Most
people believe that only the experts have the skills to examine the quality of
used microscopes. That is not true. You can actually do the examining yourself
– you just need to know the parts to be observed and what factors to examine
when you need to see its functionality. There are different kinds of
microscopes out there and sometimes, the used ones are as good as new. Here are
the guidelines which you can use in purchasing used microscopes:
The
Features
The
first thing you want to do is to see the features of the used microscopes.
Ideally, you want to look for a metal body so it will ensure durability and
ease in handling. It is also ideal to get a metal rack-and-pinion focus to
ensure accuracy and precision. The lens should also be made out glass, not
plastic, as it gives off a better focus. You want the lens to focus different
thickness of slides, as well as the surface of objects with at least one-inch
thick. If you are looking for compound microscopes, be sure to check the 3
lenses and the diaphragm. This will ensure you that the microscope is able to
control the brightness.
The
Quality of the Lens
It
is important to check the quality of the lens so the specimen can be viewed in
accurate ways. Most people use special equipment for it but you can do well by
just looking at the types and the factors that should be in it. Basically you
want to have a lens with:
No
deformation – Examine closely the lens and you want to have a flat surface.
Both the horizontal and vertical engraved lines should be straight.
No
dirt – All the lens of microscopes can be detached. Before you can actually
test if all the lenses are clean, detach it from the microscope and see signs
of dirt. The dirt will defocus the specimen causing the image to be distorted.
If the microscope has multi-element lens, and you see that there are signs of
dirt – do not buy it. As for used compound microscopes, check the three-lens
turrets. All the turrets should be perfectly aligned so adjusting it to certain
magnification should be easy. Most of the time, the alignment of the lens comes
with a price. Cheaper used microscopes usually are priced cheaply. Be aware of
that.
Other
Factors
It
is good to know the microscopes do not wear out. They are just being sold
because they are not as useful as before. However, there are used microscopes
that have damaged parts. This will reduce the precision and accuracy in viewing
a specimen. Make sure that you choose used microscopes with functional parts,
and only deal with credible sellers.
Used
microscopes can amount to $1000 or more. This will depend on the brand and type
of microscope you will use. They have been in the business for years so you can
rely on their advice and high quality products.
