Posted 11/26/2012 10:43 (#2717954 - in reply to #2717230) Subject: Re: Do you have a microscope?
Microscopes are all about quality. First you need to determine what you're doing.
A "dissecting" or stereoscope has depth perception (within the focal plane or what isn't blurry) and generally can magnify from a few X to around 70x in the higher priced versions. Lighting is important to see anything, some have light from underneath, some have light from above, some have it where you can move it and aim it. A stereoscope is less common than the standard lab microscope and probably will cost more per X magnification, but will show you a lot more. You can look at surfaces of thick objects instead of having to always be able to look at thin stuff that light can pass through from underneath.
A regular laboratory microscope may be binocular or have a single eyepiece like the old ones did. Have an old one from the 1950's that my father used to examine semen back when they used "fresh" cooled semen and before fozen semen was commonly available on many bulls here. It still works just fine for what it was. Have to get a nice bright light to shine on the mirror to get enough light into it or have sunlight because of the single ~600X objective it has. they would have been happier with a lot lower magnification probably around 100, but I don't think they used it much, they quickly figured out how long they could safely keep extended semen on each bull in the refrigerator before throwing it out and collecting again.
Magnifications above about 400 in most microscopes are practically useless without professionally prepared slides or maybe for microbiology. Most objective lenses for much greater than that are oil immersion type and unless you are looking at bacterial cells, the "yield" isn't much for the expense of the lens. I would get one with more lower magnifications maybe a 10X on the low end instead of starting at 40. Lots of microscopes have 40, 100 400 1000 0il immersion. I think you will use 10,40,100,400 more. Or maybe one with something between 100 and 400.
Light source intensity, color and the collumator beneath the stage are very important to the performance of the microscope.
Good scopes are "parfocal" I believe it's called. When you swivel another objective into position, the focus doesn't change (much!) That way you don't spend as much time finding the focus. Just grab the fine focus and adjust slightly.