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You got one! Martin and I were debating whether we should try one of those microscopes out ourselves, but ended up doing nothing as usual. Can’t wait to see some photos. :)
Oh, I feel dumb, I should’ve sent you a polarizing filter while I was at it. You totally don’t need anything fancy. I cut out a circle and put it in my eyepiece. That just stays there… permanently reducing the light transmission. :) The other is just a random square cut-out which I stick on top of the illuminator by hand. That way it’s super-easy to turn the polarization on and off and rotate. I bought a sheet from… beats me. Found one cheap somewhere on-line. Bought two, actually, one super-cheap, and one smaller but high-quality one for about the same price. Figured the one which ended up permanently part of the eyepiece should be high quality. (The only trick was getting it to lie flat on the inner surface of the eyepiece and to not let any dust in when disassembling and reassembling the eyepiece.)
About the PPD I sent you. It’s just a minute quantity, but even that little should last you a lifetime. With a pair of tweazers put one tiny crystal in one of the beer bottle caps, crush it with the end of the tweazers, then place two drops of ethyl or denatured alcohol on it (one drop evaporates too fast!) It dries out after one or two uses. No problem, just add another drop or two as necessary. Rinse it out at the end of the day with alcohol, otherwise it oxidizes and messes up the results. It should be clear in solution. You know it’s oxidizing when it starts turning reddish and eventually black. Pretty much anything it touches, even the most minute quantity, will eventually turn black. So be very careful with it. Even a particle of dust on your shirt or table will leave a permanent mark. (And it’s carcinogenic, did I mention?) Also, note that the reaction takes a while to proceed, unlike K and C test which are essentially instantaneous in most cases. Since you never want to test part of an herbarium specimen (or it will stain the whole thing black over time in your drawer!), what I do is break off a tiny fragment of a whole bunch of things I want to test, and arrange them neatly on a piece of toilet paper on something safe, then test them all in parallel at one time. Saves a whole lot of trouble to do a bunch at once. The color typically leaks out onto the paper, making it pretty easy to diagnose (but not always). (Incidentally, that’s a good way to do K and C tests on dark things like Bryoria, too. Or “blot” the place you applied the K/C with a piece of toilet paper and read the color off of the paper instead of the specimen. In cases where the algae and other factors make the test ambiguous on the specimen, this can be a godsend.)
I think I got an at least a basic idea now, I’m planning to get a polarization filter when I have money for it (I have a few other things to get first like a reticle).
And how high of a quality scope do you mean? This is the type of microscope I got – http://cgi.ebay.com/...
The polarizing filters are expecially helpful for Lecanora. Almost required, actually. (Remember, the point is to place one below the specimen, and another above the specimen at 90° to the first. This will block all light except light passing through crystals which tend to rotate the polarization. The result is crystals pop out clear as day, while everything else turns a murky dark bluish-black.)
The rest is going to be practice, practice, practice. Very sharp razor blades are a good thing, making it much easier to do clean super-thin cuts of apothecia. Lugol’s or Melzer’s reagent can be helpful, but unless you have a super high quality microscope (do you??) you probably won’t be able to read ascus stains, anyway. (At least, I’ve given up until I improve the optics of my setup.)
I now have a microscope, so I am one step closer to first base with these. Needing a polarizing filter was mentioned in an earlier observation. What else do I need to know to start preparing (As funds allow) to do some microscopy on these?
Created: 2011-05-26 12:33:18 CDT (-0400)
Last modified: 2011-05-26 12:33:19 CDT (-0400)
Viewed: 57 times, last viewed: 2017-06-09 13:59:55 CDT (-0400)