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Would it be possible for someone to give a simple introductory 
explanation of what this is all about? It all sounds great but many of 
us do not have the background to appreciate what is being said.

Relative to cameras, microscopes, and scanning images, I'm talking about:

Sampling/detection in general
Over/under sampling, consequences thereof
Aliasing
Nyquist limit
Bayer masks
etc. with regard to the concepts in this discussion.

Please reply to the list and if someone is up to an article in 
Microscopy Today it would be a great service

Ron Anderson, Editor
Microscopy Today

Hans-SVI wrote:
> Search the CONFOCAL archive at
> http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal
>
> Hi Doug,
>
> (message from commercial vendor)
>
> At least some answers to your questions:
>
> <snip>
>> If undersampling is the cause of potential artifacts, how does one 
>> check their optical system to make sure it is sampling at a high 
>> enough level?
> To compute the critical Nyquist sampling rate see: 
> http://support.svi.nl/wiki/NyquistCalculator
>>
>> How does the Bayer color mask on most single chip color CCD cameras 
>> affect oversampling issues?
> The Bayer mask consists of windows of 2 x 2 cells like this
> G R
> B G
>
> (IIRC there are some cameras with four different colors instead of three)
> In photo cameras the per-pixel colors are interpolated so it seems 
> there are 4 RGB pixels per 2 x 2 window. But in terms of sampling the 
> blue and red channel have only 50% of the sampling frequency in both X 
> and Y directions. The green channel has a larger bandwidth area, but 
> this does not matter because it is the weakest link here which counts.
> In practice this means that if you want to match optical bandwidth 
> with a Bayer sensor you need, for the same imaging field, 4x as much 
> pixels as with a 'grey' sensor and filter wheels.
>
> -- Hans
>