Taking microscope images of onion skin is supposed to be an elementary exercise usually not worth the efforts of serious hobbyists. I found it pretty hard to do. For one thing onions make gaseous fumes which tend to fog lenses. I also found the skins difficult to gracefully cut. Anyway I got some pictures that show the range of form of the cells. I sampled various points of view. Don't laugh but I found photographing onion skins to be challenging.
https://youtu.be/Tol06VWEO-M
The Onion Skin Devil
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Re: The Onion Skin Devil
Onion skins are nice to look at and are worth the effort IMO. One simple way to prepare them is as follows.DonSchaeffer wrote: ↑Thu Apr 25, 2024 7:44 pmTaking microscope images of onion skin is supposed to be an elementary exercise usually not worth the efforts of serious hobbyists. I found it pretty hard to do. For one thing onions make gaseous fumes which tend to fog lenses. I also found the skins difficult to gracefully cut. Anyway I got some pictures that show the range of form of the cells. I sampled various points of view. Don't laugh but I found photographing onion skins to be challenging.
https://youtu.be/Tol06VWEO-M
1. Cleanly cut a ring of fresh onion, then cut it into two arc forms. Leave it for some time on the table or bench, to let the offending vapors and droplets to vanish.
2. Prepare a drop of water on a clean slide. Prepare a pair of tweezers.
3. Take an arc and make a deep cut that ALMOST halves the arc into two shorter arcs. That will leave a thin skin. The skin is almost transparent, flimsy and curling. Pull apart the two ends while bending, to peel off the skin. Cut a 1-2cm section of it (even less is enough). Pick it up with the tweezers and dip into the water on the slide. Try to flatten it, but even if only a small part is flat, fine.
4. Cover with a coverslip, gently press to remove excess water.
5. If properly done, a single-cell thick layer will be observed. Overlapping folded over sections will show up but the view will still be nice.
6. Using a drop of stain (I think that even simple blue ink will do) instead of water will improve the contrast.
7. For preserving the sample for a week or two, seal the edges of the coverslip with nail polish.
8. Note that there are two skins, of the onion ring - external and internal. The both look very nice.
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Re: The Onion Skin Devil
Thanks for that methodology. I obviously didn't do much to prepare my specimens and the product shows it.
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- Posts: 3399
- Joined: Sun Mar 22, 2020 10:06 am
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Re: The Onion Skin Devil
I agree