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C1 noise reduction "creating" hot pixels ?

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41 comments

  • BeO
    Top Commenter

    little red dots on the small preview images from the Fuji GFX50sii.  On the larger image it's not visible. 

    with "larger preview " you mean when you zoom in, or do you mean a larger preview size in preferences and regenerated previews?

    Can you post a screenshot here?

    Did you already rule out that it is not the exposure warning?

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  • philip brosens

    Thank you for your reply.  It's very odd behaviour both on Windows and Mac.

    They show mostly up in the small preview in the sidebar.  Sometimes they would also appear on the "big" picture, but then disappear when zooming in.  If I put the color or detail slider in noise reduction to "0" instead of the default value they disappear and they don't seem to re-appear when I put the slider back to normal.

    Sometimes it's red dots - other times they show up as crosses.

    In the photo I have included there are red and blue crosses in the small preview in the sidebar - in the "big preview" nothing shows up.

    Sometimes it's dots, sometimes crosses and they are never in the same position in different photos, so it can't really be hot pixels generated by the sensor.

    The photo is taken with the GFX50sii at iso 6400 s 1/7.7s


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  • BeO
    Top Commenter

    Did you try already to disable the hardware acceleration in preferences, then select the small thumbnails in the browser and "regenerate" the previews? (in menu "Image", and have "Edit all selected" enabled)

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  • philip brosens

    On my Macbook (IOS Monterey) the hardware acceleration is disabled, so I thought I'd put it on automatic but then a message appeared that the hardware acceleration is not working.  I have no idea why.  So I put it back to "never".  My windows desktop is much more powerful with 64gb ram.  I'll try later because at the moment it's "occupied".  With my Windows desktop if I open photos in the Windows viewer I have not noticed no pixels or crosses.  Neither in the Fuji software that comes with the camera.

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  • Abbott Schindler

    Do the red dots appear in output files (JPEG or TIFF)? That would be the real test for me.

    C1 uses at least 2 types of previews. A low-res one is used for displaying thumbnails in the Browser's multi-view and single view windows. When you zoom to 100% it uses higher-res thumbnails whose resolution is set in Preferences. I occasionally find artifacts in the lower-res views that completely disappear in when viewing the high-res magnifications, and they also don't show in the output (files and prints).

    You could also disable hardware acceleration as BeO suggested. I have it turned on in all of my machines, but apparently many people find problems with it.

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  • philip brosens

    Thank you for trying to help me.

    I've just switched on my WIN desktop (win10).  I started C1 without changing any settings and now all is fine.As it was much more visible on that monitor I thought to show a screenshot.

    I feel such a fool.  No red dots, or red and blue crosses all over the image.  Everything OK.  I have no explanation.  I've shut down and restarted C1 three times and all is OK.

    My camera is brand new and they're the first photos so I hadn't exported them yet in jpeg or tiff.  If it shows up again I'll do that straight away.

    Thanks again.

     

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  • BeO
    Top Commenter

    Ha, maybe the "occupier" has fixed your PC for you :-)

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  • philip brosens

    Hahaha I doubt it, but there has been an update of the nvidia graphics driver today ... maybe that did the trick.

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  • philip brosens

    I spoke too soon.  I reopenend C1 and it's worse than ever.  On the big preview they show fraction of a second before disappearing.  On the small preview in the sidebar they remain until setting the noise reduction sliders to zero and then it goes away.

     

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  • BeO
    Top Commenter

    Did you regenerate the previews after the driver update? Test this.

    If it doesn't help, disable hardware acceleration in preferences, regenerate previews and check again.

    Do the exported images have the same issue, as Abbott has mentioned?

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  • philip brosens

    Could it be an issue with the processing of the RAF-file from the Fuji GFX50s ii ?  I never had any problems with NEF images from Nikon D850 or the RAF- files from the XT2. 

    Today, in only photo I found a red dot  - yesterday they were all over the place.  This time not in the small image in the sidebar preview, but in the larger image.  Zooming in it disappears and exporting it in jpeg it does not show. When I did a complete reset of the image the red dot disappeared.

