Posted by
Tim Feinstein on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Nyquist-sampling-advice-for-a-short-talk-tp7591495p7591517.html
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I must be weird, because I find that a fairly complex concept like the denoising feature of deconvolution makes the overall lesson about sampling much easier to teach. Most trainees aren't ready for a physics lecture, but they get that an algorithm can flag a signal as 'real' as long as you sample with enough resolution to make sure that each point source shows up in two adjacent voxels. Since the intensity of a noise pixel is uncorrelated with any adjacent pixel, you can detect most of them and filter them out. Then I explain how the imaging system & sample prep determine the PSF size, and I show trainees how to find a PSF calculator like the one SVI has on their site when they need to work out the necessary dimensions for themselves (no commercial interest; why doesn't Autoquant's website have one?). I think the focus on problem solving helps with retention. All the best,
T
Timothy Feinstein, Ph.D.
Research Scientist
Department of Developmental Biology
University of Pittsburgh
On 11/12/20, 8:49 AM, "Confocal Microscopy List on behalf of Moulding, Dale" <
[hidden email] on behalf of
[hidden email]> wrote:
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Wow, thanks for all the responses. As a biologist I admit some may have gone straight over my head (the fourier domain will likely remain a place of mystery and magic to me), but I’ve got plenty to get my teeth into here. The plan is to keep it nice and simple. Nothing too much more technical than my checkerboard mouse mat that's regularly used as a Nyquist teaching tool. Love the applets, these will be really helpful.
Cheers
Dale
-----Original Message-----
From: Confocal Microscopy List <
[hidden email]> On Behalf Of Glyn Nelson
Sent: 11 November 2020 08:38
To:
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Subject: Re: Nyquist sampling advice for a short talk
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Hi Dale,
I found (via Twitter I think) this video by Peter Evennett. As a practical demonstration of resolution about half way through it is excellent, and may be easier to grasp for students than the purely dry physics theory. Mind you, beware that it is using transmission rather than reflection, so the 2 NAs are not necessarily the same for the calculations, so this may confuse them further!
https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D60_jgZtyR6U%26t%3D2468s&data=04%7C01%7Ctnf8%40PITT.EDU%7C41ed5352ae574cc3059708d88711b786%7C9ef9f489e0a04eeb87cc3a526112fd0d%7C1%7C0%7C637407857447790338%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=FCJ1iamWAtfD8bAQBBP2puPouKdpuK0ZsxYTu4W6dVo%3D&reserved=0 about 20 mins in and further on. Even demonstrates the difference with wavelength. Really well done I think.
Otherwise, I'd '+1' Avi and Craig's answers.
Glyn.