Nyquist and Image size

Posted by Renato A. Mortara on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Deconvolution-of-Transmission-Images-tp7393699p7455788.html

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Dear all,

Having attended the first Pawley course in Vancouver I feel highly
embarassed to ask this, but I would really appreciate a clarification:

When estimating the highest zoom users should apply to their sample in order
to accommodate for the Nyquist theorem, I estimated the optimum pixel size
value by dividing the lateral resolution (eg: 0.2 microns) by 2.3 so that
the value is approxiametely 90 nm.

The doubt: if the image size is increased from 512x512 (having adjusted the
zoom to the pixel size of 90nm) to 2Kx2K, the resulting pixel size
(displayed by the system - Leica) the pixel size decreases 4 fold, to 22.5
nm. Since the resolution obviously did not change but only the image size,
what happens to Nyquist and the optimum pixel size at 2Kx2K ?

Many thanks !

Renato

Renato A. Mortara
Parasitology Division
UNIFESP - Escola Paulista de Medicina
Rua Botucatu, 862, 6th floor
São Paulo, SP
04023-062
Brazil
Phone: [phone]
Fax:     [phone]
email: [hidden email]
home page: www.ecb.epm.br/~ramortara