BestScopes.com - Quick Microscope Education

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Quick Microscope Education

BestScopes.com only sells the best!

When we went looking for a microscope several years ago, we had several criteria in mind -- durability, wide-field eyepieces, fine optics, easy focusing, a good warranty, and an affordable price. After several dissatisfying experiences with cheap "toy" microscopes, we did not want to make another mistake! We asked an acquaintance (who serviced microscopes for the schools and industries in our region) which brand of scope we should purchase. He said that, out of all the manufacturers' scopes he repaired, he never had to fix the ones from LW Scientific since they were so well-made and had a lifetime warranty! He was right. We've been delighted with our scopes and so have our customers! We're providing you with the best product possible! We don't want you to make a mistake that could cost you -- so read further and educate yourself!

What's the difference between a compound microscope and a stereoscope?

A compound microscope is just the standard name for a scope used for viewing slides. It can have one (monocular) or two (binocular) eyepieces; however, it enlarges the image through only one objective at a time. Compounds are perfect for working at high powers of magnification.

A stereo microscope or stereoscope is really a pair of microscopes -- one for each eye that enables you to see objects in their true three-dimensional form. In other words, it is a high-powered magnifying glass! A true stereoscope will always have two eyepieces (binocular) with matching objectives for each eye. Slides are generally not used with a stereoscope (but can be) because of its lower magnification than a compound. It's certainly our family's favorite microscope!

How does a microscope make things look bigger?

Man naturally discovered that when you observe anything through a drop of water, it appeared larger.

A drop of water is dome-shaped or convex -- wider in the middle and thinner toward the edges. It is a lens.

As a light ray enters and travels through the drop of water (which is denser than air), it travels at a slower speed. When this light ray exits back up out of the drop and hits the air, it bends (refracts) and speeds up. This bending is what enlarges the image.

In a compound microscope there are two convex lenses (the eyepiece and the objective lens) working together to greatly magnify the image.

Part of searching for the right microscope is understanding the terminology and anatomy. Quickly read through the next section and you'll be able to make the best choice for your needs.

Basic Microscope Anatomy

As we take our "tour" of the microscope, you'll want to refer to this diagram so you'll understand what part we'll be discussing.

Microscope Anatomy Diagram

Diagram courtesy of LW Scientific, Atlanta, GA

All of BestScopes.com's fine instruments are made of a heavy-duty metal alloys for durability and stability. These are scopes that are so stable that even when used on a wiggly table, you won't see the specimen vibrating through the eyepiece! (Great for kids!) All of our scopes come in an acid and reagent resistant finish!

Fine Optics

The most important thing in looking for a microscope is fine optics, or lenses. You want everything to look brilliant and clear. All of BestScopes.com's lenses are DIN threaded (DIN stands for Deutsche Industrie Norm). This international standard insures compatibility with lenses from any microscope manufacturer in the world. Our DIN lenses assure you that your scope will not become obsolete in the future should you ever have to replace a lens. Since you can't actually look through our scopes over the Internet, we'll guarantee our optical quality with a 60-Day Money Back Guarantee on all our scopes! (Not to mention the manufacturer's Lifetime Warranty!) All our lenses are achromatic, which means flatness of field or how clear your field of view is from edge to edge.

Eyepieces:

The lens that is closest to your eye when looking through any microscope is called the eyepiece or the ocular. All of BestScopes.com's eyepieces are wide-angle lenses (which means they're as big as a dime) so even the smallest child can enjoy the view without squinting! Binocular microscopes have two eyepieces -- one for each eye. Monocular microscopes have one eyepiece. The eyepiece is labeled with its magnification (power), such as 10x, meaning it enlarges the image 10 times. A Seidentopf binocular head is a BestScopes.com standard which means the eyepieces smoothly twist for interpupillary (distance between the eyes) adjustment as opposed to the inferior sliding head.

Objective Lenses:

These are the lower cylindrical lenses on a microscope that are closest to the specimen being viewed. They can be added or removed by threading (by hand) in or out of a revolving nosepiece. All of BestScopes.com's nosepieces have room for four objectives! Objectives come in different magnifications (powers) and actual lengths. Longer objectives have higher power while shorter ones have lower power. All our scopes have color-coded achromatic objectives for easy, quick identification! Our stereoscopes have a matching pair of objectives (one for each eyepiece).

Magnification:

If you multiply the power of the eyepiece lens (10x) by the power of the objective lens (say 40x), you'll have what is called the magnification (400x). In other words, your specimen will look 400 times larger than it actually is. You'll notice that our basic compounds have magnifications of 40x, 100x, 400x, and some even have 1000x. If you want higher magnifications, you'll want one of our Revelation scopes. They each include an extra pair of 16x eyepieces which will increase your magnification to 64x, 160x, 640x, and 1600x!

Focus:

Probably the most important thing to look for in a microscope is its ability to get an image into perfect resolution or focus -- and stay that way. BestScopes.com offers you clear focusing that will make your time spent with your microscope enjoyable and satisfying. With our scopes your children will be stimulated (instead of being frustrated) towards more creativity in their scientific studies when they can easily focus on an image.

All microscopes have a coarse focus knob that brings the specimen into perfect focus very quickly. For families with young children this may be all you will need. However, when working at higher magnifications a fine focus knob is necessary so that the depth or thickness of a specimen will appear sharp and clear. We highly recommend any of our Observer or Revelation scopes as they all have both the coarse and fine focus knobs.

