’t select such profiles automatically and based on a file’s exif data.