3 ms·

I understand you're trying to help, but everything you are suggesting is basically not helpful. Microscopists are savvy enough to match sensors and lenses, it'

by dekhn 3y ago

I understand you're trying to help, but everything you are suggesting is basically not helpful. Microscopists are savvy enough to match sensors and lenses, it's typically called "diffraction limited" (https://en.wikipedia.org/wiki/Diffraction-limited_system https://en.wikipedia.org/wiki/Diffraction-limited_system) based on the Rayleigh criterion (https://en.wikipedia.org/wiki/Angular_resolution#The_Rayleigh_criterion https://en.wikipedia.org/wiki/Angular_resolution#The_Rayleig...). I rarely if ever hear microscopists refer to nyquist limits. They would not overimage something at a higher magnification, or more correctly, they would be aware it was happening and either downscale or not worry. Next, when you make a point like "we can get a 1TB SSD for under $50". It shows you're not understanding the domain microscopists work in. Their scopes typically cost $100K (with a camera for another $50K, and a stage that costs $10K). The cost of the storage system (or parking the data in S3) for 10 years is usually far less than the capital cost of the scope, or the operational expense of maintaining staff on site. I believe the effective resolution can already be computed from the captured metadata, which includes the objective's numerical aperture, as well as the frequency used for imaging (many microscopes today use lasers to image with a very specific frequency to cause fluorenscence, which itself has a fairly tight output spectrum).

zackmorris 3y ago
Thanks those are better terms. I remember doing a test where the camera photographs a ceramic plate with an almost perfectly black diagonal line to calculate the effective resolution, but I can't remember what it's called, maybe the diffraction limit. It's basically a measure of how blurry the image is, where a matched lens and sensor would look like a Bresenham line with no antialiasing. TBH, I think that the scientific community has huge blind spots, mostly due to its own gatekeeping. Some of the things like this that seem to be a struggle remind me of the design-by-committee descent of web development. The brilliant academic work of the 1990s has been mostly replaced by nondeterministic async soup and build processes of such complexity that we have to be full stack developers just to get anything done. All the fault of private industry hoarding the wealth and avoiding any R&D that might risk its meal ticket. Starving the public of grants, much less reforms that are actively blocked like UBI. Now nobody ever seems to step back and examine problems from first principles anymore. That's all I was trying to do. Edit: I found the term for calculating the effective resolution of a camera with a high-contrast diagonal line, it's "slanted edge modulation transfer function (MTF)": https://harvestimaging.com/blog/?p=1328 https://harvestimaging.com/blog/?p=1328 https://www.strollswithmydog.com/the-slanted-edge-method/ https://www.strollswithmydog.com/the-slanted-edge-method/ https://www.eckop.com/resources/optical-testing/resolution-testing-methods/ https://www.eckop.com/resources/optical-testing/resolution-t...

by dekhn 3y ago

zackmorris 3y ago

Thanks those are better terms. I remember doing a test where the camera photographs a ceramic plate with an almost perfectly black diagonal line to calculate the effective resolution, but I can't remember what it's called, maybe the diffraction limit. It's basically a measure of how blurry the image is, where a matched lens and sensor would look like a Bresenham line with no antialiasing. TBH, I think that the scientific community has huge blind spots, mostly due to its own gatekeeping. Some of the things like this that seem to be a struggle remind me of the design-by-committee descent of web development. The brilliant academic work of the 1990s has been mostly replaced by nondeterministic async soup and build processes of such complexity that we have to be full stack developers just to get anything done. All the fault of private industry hoarding the wealth and avoiding any R&D that might risk its meal ticket. Starving the public of grants, much less reforms that are actively blocked like UBI. Now nobody ever seems to step back and examine problems from first principles anymore. That's all I was trying to do. Edit: I found the term for calculating the effective resolution of a camera with a high-contrast diagonal line, it's "slanted edge modulation transfer function (MTF)": https://harvestimaging.com/blog/?p=1328 https://harvestimaging.com/blog/?p=1328 https://www.strollswithmydog.com/the-slanted-edge-method/ https://www.strollswithmydog.com/the-slanted-edge-method/ https://www.eckop.com/resources/optical-testing/resolution-testing-methods/ https://www.eckop.com/resources/optical-testing/resolution-t...