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I am currently using Lightroom Classic v14.0.1 on Windows 11.
Flat Field Correction has been working previously on scanned negatives. However, when I try to use it now there appears to be no affect or alteration of the files. The "task bar" in the top left corner appears to finish, but there is no correction applied nor is the DNG file created. I have verified by checking the source folder for a DNG file, looking at photo in library and develop tab, tried various layouts (correction image first and last), correcting one photo to multiple, tried different locations, restarting PC, etc.
Is this a recent bug? I am using the same workflow as before and it appears to be broken right now.
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I am experiencing a similar problem, although I didn't put 2+2 together that it occurred after the update. Previously, I was able to easily apply FFC to a large number of negatives with a single calibration frame. Now, if I try to do a large group, Lightroom will grab other non calibration frames and use them for calibration, creating ghost images in the .dng files. Another issue seems to be that trying to do a FFC on negative that even slightly resemebles a calibration frame (e.g., an open landscape), Lightroom seemingly does not know which one is the calibration frame, so does nothing. This is a major issue as FFC is essentially unusable right now and is important for the workflow of many people doing film scanning. The FFC needs to be able to do the following:
1) the user should be able to tell Lightroom which frame is the calibration frame rather than the program making a guess and frequently getting it wrong.
2) the user should be able to force a FFC for any frame, rather than Lightroom mistaking a photo needing correction for another calibraiton frame and doing nothing
3) the user should be able to apply FFC to a large number of frames without it resulting in ghost images as Lightroom uses the wrong frame for calibration
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Hi! I tried Flat field correction with one image, and one calibration file and it worked fine. Please share a set of images on which this isn't working, along with a screen recording. Thanks!
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Hi Pavan - thanks for getting back to me.
Here is a screenshot of a photo to which flat field correction will not work. The photo needing correction is on the left, and the calibration frame is on the right. This is a photo of a 35mm film negative, and landscape. When attempted, the photo remains .RAF, it does not apply correction and change to .dng. My suspicion is that Lightroom does not recognize that this photo is not also a calibration frame, and as such does not apply. Photos such as this with very little features (open sky, open ocean) will not work with flat field correction. I have come across others reporting the same issue with these types of photos.
I've attached a screen recording as well showing the file is left unchanged after applying flat field correction. I was able to apply flat field correction to other photos from this roll of film, but this photo and those similar to it would not apply.
Also, can flat field correction only be applied to one photo at a time? Doing multiple photos did work for me in the past, but now it does not as Lightroom chooses the wrong photo to use for calibration and instead creates ghost images as it uses non calibration frames to apply correction.
The ideal fix would be for the user, not Lightroom, to specify which is the calibration frame and tell Lightroom to apply it to all the selected photos, rather than Lightroom attempting to decide which is the calibration frame, which seems to be the root of the issue in my experience.
Thanks again for your assistance, very much appreciated!
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I am having the exact same problem. Out out a roll of 36 image, FFC works on less than half. I have experienced both issues described here. If I use a single calibration frame at the begining or end of a roll, I get the issue discribed with random images being detected as calibration images and applied to others, causing artifacts and ghost images.
If I try interleaving calibration frames, half of the images just do nothing when trying to apply FFC. I am able to select the calibration and target frames and click apply, but nothing happens. The progress bar quickly flashes in the top corner, then no change is made to the images and no DNG file is generated. The feature is completly broken and I can no longer get usable scans on over half of my images.
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Hopefully @Pavan Kumar T S and his team can remedy the issue. Like I've said, I think the main problem is Lightroom choosing what it thinks is a calibration frame, rather than the user. The user should be able to tell Lightroom which frame is a calibration and apply it to any number of selected images. Leaving Lightroom to decide seems to lead to unpredictable results, or Lightroom thinking a different photo is the calibration frame, and doing nothing.
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This feature would appear to simply be designed incorrectly. Need to be able to manually create and save profile corrections, choose from them, etc. Automatically detecting the calibration image is not a reasonable way for this to work.
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In my experience, what you are experiencing has always been the case. I used to assume that once it finishes without any error dialogs appearing, it was done with all of them. One day I happened to look at the folder where the images are and to my horror, only about half of the frames were corrected. Not a single error message about missed frames.
And frankly, that's one of my smaller issues with it. It will randomly start using a non-flat-field frame during a batch operation and then I end up with a lot of frames that have ghosts of the image LR used as flat-field frame. You want to undo the operation? No, you can't, for whatever reason this operation is not undoable. You can delete the files in the filesystem and force a re-sync to get the originals back but that's not how it's supposed to be.
Another issue I've been having is a dramatic lightening of all my frames after the "correction". I have not verified whether this stems from the wrong flat-field frame described above but if not it's it should also be fixed.
And as a general question that I'm fairly certain won't be answered: How does the flat-field correction work exactly? I spent quite a bit of time trying to learn how it's done so I could write my own and the way flat-field correction is supposed to work needs a dark frame to be used along with the flat-field frame. LR can only work with a flat-field image so I'm assuming it's doing something with masking? In any case, this is not an issue in and of itself.
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Yes, I had the same experience. I thought all of the frames had been corrected, as one would expect, but it had skipped frames, as in my example below. I had gone forward and completed all of my editing by that point.
It's operation seems obscure, and there is some conjecture on my part that LR chooses which frame, but that would explain all of the errors.
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As you can see @Pavan Kumar T S , this is an issue a large number of LR users are experiencing, and this is only a fraction of the number I have come across on various photography forums. Have you been able to review my examples? Is this something Adobe will work to fix? With film photography and at-home digital scanning become more and more popular, I think this is a feature that many users will be utilizing going forward and some optimization would be appreciated.