All our scopes have two more very important focusing features you won't want to be without -- a slip clutch, and parfocal ability. A slip clutch (a "notched" system that the microscope's stage "rides" on) keeps the stage from "slipping" so you can keep perfect focus. Parfocal means the object in view will stay in focus when you rotate (change) the objectives! Pretty neat, huh?

Lighting:

Remember the microscopes from the old days? They either had a mirror (for reflecting light onto the specimen) or a little tungsten light bulb that heated up and killed your pond specimens! In your search for a microscope, get the best lighting possible and avoid frustration! First of all, avoid any scope with tungsten (incandescent) lighting because they cast a hot, yellowish, and very unnatural light on your specimen. BestScopes.com provides you with fluorescent lighting on all our student scopes and halogen lighting on our professional scopes.

Fluorescent lighting is best because it's low cost (it produces three times as much light as tungsten!), cool (which will keep your specimens alive), and it casts a natural white light which is very easy on the eye! Objects actually look more brilliant under fluorescent lighting! All of our fluorescent and halogen bulbs can easily be replaced with bulbs from your nearest home center!

Halogen lighting is found on all our Revelation microscopes. It provides a very natural white light and does have some heat output. This is the standard light in the medical and research industry. Luckily, our scopes with halogen lights also have variable light adjustment from 0-20 watts, which greatly decreases the heat.

What's an Iris Diaphragm?

Working like the iris on an eye, the iris diaphragm is a device on the underside of the stage that opens and closes with a simple lever, thus controlling the amount of light that passes through the specimen. All of our scopes have this superior type of diaphragm (as opposed to a disk diaphragm), which will enable you to control the light to any setting you desire to let you see each specimen at its best!

What's an Abbe Condenser?

The condenser is a lens on the underside of the stage that condenses and focuses the light after it comes through the iris diaphragm. An "Abbe" is the standard for moveable condensers which give you greater light control at very high magnifications. All our scopes have the moveable Abbe condenser, with the exception of the Explorer II which has a fixed (non-moveable) condenser.

What's a Mechanical Stage?

A mechanical stage is a device that you attach on top of your existing stage that holds the slide firmly and allows you to move it precisely (most valuable at 400x or more where precision is critical), without ever having to touch it with your fingers! It's a great option if you have children, especially since their fingers aren't as agile. All of our student scopes are pre-drilled to accept this mechanical stage whenever you need one. The mechanical stage is a standard feature on all our Revelation microscopes.

Remember, ALL our Best Scopes have...

a Lifetime Warranty (and a 60-Day Money Back Guarantee!)
heavy metal acid-resistant finish
fine achromatic DIN-threaded optics
cool fluorescent & halogen illumination
360° rotating eyepieces! / 45° inclined tubes
wide-field eyepieces
rotating quadruple nosepieces
slip-clutch focusing
adjustable stage stop
and more!

Glossary

Part of searching for the right scope is understanding the terminology and anatomy of a microscope. Quickly read through this section and you should be able to make a best choice for your needs.

Eyepiece: The lens closest to your eye when you look through a microscope or stereoscope.

Body Tube: The cylindrical tube that holds the eyepiece.

Arm: The curved part that holds the body tube in place over the stage.

Objectives: The lower cylindrical lenses on a microscope or stereoscope that are closest to the specimen being viewed.

Magnification: Multiply the power of the eyepiece lens (10x) by the power of the objective lens (40x) and you get the magnification (400x).

DIN Objectives: (Stands for Deutsche Industrie Normen) A DIN-threaded lens is an international standard which insures compatibility with lenses from any microscope manufacturer in the world.

Stage: The flat surface you put your slide or specimen on.

Stage Clips: The metal clips that hold the slide or specimen stationary.

Mechanical (Moveable Stage): A device you attach to your stage that holds the slide firmly and allows you to move it precisely (most valuable at 400x or more where precision is critical).

Coarse Focus Knob: Used to roughly adjust the position of the body tube, which quickly brings your specimen into focus.

Fine Focus Knob: Used to make adjustments to the body tube, bringing your specimen into more fine focus. We highly recommend a fine focus for most scientific study.

Slip Clutch: Keeps the stage from "slipping" so that you can focus perfectly!

Parcentered: When the object in the center of your viewing area stays centered when you rotate (change) objectives.

Parfocal: When the object in view stays in focus when you rotate (change) objectives.

Iris Diaphragm: Working like the iris on an eye, this device is on the underside of the stage. It adjusts (by opening and closing) the amount of light that passes through the specimen.

Abbe Condenser: A device on the underside of the stage that condenses and focuses the light coming through the diaphragm. A moveable condenser is adjustable, whereas a non-moveable has a fixed light focus. A condenser is most valuable at 1000x or higher.

Interpupillary Adjustment: The ability to adjust the spacing between the two eyepieces on a binocular microscope so it fits a person's interpupillary distance comfortably. The Seidentopf head allows for the best adjustment by just twisting the eyepieces.

Oil Immersion: A lens that requires a drop of special oil on the specimen for use. The oil is put on the cover slip, and the objective is actually lowered into the oil. Oil immersion lenses are sealed so they won't be damaged by the oil. Never lower a non-oil immersion lens into the oil. Our Observer IV and Revelation lines both have a 100x oil immersion lens.

Illumination: The light source, either natural or artificial, at the base of the microscope. All our illuminated microscopes are a cool fluorescent or halogen type which is safest for your specimens. (Regular tungsten lighting would create too much heat and kill some organisms!)