The bug report serves to attract some attention from DxO. They strive for better quality and might want to find out why their algorithm darkens the image.
As far as I remember, PR also applies smart lighting, although it is not mentioned in the manual.
I tried to reproduce the looks of the preview, and found that, starting from a PR dng file, it was not trivial… Other than that, an intermediate file should not be used as a reference, be it an ooc preview or a PR dng. Nevertheless, PR also offers to export as JPEG, something that is not suited well for postprocessing and that should therefore have usable qualities, which I don’t find in the case of the swamphen image.
platypus
yes, I will asking solution to DxO .
below image from DPP and PhotoShop Camera RAW , all looks normal , Camera RAW even brighter than DPP , but such a tiny difference
is OK to me .
The point is that, from what I can understand, PR takes the unmodified RAW image, applies lens corrections and noise reduction and then exports it to DNG without any other adjustments.
A jpeg preview of what you see in DPP is already processed to make it look like the embedded jpeg.
Since the DNG that is exported from PR is purely the unadjusted RAW, it is hardly surprising that it looks exactly the same as the unadjusted RAW you see in PL4.
It is futile to compare the DNG from PR with either an adjusted version of the the RAW that you see I DPP because DPP has a already applied changes to try and match it to the embedded jpeg.
Try opening the CR2 files in PL4, do nothing to them, don’t even apply the standard preset which changes things and then export it straightaway to DNG. You will get a dark image that matches the unadjusted RAW you see in PL4.
But, I will repeat, PR does not apply any adjustments and only exports the essential RAW image, which, only rarely matches the jpeg preview. This is not a bug in PR. It is exactly what PL4 does if you don’t apply any adjustments.
From the manual Exporting to an application DxO PureRAW does not have any image correction and processing tools, as its role is to produce a linear DNG file with perfectly-treated noise and lens flaws. It is an independent program, not a plugin. However, you can open linear DNG files in any photo program that supports this format.
Leaves the question: what is a linear DNG file exactly.
That’s not enough. Any RGB raster image or its disk file has 3 channels. The difference is in linear.
I think no gamma correction is done but I’m not sure. If no gamma correction has been done, then that can explain the darker image.
The pixel values in the Linear DNG are still in the linear domain, they are still in the native color space of the sensor, like in a true RAW file. When you open them in, for instance, Adobe Lightroom, and make your adjustments there, the color and contrast are indistinguishable from what you would have obtained by opening the original RAW file in Lightroom.
There’s also a gamma correction during the normal conversion. I believe something as 2.2.
But still no explanation what is meant with linear.
From your blog As we already have observed, the lens is linear. The sensor is also linear—at least if no saturation occurs—and thus the data in the RAW file is also a linear function of the amount of light in the scene. Even the first steps in RAW conversion are linear. But at one point during the processing, nonlinear steps take place. In particular, the color rendering and the gamma correction are non-linear functions. You want your exposure adjustment to be applied before these non-linear functions and JPEG files don’t allow you to do that. With RAW files, however, where the entire RAW conversion is applied in postprocessing, adjusting the exposure in a linear way is possible. The same applies to white balance, highlight recovery, and many more.
Now we know more.
Further Now that we have recalled the basics, we can introduce Linear DNG: While (normal) DNG files store unprocessed RAW data, Linear DNG files store intermediate results of RAW conversion, with some processing steps applied—but only linear ones. Therefore, they provide the same flexibility as RAW files for adjusting color and contrast.
regarding darker thumbnail issue , I already report to service center , waiting for their reply.
I found a phenomenon if you add more files at the same time , you will see brightness of thumbnail are all normal in the begining , it just like embedded JPG , after (less than) 0.5 second , thumbnail become darker one after one .
because DxoPureRaw support cache memory , if you add same file next time , you will see the darker thumber immediately , to see this phenomenon again , you must modify all file name before add files .
for example : A1.CR2 / A2.CR2 / A3.CR3 rename to B1.CR2 / B2.CR2 / B3.CR3
I provide 3 files for your testing
That’s normal. When you open an image for the first time the embedded JPG is shown in the thumbnails. As soon the convertion is finished it’s replaced by a new thumbnail of that image. When you load that image a second time the thumbnail from the cache is used.
Copy the image to a new location from outside PL and you will see the same happening again.
Did you read the link @platypus gave?
True – and without testing any of the new files – what you see first is the embedded jpg, then replaced by a recalculated result.
BTW, when I tried your “Swamphen” the other day, with DxO PL 4.3.1 standard preset it came out nicely and too dark when only applying optical corrections (similar to PureRaw).
have fun, Wolfgang
I’m sorry but I am going to have top repeat it yet again…
As George has also said, the image that you are seeing is a JPEG which has already been processed in the camera. It is not the true RAW image and, as you can see, once DxO has had the time to replace the JPEG preview, it shows the true image, which is quite often different from the JPEG.
There is nothing wrong with either PR or PhotoLab. They are only working correctly and, with PR, if you export a RAW file, your will get the same rendering as the RAW file which, in your case, is darker than the JPEG.
Just read that link from @platypus. Linear DNG is a file format for partially developed RAW images: it allows performing different parts of the RAW conversion in different photo editing applications This allows combining their strengths and opens new creative possibilities.
Each sensor pixel only presents a brightness value… and only when knowledge about the filter matrix is added and taken into account, will a colour image appear.
This image needs to be adjusted with the multipliers for r, g and b pixels, multipliers that depend on the Bayer filter characteristics and white balance - and on whatever the raw developer adds to the mix.
This is normal. there is nothing wrong with PureRAW. It does exactly what it is intended to do.
PureRAW is just a converter and denoising tool. It does not alter the RAW in any way.
Don’t use software that displays a JPEG preview of the RAW file to compare with the resulting DNG.
Look at one of the files you have opened in FastRawViewer
This is what your file looks like when you look at the JPEG preview, which is what you see most of the time in other image viewing software…!
…screenshot 1
What I did this time was to switch the FRV from displaying JPEG files to displaying RAW files…
…screenshot 2
This is the image that PureRAW denoised and converted to DNG, not the first one.
The purpose of PureRAW is to give you the cleanest linear RAW file possible so that you can process it in the software of your choice. That’s all.
Joanna
Yes , Chinese translation is OK to me , but I am from Taiwan .
we use traditional Chinese , it’s quite different from Simplified Chinese which use in China .
I am sorry for my poor English , my writing ability is not so good , but I can reading , no need to translate to Chinese .
