Microscopes?

Question

If you were looking to purchase a microscope, what would be 5 features that you would look for and why?

Answer 1

You have to know what you want to use it for first. If you're looking at slides, you need a compound microscope, but if you're looking at leaves, rocks, bugs, etc, you want a stereo. And what to look for is different depending on the type.

I'll assume that you want a compound, because that's what "everybody" thinks that they want (I'm partial to the stereos)

1) Get one from a well-known manufacturer. The fact that they have been in business for a long time indicates that they have decent quality. It also means that repair/spare parts will be more available and that part interchangeability should be good. Finally, it means that if you decide that microscopy is not for you, you should get a decent resale price. Get a scope that is heavy and solidly built. The controls must work smoothly and with no slop.

2) Good illuminator. You need to be able to set Koehler or critical illumination. If the sales person cannot show you how to do it with the scope or you do not see it in the instruction manual, RUN! If you buy a scope online, you can find instructions for setting Koehler or critical illumination online also. Just make sure that it is possible.

3) A good condenser. The condenser is just as important to the image formation as the objectives. The condenser should be fully adjustable. The numerical aperture of the condenser should equal or exceed that of whichever objective lens has the highest numerical aperture. If the condenser numerical aperture is not specified, move on

4) Quality objectives. The higher the numerical aperture, the more detail you can perceive. Surprisingly, this is more important at low magnifications. At high magnification, unless you are doing microscopy for a living, I would bet that you would be very hard pressed to tell the difference between a 100x 0.9NA lens and a 100x 1.3NA lens.

BTW, never buy a microscope based on the maximum magnification, particularly if they advertise something like 1600x. About 1000x is as good as it gets - at least in the world of the kind of money that you and I have. I have a Zeiss 100x 1.3 NA planapo with a 1.4 NA aplanatic/achromatic condenser. Some of the best glass that you can buy. And I spend most of my time with the 40x and lower powers. There's just not that much to be seen at high magnification.

5) Adjustable eyepieces. Yes plural. Get a binocular microscope. It is waaaayyy easier on the eyes than a monocular. At least one of the eyepieces should be adjustable so that you can achieve proper focus with both eyes at the same time.

6) Mechanical stage. You will want some means of moving the slide and your pudgy little fingers are not up to the task. Get a scope with a decent mechanical stage.

Go for a used scope - Zeiss, Nikon, Leitz, etc. Optics do not wear out (but they can get fungus and other problems from improper storage). They are plentiful on eBay and from other sources. You should be able to get a really decent scope in the 500 - 1000 dollar range, depending on what all is included. Possibly less if you are patient.

Objectives, from lower quality to higher quality are referred to as
1) no specification
2) achromats
3) plan achromats
4) apochromats
5) fluorites (Zeiss calls them Neofluars)
6) planapochromats

There is no difference in quality between fixed tube length microscopes (usually 160 mm, but some are 170 mm) and the "infinity" optics.

Join the Yahoo Microscopy group and ask this same question.

Answer 2

you're suitable: the compound easy microscope could be maximum suitable. collectively as the electron microscope (for my area) is a techniques extra unique in this is outcomes, it works maximum suitable with dehydrated matters.