How to Choose a Student Microscope

If you are a beginner shopping for your first microscope or a parent or grandparent buying a microscope for your favorite explorer, you need to carefully match the microscope features with the intended level of use. The basic choice is between a toy microscope and a student microscope, and if you choose a student microscope, you need to carefully check the features.

Toy Microscopes

A toy microscope is not necessarily a bad thing (virtually all microscopes under $100 are toys, regardless of the advertising claims - especially claims regarding magnification.) Toy microscopes can be useful if you want to foster an interest in microscopes and science, and if a toy microscope accomplishes this, it may be money well spent. A toy microscope is also a good choice for a parent who simply wants to test the waters to see if a child has an interest in science. 

However, if the student's interest grows beyond that initial spark, you are faced with buying another, more expensive microscope. Toy microscopes often make exaggerated claims as to magnification and performance, but make no mistake, toy microscopes lack the features needed to learn all the basics of microscope use. Also, toy microscopes do not have the durability needed for extended work. Product lifespan at this price is predictably short. As educational tools, a toy microscope will be a step below the features and quality of a microscope used in even an average elementary school classroom. If you are trying to duplicate what a student actually uses in school, a toy microscope is the wrong choice. You need to spend more and get a student-grade microscope. Prices begin at $100 for a student microscope with the minimum recommended features and run up to $150-200 for a student microscope with all the recommended features.

It takes more than an advertising label of "student" to make a microscope similar to what is actually used in a classroom these days. For projects and other applications that actually require you to use (and learn how to use) a microscope, a student microscope is required and that is always a matter of features, not a label. Fortunately, the list of features needed to qualify as a student microscope is short and these features are listed in the product description, when present. You do not have to be a microscope expert to select the right microscope for a student.

Why Dual Focus Is Important for a Microscope

A compound microscope with only one focus knob is nearly impossible to use at high magnifications, mainly because it is too easy to fly by the very precise focus point you encounter at high microscope magnifications. Equally important though, at high magnifications we also need to focus DOWN through the specimen since we are magnifying not only in terms of specimen width but also specimen depth. In other words, by carefully focusing with a fine focus knob, we discover that we can see down through different layers of a semi-transparent specimen, and each layer reveals different features and detail. This is one of the first lessons taught with a microscope, at least in my classroom. This type of work and the fine control required cannot be done with a microscope that features only one focusing knob. You must have a microscope that offers fine focus, and that is only found on microscopes with two focusing knobs. I consider a microscope with both a coarse focus and fine focus to be an absolute must for any student microscope. Under $100, the only model with that essential feature is the Konus College microscope, but this model does not have any of the following recommended features.

Built-In Light for a Micsocope 

Next in importance, though not absolutely essential, is a built-in light. You can get by with a microscope that uses a mirror and an outside light source such as a desk lamp if money is an issue, but a microscope with a built-in light allows a student to concentrate on observation rather than struggling to supply enough light to even see the specimen. As a former science teacher, I promise you that not having a built-in light on a student microscope is a handicap to learning. Another thing to consider is that most mirror microscopes, meaning a microscope with no built-in light, also typically come with crude light adjustment controls to keep the price down. This is yet another handicap since the ability to adjust light correctly is an essential part of learning how to use a microscope (models with a built-in light usually come with more advanced features for controlling light). By the way, we are talking about a serious light, here. The tiny little LED lights found on toy microscopes do not count as a useable microscope light. 

Mechanical Stage on a Microscope

This is a movable bracket that holds the slide in place for you and it allows you to move the slide in tiny increments via vertical and horizontal controls without actually touching the slide. Less expensive microscopes use stage clips to hold the slide for you, but you must move the slide with your fingers. Clips work well enough at low power but create problems at higher magnifications for a student due to the very narrow field of view a microscope at high magnifications. As a result, the first thing a student discovers at high magnifications with stage clips is the tendency to move the slide too far one way or another as they try to center the specimen in the field of view with their fingers. Several attempts are typically needed by a beginner to center the specimen in the field of view. This can be time consuming and frustrating - not something you want when working with a student.

A mechanical stage solves this problem by allowing you to turn a knob and move the specimen very precisely into position. The next thing a student discovers with stage clips is that just touching the slide with your finger at very high magnification is enough to move the specimen out of the field of view. In fact, there is enough adhesion (stickiness) between your finger and the glass of a slide to move the specimen at high magnifications when you lift your finger from the slide. A mechanical stage eliminates this issue, since you fingers do not touch the slide. Lastly, a mechanical stage that is a calibrated version will have markings which you can use to record the position of a specimen. By checking your notes, it then becomes a simple matter to move the slide back to that same position at a later date and find your specimen instantly rather than starting your search all over again. All in all, a mechanical stage makes life much easier for a student. Not absolutely essential in a student microscope, but highly recommended.

Binocular Options for a Microscope

Binocular head or binocular eyepieces are recommended for advanced students and/or long sessions. Using only one eye with a microscope produces eye fatigue since the muscles of one eye are being strained differently than the muscles of the other eye. As a result, you walk away from a long observing session with a monocular microscope with a dizzy feeling or even a headache. A binocular microscope solves this problem since you are producing an equal strain on each eye, and all binocular microscopes allow you to adjust the distance between your eyes for maximum comfort. The key consideration with this feature is the length of time you will be observing. For college level and professional work, where you often use a microscope in terms of hours, a binocular head is nearly standard. For much student work, however, a monocular head is fine and a good option when budget is an issue.

Stereo Microscopes

Keep in mind that we have been talking about compound microscopes so far. Compound microscopes use slides, offer very high magnifications, and are used to observe very small specimens such as cells and organisms in pond water. Compound microscopes are the type of microscope most people think of when they hear the word microscope. There is, however, another type of microscope called a stereo microscope that is not as well known but also very useful. The specimen size determines when you use a compound microscope vs. a stereo microscope.

Applications of a Stereo Microscope

Large subjects - twigs, rocks, leaves, flowers, gems, industrial parts, and so on, don't require the high magnification of a compound light microscope. However, they do require much more room under the microscope due to their size, in some cases as large as a rock. A stereo microscope is also sometimes called a dissecting microscope since it allows you to observe and work on the specimen using your fingers or tools at the same time. Stereo microscopes are typically used in botany, ecology, geology, gemology, and other sciences where specimen size is larger than a typical slide. Stereo microscopes are also used by hobbyists of all sorts - stamp collectors, coin collectors, model builders, engravers, and so on. Stereo microscopes are also widely used in industries for inspection of machine parts, circuit boards, and other assembly line products.

Benefits of Using a Stereo Microscope

Stereo microscopes offer some real advantages for beginner or a youngster since no slides or slide preparation is needed. Just send the youngsters into the backyard and allow them to collect anything their heart desires. Insects, rocks, twigs, coins - just about anything of a similar size can be viewed under a stereo microscope. This type of microscope is also much easier to operate and learn how to use. The three dimensional images produced also add a measure of excitement and interest in observing even common objects around the house.

Compound vs. Stereo Microscopes

Unlike compound microscopes, stereo microscopes provide upright and correct right-to-left images for ease of use, have lower magnifications in line with the size of specimens used, and are designed to allow the user to both observe and work on the specimen at the same time. Because they use two separate optical systems, stereo microscopes provide three dimensional images - another plus when working on a specimen. When do you select a stereo microscope? Any time you are going to examine something too large to fit on a slide or when very high magnifications are not needed, you should use a stereo microscope. Anything small enough to fit on a slide (pond water, cells) where you need high magnifications requires a compound microscope.

Make sure to check out all our Microscope How-to Guides to learn more about the different parts of a microscope and how to buy your first microscope!