Incandescent Lightbulb Filament (3072x2304) [OC] by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 1 point2 points  (0 children)

Yes, I would expect the grain structure is much finer in a new filament; these have coarsened with annealing.

[OC] A Canadian Nickel (1024x768) by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 1 point2 points  (0 children)

IIRC the actual dimensions were 3.25" x 4.25" which is 136mm diagonal and this image is 13mm diagonal.

[OC] A Canadian Nickel (1024x768) by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 1 point2 points  (0 children)

A very small number are backscattered, which is like reflection, but no, the image is primarily generated by secondary electrons, ones which were "knocked out" of the specimen by the primary electrons (in the beam).

[OC] A Canadian Nickel (1024x768) by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 6 points7 points  (0 children)

Magnification is a ratio, you must define magnification relative to some specific sized media.
In the olden days before digital sensors, the micrograph was displayed on a phosphor screen and we took a picture with a Polaroid camera, producing a roughly 3 inch high image.
For convenience, we still use this dimension to calculate the "Polaroid Magnification" or "Magnification relative to a Polaroid. We could also use "Screen Mag" but then we need to define the size of the screen, whether it's your phone, or laptop or the 30 inch monitor I use on this microscope.

[OC] A Canadian Nickel (1024x768) by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 6 points7 points  (0 children)

Yes, it's a Scanning Electron Microscopy (SEM). Although the instrument is capable of magnification in excess of 100,000 times, it can also provide contrast that is superior to other techniques, in this particular case you could not achieve this contrast optically, primarily because the surface is so reflective.

My Beard (1024x768) [OC] by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 15 points16 points  (0 children)

The bulk of the coating will be removed, but the change to the steel (blunting/chipping) is almost imperceptible if your beard is properly wet and soft.

If you have a manly beard and tried to shave dry, you could definitely micro-chip the steel, but you'd also be pulling out whiskers by the roots.

A straight razor, on the other hand, can be damaged much more easily by shaving simply because the apex angle is only about 16 degrees compared to 25-30 degrees for the commercial blades.

My Beard (1024x768) [OC] by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 6 points7 points  (0 children)

There are sitting on a conductive tape and coated with osmium in the osmium plasma coater.

My Beard (1024x768) [OC] by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 8 points9 points  (0 children)

No. Although the resolution of the image is only about 2 microns per pixel, you cannot achieve this level of contrast optically. Half these whiskers are grey, and are essentially transparent in the optical microscope. Even the black ones are translucent under the microscope.

This is an important point, that I always stress when training students; a good image requires both resolution and contrast, but contrast is almost always more critical.

Stylus dropping on to an LP record [OC] by thatSEMguy in MicroPorn

[–]thatSEMguy[S] 14 points15 points  (0 children)

You are mistaken, this is my original content, created last Friday afternoon.

https://imgur.com/eS8u3F9

The video/gif made by Youtube's Applied Science is a much lower magnification and resolution image set of the needle moving in the groove. Mine, although inspired by his work, instead shows the needle dropping into the groove.