    As long as the exported images are ok and it's not a sensor issue I can live with it, but the GFX is not a cheap camera and it got me worried.

     

     

     

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  • BeO
    Top Commenter

    Today, in only photo I found a red dot  - yesterday they were all over the place.  

    So it is very unlikely that this is related to your specific camera. Very likely related to the updated driver. Did you check this?:

     Did you regenerate the previews after the driver update? Test this.

      If it doesn't help, disable hardware acceleration in preferences, regenerate previews and check again.

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  • philip brosens

    Thanks again for your input.

    I forgot to mention that I had regenerated the previews.  Sorry about that.

    It is indeed strange that I seem to have this problem only with the files of the GFX50s ii both on Mac and Windows and Nikon files are OK.

    So far I'm just testing the camera and I haven't taken any important photos with it, so today I had the bright idea to create a new catalog and import the same photos in the new catalog.  At the moment all images are displayed correctly.

    I closed and restarted C1 two or three times and still all images are displayed correctly.

    It's a mystery ;-)

     

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  • BeO
    Top Commenter

    Wait until tomorrow :-)

    btw, do you like the new camera, and what?

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  • philip brosens

    Oh, I really love the image quality.  I must admit that I only do stills and for my type of photography the contrast only AF is not really an issue.

     

    Regarding the dots and crosses I spoke too soon.  As soon as I did an adjustment (turning down highlights) they re-appeared in that photo.  Then every time I selected a photo to work on the dots appeared in that photo (even without adjusting it).  It seems to happen only in photos from iso 6400.

    Here are two examples.  I brought down the exposure on purpose so the dots are very clear.

    The jpegs are OK.

    ps.  After resetting the image the artefacts disappeared and I could do adjustments without them re-appearing ... for the moment.

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  • Abbott Schindler

    The screenshots help. Do you by any chance have Exposure Warnings turned on?

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  • philip brosens

    No it's all switch off - overexposure and underexposure.  As the dots and crosses are all blue or red I also changed the overexposure warning to yellow and underexposure to green just to be sure ... but no change.

    I've just taken photos of a dark wall at iso 6400 and 8000.  At first all was ok - the image was clean - and now the photos at iso 6400 show blue dots and the photo at iso 8000 is still ok.  

    As with the other photos, when I reduce the slider of colour or detail in the noise reduction to "0" the dots disappear.

    I've downloaded the silkypix software that comes with the camera and there there are no artefacts.

    If they were stuck pixels they'd show up from the beginning when I import them into C1 I suppose.

     

    Could it be an error with the lens profile ?  I'm using the GF50mm and that one is not in the list of supported lenses.

     

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  • BeO
    Top Commenter

    I downloaded an image from the same Fuji model from here:

    https://www.imaging-resource.com/PRODS/fuji-gfx-50s-ii/Y-GFX-50S-II-JG-0500.RAF.HTM

    (Edit: corrected link)

    This is a screenshot crop from a C1 browser thumbnail, max zoom

     

    This is from the preview in the viewer, 100%:

    (color noise slider set around 70)

     

    I tested this image in DXO PL5, no such issue.

    I can confirm it randomly appears and disappers in C1, also (but not exclusively) depending on zoom level. And I can confirm that color NR plays a role here too.

    C1 seems to have an issue here, you should submit a request / bug report.

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  • BeO
    Top Commenter

    In this image, it is in the lake. The funny thing is that it is hard to reproduce. Color noise value 67. When zoomed in to 100% and then panning the image, it disappears, but it happened that another blotch appeared in another location. Same image, after panning a little bit:

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  • BeO
    Top Commenter

    And sorry I posted the wrong link, here's the correct one:

    https://www.imaging-resource.com/PRODS/fuji-gfx-50s-ii/Y-GFX-50S-II-JG-0500.RAF.HTM

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  • philip brosens

    Oh thank you very much for all your work.  I really appreciate it.  I have submitted a request.

    Before the latest update of this C1 I would have those huge red and blue blocks in the image, but they would disappear when zooming in ... as if C1 needed a bit of extra time to create the image.

    Last night some images had really bad red and blue "pixels" and when I regenerated the preview, a couple disappeared, but many more would show up.  Some images lit up like a christmas tree.

