Earlier today, I put an N95 mask under my microscope, to see how wide the spacing is between the fibers of which it is comprised. I used two different methods to photograph the result.
First, here is a picture taken by a method that I've used for years, which produces a moderate-quality image, but for which I've worked out all the bugs and all the relevant calibrations. With the 10× objective and the 15× eyepiece in place, I used a cheap point&shoot-type digital camera pointed into the eyepiece. The numbered scale that you see in this image is built into the 15× eyepiece, and when used with the 10× objective, the space between the numbered ticks represents a distance of 122 microns. A micron is 1⁄1000 of a milometer; a millimeter is usually the distance between the smallest ticks on most metric rulers.
From this, we can see that the gaps between fibers in this N95 mask are typically around 50 microns or so. Cheaper surgical-type masks, and almost certainly nearly all fabric masks, surely have even larger gaps. So, anything about fifty microns or so should be able to get through this mask; get down to about ten or twenty microns, and this mask would be no obstacle at all.
The #CoronaHoax2020 virus ranges in size from about 0.05 to 0.2 of a micron. At the smaller end of it's range, the #CoronaHoax virus is about a thousand times smaller than what this mask can reliably be expected to block.
My 10× objective, with a numerical aperture of 0.2, can theoretical resolve detail down to about two to four microns. My most extreme objective, a 100× oil-immersion objective with an NA of 1.25, can theoretically resolve detail down to about 0.3 to 0.6 of a micron. So, at 0.2 of a micron, the very largest #CoronaHoax2000 virus is smaller than I can possibly hope to be able to see with my microscope.
View attachment 341827
I very recently acquired an adapter to connect my much-better camera, a Nikon D3200, to my microscope. This goes in place of the eyepiece, only using the objective as the only optical component. I've still got some bugs to work out, as far as using it to get the best image, and as far as calibrating the combinations of my D3200 connected via this adapter, to my different objective, as far as how size is scaled. The image below was taken using the same 10× objective that I used to take the above picture. I took three different pictures, focused slightly differently, and focus-stacked them, to improve depth-of-field.
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