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Cornerfix for R-D1s?

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docolmo

Guest
I have just learned to use Cornerfix 0.9.1.9 on the M8. Just the right tool to correct vignetting and cyan shift for my CV 21 and 25mm lenses. And I used the ExpoDisc to create the lens profiles for apertures f4, f5.6 and f8. It works!

My question: I tried to correct the vignetting problems on the R-D1s, but doesnt work (even after using Adobe DNG converter to convert the .ERF files to .DNG). Is the author/creater thinking of extending the application's functionality to other cameras? Would appreciate, too, if the final release version has preference setting for default profile files folder, and working images folder. Just a suggestion.
 
S

Sean_Reid

Guest
Write to Sandy and ask him. There should be an e-mail listed in the program docs. He's a great guy.

Cheers,

Sean
 

sandymc

New member
I have just learned to use Cornerfix 0.9.1.9 on the M8. Just the right tool to correct vignetting and cyan shift for my CV 21 and 25mm lenses. And I used the ExpoDisc to create the lens profiles for apertures f4, f5.6 and f8. It works!

My question: I tried to correct the vignetting problems on the R-D1s, but doesnt work (even after using Adobe DNG converter to convert the .ERF files to .DNG). Is the author/creater thinking of extending the application's functionality to other cameras? Would appreciate, too, if the final release version has preference setting for default profile files folder, and working images folder. Just a suggestion.
If by doesn't work, you mean it complains about "unsupported camera", then just ignore that; it does actually work on an RD-1 dng. In fact, it will work with just about any camera with a bayer sensor. If you mean something else by doesn't work, then you need to tell me what that is.

As regards the default profile and image folder settings, CornerFix should open in whatever the most recent folder you used for those....

A quick warning on ExpoDisc - it can create vignetting all of its own under certain circumstances, so you can get strange results from it if you use it to generate profiles. The ExpoDisc folks have confirmed to me that this is an issue.

Sandy
 
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docolmo

Guest
Thank you, Sandy.
I realize ExpoDisc has its own inherent vignetting issues, since for white balance its the middle of the image that counts. But for correcting the cyan effect of the IR filter, its better than nothing.

If I really have to use a grey card, do I have to have it in focus for the purpose of capturing a reference file? Vignetting is only serious with wide angle lens, and therefore at closest focusing distance of 0.7m for Leica lens, I cannot get the entire A4 Kodak grey card to cover the whole frame. Can I bring the camera very close to the card, but causing it to be out of focus? It's the colour and luminance balance that I am interested, right?

Going back to R-D1s files, Cornerfix won't calculate native .ERF files. It will load the .DNG converted files (using Adobe), but doesn't eliminate the vignetting that occurs (see attached jpeg).
 

sandymc

New member
It's usually actually better to have the image a bit out of focus.

Re the image, how are generating the profile? Note you can't use an M8 profile for an R-D1, even for the same lens......you have to generate an R-D1 specific profile......

Sandy
 
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docolmo

Guest
For the R-D1s, the native raw file is .ERF.

1. I can open the .ERf file in cornerfix. A pop-up dialogue box will say "DNG processing error: File format is not valid." Below the window is says "No decodable Makernotes found. But it will open in the left window, but you can't do anything further.

2. If I try to create the profile under the "Lens Profile" menu, same popup dialogue saying DNG error appears.

3. So, what I did, was, convert the .ERF file into .DNG file using Adobe DNG converter that came along with Photoshop ACR plugin 3.4.1

4. Open again the new DNG file, and it loads on the left window and automatically shows a similar image on the right window. A warning appears saying that it is an unsupported camera model, but I ignored it.

5. I created the profile under "Lens Profile Menu" and I got the image as shown in jpeg in my earlier post. As you can see there's some colour vignetting on the right window.
 

sandymc

New member
Hmm, that's strange. And I assume you haven't changed the chroma setting in the options? Can you send me the erf or the dng?

Sandy
 

sandymc

New member
Getting it now; may take a few days for me to be able to get to the bottom of the issue, but I'll post here when I have an answer....

Sandy
 

sandymc

New member
Ok, took a look at the image. What is happening is that the image is very dark - on a linear scale, the center is at about 12.5% of full scale - and coupled with the way black levels are set in the Epson, it's throwing off CornerFix's compensation system. This couldn't happen on the M8 because the M8's black levels are configured in a differerent way to the Epson.

Two things to do here:

Firstly, I need to improve CornerFix's handling of near black level images - no promises, but I should be able to do that in the next version.

Secondly, while you wait for that, I'd suggest trying to reshoot a reference image that's a lot brighter - at least two stops brighter....

Sandy
 
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docolmo

Guest
Thanks Sandy. Will do.
But will future Cornerfix releases open other raw files directly? At least for rangefinders with severe vignetting problems.
 

sandymc

New member
No, I'm afraid I have no plans to extend CornerFix to open raw formats other than DNG. Pretty much any raw format can be converted to DNG via Adobe's converter (which is free), and then processed in CornerFix. There's no loss of data or any loss of image quality, so there's really not much value to having CornerFix opening other raw formats, other than avoiding a step in the workflow.

Sandy
 
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docolmo

Guest
Sandy, took some reference files with two stops over-exposed, but seems to have resulted in not much improvement. Well, I'm not shooting much with the R-D1s nowadays since having got back my M8 (faulty switch and backfocus problems). Anyway the Epson doesn't suffer from cyan vigneting, only brightness, and that can be cured (albeit trial and error) within Photoshop.
 
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