    They seem to show up at random.  Here's another example. 

    The 2 photos below have exactly the same settings iso, aperture, shutter and were taken seconds apart.  Yet, those dots/crosses appear in different places.

     

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  • philip brosens

    Long exposure noise reduction on the camera is set by default to "on". 

    Last night I took two photos on iso 6400 and iso 8000 and both  1/13 sec  with the camera long exposure noise reduction set to "off"  (even though I wouldn't call 1/13 sec long exposure and I thought it only impacted jpegs) ... well,  those images are clean.

    A clash of noise reduction between C1 and GFX ?  A bug in the GFX system would also show up in other software like DXO or ON1 I suppose.

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  • SFA

    Philip,

    Out of interest, what size of Preview file are you using for the import process?

    When you mention that zooming seems to reduce the problem it occurs to me that C1 may be at the point where it goes back to the RAW file and completely recreates its working temporary image in memory rather than using the original preview. 

    If so it might suggest that the problem display is related to Preview processing at the currently chosen size. That could be a quick and easy experiment to try out in the hope of obtaining a closer understanding of the problem to report to the Support Team.

     

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  • philip brosens

    Hi

    Thank you for your suggestion

    I keep the preview size at the default setting of 2560.

    I have made 3 screenshots.

    The first is at the default 2560 pixels.

    The second is the same photo at 1440 pixels ... the preview in the sidebar is clean, but all of a sudden the blue pixel on the big "preview" has changed position.

    The third is a different photo, but with the same camera settings and at the default 2560 pixels.  Here  long exposure noise reduction in camera is set to "off" ... clean image here.

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  • philip brosens

    I absolutely love Capture One and I've been using it for many years, but every time there's a new version it is filled with bugs and it takes weeks to be ironed out.  At one time I even reverted to a previous version because the new one was completely unusable with my "processing" getting lost every time I closed the program and having to start all over again from the beginning.

    I'm starting to get tired of this.

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  • BeO
    Top Commenter

    In this case you probably can't go back to an older version because of the camera support.

    I know what you mean, for "production" I still use 13.1 (v20), for play around I use 15.1. (v22), until I'm sufficiently confident that it won't harm serious work.

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  • SFA

    Philip,

    Purely as an experiment, you could try recreating the Previews for 2 or 3 known problem files larger than 2560. 

    Try something like 2880 and 3840. 

    The strange cross shapes of the red and blue spots are likely related to the sensor technology in some part. 

    If your screen is native 2560, C1 would need to downscale a larger preview dimension to "fit" but I think it will do that in-memory based on the existing preview file if the preview is up to a certain amount larger than the native screen size.

    When you zoom in there will be a point at which C1 abandons any attempts to scale up a Preview file and takes the extra time to totally recalculate, ground-up from the original file, in order to re-load the working memory content for the image. I think that is where you are seeing the "spots" disappear - during the recalculation. 

    I could be wrong of course, but again it's quite a quick test to undertake.

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  • philip brosens

    Thank  you for your suggestion. I'm certainly willing to try.

    I changed the preview to 3840px and 5120px and regenerated the previews each time.  The blue crosses have gone ... they've become red and changing from 3840 to 5120 some disappeared, but others showed up.

    The photos taken with Long Exposure Noise Reduction to "off" remain clean with no artefacts at all.

    Well, I suppose I can rule out that something is wrong with camera and that's a relief.

     

    What I haven't tried so far is to take photos and save with no compression.  Now I save them as lossless compression.  I could try that tomorrow.

     

     

     

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  • BeO
    Top Commenter

    Your thumbnails always show more crosses than your previews, is that correct or a wrong interpretation because you zoomed in the preview thus covering only a part of the image?

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  • philip brosens

    That is correct.  I have not zoomed in and the thumbnails are far worse.

    In the previews I would more often get big blocks of blue or red like in the examples you posted.  They disappear when zooming in.

     

    I've discovered another quirk - sometimes when pressing the "undo" button it would jump back to a photo I was previously working on ... maybe I should volunteer to be a beta-tester in the future :-)

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