contributed by Chuck Huck, USA |
Editor's note: I'm sure we've all acquired tips, techniques, 'tricks of the trade' or perhaps made simple gadgets while pursuing the fascinating hobby of amateur microscopy. Why not share some of yours with our readers, who may not have come across them. Just send us a short note in an e-mail (contact in footer), enclosing a scanned picture or drawing if you wish and we would be pleased to compile, upload and acknowledge your contributions.
Field telescope / microscopeWhile on field trips or simply walking through the woods, one often wants to travel light. A good instrument to take along is the Celestron 6X telescope and 30X microscope. This combined unit has a pocket clip and weighs virtually nothing. It is surprisingly good quality, with coated optics and a slip-on lens that converts the telescope to a microscope. Use it to observe birds, wildlife, flowers, etc. Then use it to examine insects, tree moss, plant life and similar objects at 30X magnification. I have even used it in the field to observe pond specimens collected in a Petri dish, or some shallow receptacle. To keep the unit perfectly still, you can rig up some sort of clamp and miniature tripod. This is especially helpful is observing specimens for extended periods and eliminates "shaking."
Using a small lightweight compound microscope as a field microscope
Some microscopists have purchased small, portable hand-held microscopes, such as the Swift or similar models, to carry into the field. These do indeed serve a purpose, especially when extreme portability is a desired. However, these small units, especially the Swift, can be very expensive. I have obtained a couple of standard Graf Apsco microscopes (on eBay) sans lenses, with the stage, base, coarse and fine focusing, etc. in great shape. I have taken another standard body I had (the lightest among the others) and made it into a portable carry-along scope for use in the field.
Although I use a bino' scope and a couple of other professional scopes in my amateur work, I found that setting up a field scope was not all that difficult, provided that one has access to a few things. One is that the body be standard and not a "toy" scope. The one I have made into a field scope has a disk diaphragm and built-in 0.65 condenser. It has a turret and an attachable mechanical stage, which is not all that important in field work, especially when collecting pond samples.
I have equipped this scope with a 10X objective and a 10x WF eyepiece. This gives 100X magnification, generally fine for most pond viewing. On this scope, I have removed the mirror and instead use a small flashlight that can be adjusted to the right angle and a small piece of ground glass placed over the light and inserted just beneath the stage opening. It provides ample light. (Take spare batteries for the flashlight.) This is because there may be no outlets to plug in a lamp.
I have tested this set-up and it works fine. If darkfield is needed, it is a fairly simple matter to cut a piece of clear plastic tape and glue a small patch stop and center it over the widest opening in the disk diaphragm, since an Abbe condenser is not attached. You must size the patch stop to the opening. Experiment. Use tape to attach the the entire stop system to the bottom of the disk diaphragm. I have found you can also use the flashlight and move it about to achieve darkfield if the stop is not centered exactly. If you have an Abbe condenser in your field set-up, there is no problem.
I chose the scope that is lightest, although others have an Abbe condenser but are much heavier. This system is a great field setup, albeit a bit more cumbersome than a hand-held scope. Obtain a padded camera bag of sufficient size, and you have a good carry-along scope. Include in the bag a small slide box of blank slides, some cover glasses, small jars, vials or what-have-you, pipettes, separate magnifier, and whatever else you feel you need.
Useful containers - 35 mm film canisters
Plastic 35 mm film canisters are often discarded, but they can have a multitude of uses for the amateur microscopist. The cap design varies a bit between makers, but some caps are watertight enough to hold small pond water samples. If out on a walk, just pop a few canisters in the pocket in case you pass a habitat of interest. They are also useful for keeping small nature samples moist or undamaged while bringing back for inspection e.g. small flower heads, or smaller fungi. Also handy for storing samples of sand from the beach. Not to mention their use for general storage of samples like forams and dried samples of many types ... but don't forget to label! The canisters can sometimes be big enough to be used as dust proof containers for smaller eyepieces, and objectives.
In addition to film canisters, the clear plastic containers that are supplied with objectives make handy collecting vessels. These most often have screw lids that, if screwed tightly, form a leakproof container. It is best, however, to test each of these types of containers with water before collecting actual pond samples.
Your local photo print shop will probably have hundreds of unwanted canisters, so they may be prepared to give you a bagful free of charge.
Cleaning pipettes
When using glass pipettes to transfer samples from pond water containers, the pipettes often become stained and caked with pond debris. Simply flushing water through the glass tube often will not remove the inside coating. Purchase a package of soft pipe cleaners and a package of hard-bristled cleaners for really stubborn stains. Moisten the cleaner with water and run it through the tube several times, turning the pipette a few times back and forth. You may have to bend the cleaner in half and use both halves. Use the cleaner without bending for the narrower glass tip. Then your glass pipettes should look like new and be ready to transfer another pond sample to a microscope slide.
Contributions above by Chuck Huck, comments welcomed.
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