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If you are not sure what microscope to choose you
have a few options.
You can read and learn, or try to use other peoples
knowledge.
First, you have to decide what work you intent do
with it.
Then you contact the company who lists many
different microscopes and explain right from the beginning your purpose
for the product.
If you are lucky, you may get an altruistic person
who will give you some ideas. I would suggest contacting at least two
companies, just to verify if you are getting some common answers.
Never
forget, that as in many other areas of buying, you only get what you pay for.
The higher the magnification you require, the more
distortion you will get, unless you go for top quality brand name
products. But again, in some instance, with low power microscopes, even
a
less costly unit will give you satisfaction.
If we want to save some funds, we may find decent reconditioned
microscopes, mainly because microscopes sold years ago were mostly
brand names and one can buy a sound, good quality reconditioned microscope for
a fraction of a
new one of the same brand today.
Do not forget to compare only apples to apples. Never
mix your apples with oranges.
A 10 year old Carl Zeiss or Leitz may cost you
the same
or more as a new generic product.
But with a
reconditioned name brand you may get a great working tank with a lifespan
exceeding ours.
If you surf the Internet and go site to site,
you may find many similar looking generic products with different names
and brands. Under the word
Generic I picture microscopes manufactured in China, India and basically
manufacturers who exist for only a few years and do not have the history of
the best brand name products.
But, like the whole world, all is changing and as
you know very well,
yesterdays Japanese underdogs like Olympus and Nikon are today in the
same class with Leica, Carl Zeiss and leave some old brand names biting
their lips.
The simplest and most straight forward choice is in
Stereo
microscopes. Known also as dissecting microscopes. Their heads
are used in Operating microscopes and Microtones. Because we are dealing
with low magnifications, the distortions are not so great and there is a
huge choice of different manufacturers and product lines to completely
satisfy a wide scale of buyers.
From basic models of Stereo microscopes with
transmitted & incident illumination stands, with fixed or turret
nosepieces with two magnifications for few hundred dollars you go to
more sophisticated lines of modular
microscopes. There you can build up scopes with different Zoom features,
multimedia attachments, illuminations, all meant to supply one thing.
Fulfill your task! Never forget that purpose and try not to buy one with
all whistles and gadgets. You may get overkill. With one exception only.
Trinocular head, which is with today’s technology valuable interface
to your computer, camera or one of them, which you may purchase years
from now. The head in the Stereo microscope is the most important and
costly part.
The Compound
microscope family is the most known and largest one. From simple
monocular unit through binoculars, you have to decide in choice of
Bright Field, Phase Contrast, Dark Field (almost forgotten, but alive
and kicking again in live blood analysis).
Also Polarizing microscopes, Fluorescent and many
other specialized units.
In compound microscope the total magnification of
the microscope should be approximately 400x to maximum 1000x the
objective aperture, according to
Ernst Abbe, (the range of
"useful magnification").
With the exception of Special Hematology in labs or hospitals and
Live blood analysis research, anything more the 1000X is nonsense. You
can successfully view specimen under more then 1000X with the best (most
expensive) objectives only. If some company sells or advertises cheap
scopes with magnifications of 1200X or more, they are selling a dream.
Some techniques
like Bright Field microscopy are quite straight forward and we can use
many different makes and models to get some results. The more light
interference you do the better quality unit you need. Dark field and
Phase Contrast microscopes are sold in generic models also, but the
results are less then adequate. It is a Phase, but it needs a genius to
make something out of it. Same goes for Dark Field and so. Fortunately,
so far only the best guys have the guts to manufacture Fluorescent or
Confocal microscopes.
As for the attachments (beside Trinocular for
multimedia), buy only what you need.
I saw scopes from the best manufacturers collecting
dust or with a line-up, only because the buyer purchased a costly toy.
Toys for boys? As far as I am concerned, only one person can sit in
front of one scope. And it may have a Bright Field, Dark field, Phase,
Fluorescent attachments and Fontana De Trevi built-in, only one
individual can perform one task at one time.
Beside the point that so many features are found on
the most upscale units for which you will pay the same price as for
several scopes. The salespeople just love it
Joseph Zeman
January 26, 2004
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