http://confocal-microscopy-list.275.s1.nabble.com/sCMOS-salt-n-pepper-issues-tp7583323p7583325.html
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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
>