http://confocal-microscopy-list.275.s1.nabble.com/sCMOS-salt-n-pepper-issues-tp7583323p7583328.html
Maybe I am missing the point here but won't the characterization paper that has been cited in this discussion- (but not yet read by me) produce at least a Dark Current image and hopefully a an image of the dark pixels on a lighter background. These two images could be used with some combination of multiplication and division to at least give a better looking image. I would have to spend more time than I have at the moment to consider the implications for quantitation, but whether you are trying to measure light intensity or count objects, background correction operation rarely cause problems, and usually help.
If you can send me the two images cited and a sample image I woul be happy to play around with them and post my results back to you and/or the list.
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> Hi all, I hope the
> science/optics/hardware/software/students/post-docs/
> reviewers/managers/next-door-neighbors and FedEx are treating you well.
>
> We have a couple of issues with a recently installed Hamamatsu Flash
> 4.0 sCMOS camera and I was wondering if anybody has had any similar
> experiences, both in terms of feedback on what is expected from sCMOS
> hardware and what can be done to rectify any issues.
>
> Here's what we're seeing:
> Using a Hamamatsu Flash 4.0 camera link sCMOS (firmware v3.00A) on a
> spinning disk and acquiring data using Perkin Elmer Volocity 6.3 we're
> having three issues regarding hot and cold pixels. So far we have
> tried 4 different sCMOS cameras (kindly supplied/tested by Hamamatsu
> and Perkin Elmer), to double check the subtleties, but the results are
> quite similar
>
> On the first camera we saw a bright cluster of 4 pixels that are
> between 2 and 10x greater than the surrounding pixels across nearly
> all imaging conditions (not seen in the other three cameras). Are
> these bright pixel clusters something that others have seen much? This
> issue is seen in both Volocity and ExCap/HDImage, but was not seen on
> the test sCMOS camera used to cross check. I also see 'ghost'
> clusters that look similar but only seem to last for one frame...
> Again, is that something seen in sCMOS cameras in general?
>
> Salt:
> In images with low signal and longer exposure times we see speckled
> bight pixels using both Volocity and ExCap/HDImage, with an intensity
> approx twice that of the background signal. Exposure times ~secs; low
> signal <1000 counts per pixel. These speckled hot spots were seen
> with all sCMOS cameras to some degree.
> Pepper:
> In almost the inverse situation, where we have higher signals with
> lower exposure times were also seen on all sCMOS cameras (the first
> camera with the clear hotspot had very bad 'peppering' compared to the others).
>
> I know that the pco cameras used on the Deltavision OMX have reference
> images applied to reduce the affects of these artifacts, and I was
> wondering if that's something that can be applied post-acquisition.
> Any thoughts and/or feedback on what's normal for an sCMOS, and how to
> get the best out of these cameras would be much appreciated. sCMOS
> cameras certainly are fast and have a great signal to noise, so am I
> expecting too much from this generation of hardware?
>
> Thanks
> Neil
>
>
> A couple of images to compare salt'n'pepper pixels seen on three
> cameras are here:
>
https://drive.google.com/file/d/0BzfJAGNfrgieQ21abmVPbFBqY0k/> view?usp=sharing
>
https://drive.google.com/file/d/0BzfJAGNfrgieVjViTWNoeExpdDQ/> view?usp=sharing
>