Choosing the Right Microscope – Basic buyer’s guide
There’s no one perfect microscope – just as there’s no one perfect car.
We can help you choose the best microscope for you based on your needs and budget.
Here are a few of the basics.
Compound or stereo?
A compound microscope is designed for ‘smaller’ transparent specimens, such as microorganisms, pollen, pond scum and blood. It has higher magnification (40x-1000x). Essentially, the bigger the number quoted, the higher the microscope’s power, and the more intricate the level of detail visible.
A stereo microscope is designed for more substantial specimens, such as insects, bugs, minerals, circuitry and plants. Typically, such specimens require lower power (10x-40x). Stereo reveals an object in all its 3D glory.
Hobby or professional?
For home use, a serious look at student microscopes is the go. Some of these have high-quality optics and there are some superb choices available for under $500.
For professionals or enthusiasts, a laboratory microscope will be a better fit. These are much more expensive but have a wider array of features to match – better performance, utility and comfort. Designed for frequent use, lab microscopes are essential for anyone spending any significant amount of time behind an eyepiece.
The microscope you want has four essential features. All other things being equal, you want to consider the eyepiece arrangement and the right lens for the job. But don’t overlook usability and comfort – the best microscope for you is the one you actually enjoy using.
The most obvious difference between microscopes is the eyepiece arrangement.
You will need to decide on whether you want a monocular, binocular or trinocular microscope. That is to say, a microscope with one, two or three eyepieces (or oculars).
Monocular heads are the simplest and cheapest, especially good for young kids. Binocular heads are more ergonomic and preferred by most adults. Trinocular heads are similar, but they have a third eyepiece for connecting a microscope camera, allowing you to capture images or video of your samples.
While the price ranges overlap, typically a monocular microscope is the least expensive type of microscope with trinocular being the most expensive.
Objective lenses and magnification
In a compound microscope, the lens closer to the eye is called the eyepiece. The lens at the other end is called the objective.
The lens inside the eyepiece usually magnifies the specimen to 10 times its actual size. Combined with the eyepiece, an objective lens with a power of 40x magnifies the specimen to 400 times its original size.
Most compound microscopes come with 4x, 10x and 40x objective lenses, which will be the most useful and will create some fascinating images. A 100x objective might be useful, too.
Stereoscopes tend to have a fixed dual magnification setup – that is, they switch between 20x and 40x – or a continuous zoom. With continuous zoom, you can adjust the magnification anywhere within the available range, such as from 5 to 50x.
Objective lenses vary greatly in design and quality, depending on their intended purpose.
If you’re using higher magnifications or just engaged in careful work, it’s a good idea to ensure your prospective microscope comes with both a fine focus control knob and a mechanical stage.
Fine control is very important under high magnifications, as small adjustments are crucial and can be difficult to achieve with coarse controls only.
A mechanical stage will move your specimen smoothly – invaluable for delicate samples or high magnification work where any disturbance can easily disrupt a sample or pull it out of focus.
Today, high eyepoint eyepieces are very popular, even with people who do not wear eyeglasses, because the large eye clearance reduces fatigue and makes viewing images through the microscope much more pleasurable.
A widefield objective lens can also reduce eye fatigue in longer sessions.
There is such a thing as too cheap. Try to purchase from a reputable vendor to ensure decent build quality and access to a reasonable returns policy.
Learn how to maintain your microscope and lenses. Neglecting your equipment is guaranteed to result in expensive damage and unnecessary replacement. A well-treated microscope will serve you faithfully for years to come.
If you would like any assistance in choosing the right microscope for your application please do not hesitate in contacting us directly.