Random hot pixels appearing with edits on RAW files in Photos

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Level 1

8 points

Random hot pixels appearing with edits on RAW files in Photos

Hi all

I've imported a couple of hundred RAW files from a Canon EOS M5 camera and have noticed odd, 'hot pixels' appearing in the photos in random places when applying editing tools e.g. sharpening, vignette etc. If I zoom in/out, the placement of the glitchy pixels changes randomly, so I don't think it's an issue with hot pixels in the files. Deactivating the editing tools causes the hot pixels to disappear, activating them again brings them back, in different places. I'm on the latest OS, have been in touch with chat support who suggested various resets that I've tried but they haven't worked. Next step is to call Apps support but I thought I'd try the community in case anyone else has experienced this.

Using MacBook Pro 13.3" 2015, 8GB/128GB, High Sierra 10.13.4

Thanks

Posted on Apr 22, 2018 2:26 PM

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Answer 1

Best reply

léonie

Level 10

194,733 points

Apr 23, 2018 11:28 AM in response to jpw80

Does it work to revert the RAW files to original and to edit again?

Do you still have the originals on the card? If yes, make. a new library for testing and import the RAW files again. I'd try to use a differnet card reader or a different USB port this time.

You could also test in. different user account, to check if the problem is system wide.

How to test an issue in another user account on your Mac - Apple Support

A system wide problem could mean, that there is an incompatible color profile installed, third party kernel extensions interfering, or a hardware problem, for example a problem with the graphics card.

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Answer 2

jpw80 Author

Level 1

8 points

Apr 23, 2018 11:31 AM in response to léonie

Hi many thanks for the reimport suggestion from the card - I did this with a sample of the images and the issue did not recur on those copies. I had also got 'optimise storage on this Mac' to keep the original files on the cloud and only download originals when editing - I guess it could be that the original RAWs are becoming corrupted somehow. I'm going to keep the originals on this machine in future, as I'll be doing more editing going forward and it will avoid having to wait for the files to download each time.

Thanks again

John

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Answer 3

léonie

Level 10

194,733 points

Apr 23, 2018 12:09 PM in response to jpw80

Hi many thanks for the reimport suggestion from the card - I did this with a sample of the images and the issue did not recur on those copies.

That is good, that you still had the photos. For future imports I would keep the photos on the card as long as possible, just in case that the problem should occur again. It could have been a loose contact during the transfer, or similar.

Or, as you suspect, a problem when downloading from iCloud.

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