Posted by
Straatman, Kees (Dr.) on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Nyquist-sampling-advice-for-a-short-talk-tp7591495p7591503.html
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But does this not assume that your objects is in de squares. What if the objects are in between two squares? Dividing by 2 would just result in 4 squares with more or less the same intensity. So, I normally advice to divide by 3.
Best wishes
Kees
Dr Ir K.R. Straatman
Advanced Imaging Facility
University of Leicester
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From: Confocal Microscopy List <
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Sent: 10 November 2020 16:42
To:
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Subject: Re: Nyquist sampling advice for a short talk
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GIven that most microscopy has the luxury of being a simpler specific case
of the Nyquist sampling theorem, I like to simplify it to a discrete model
using a checkerboard. I first show a grid of squares and ask, "What is the
smallest feature we can resolve on this grid?" I then show a checkerboard
pattern next to a grid with all white squares. I point out that in order
to resolve two objects means to be able to distinguish between two point
sources and one bigger solid source. Therefore, you need to sample not
only the peak intensities (your resolution) but also a local minimum
between them to distinguish a pair of points from a solid object.
Therefore, you need to sample at 2x your resolution.
The hope here is to give people an intuitive sense of where Nyquist
sampling theory comes from without delving into more complex issues like
aliasing.
On Tue, Nov 10, 2020 at 8:26 AM Sara Parker <
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wrote:
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Benjamin E. Smith, Ph. D.
Imaging Specialist, Vision Science
University of California, Berkeley
195 Life Sciences Addition
Berkeley, CA 94720-3200
Tel (510) 642-9712
Fax (510) 643-6791
e-mail:
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