Common Sense Tips On Using A Field Microscope

Field-Microscopes are compact, portable optical microscopy. These are built as lighter versions of most standard microscopes but are designed to be durable and sturdy, to make the instrument easy to carry, transport and use during field studies. Although they are smaller, Field-Microscopes have the same functionality as traditional microscopes. Here are a few simple steps on how to use a basic field microscope:

Things to prepare before using your field microscope
Find a good location on which to place your field microscope. Use a flat, sturdy, solid surface to ensure that the field microscope is secure. An uneven surface can cause either the microscope or the slide to slip.

Illumination

Before mounting the specimen onto the field microscope, make sure the source of light is already established. In some cases, you might need to use the sun as a source of illumination, so find a good location for the microscope. Otherwise, use the battery powered light source on your field microscope.

Preparing the slide

Once the field microscope is ready, begin preparing the specimen. Here is where different slide preparations come in. Some of the most common Field-Microscopes are metallurgical and petrographic microscopes, those used to examine metals, rocks and minerals. How you want to view your specimen will depend on what type of material or sample you have (live organisms, stained samples or natural, solid, larger samples such as fossils and rocks) and how the material will handle light. Opaque materials will not let light through but will be very good at bouncing it back while other materials, such as translucent and transparent materials, will allow light to pass through.

For opaque materials, most types of lighting used are sourced from the top of the specimen. This type of light will bounce off the specimen and pass through the objective lens. What you will see through the lens will be the reflected image. Translucent and transparent materials often require lighting substage, or located underneath the specimen mount.

Using a field microscopy technique

There are also other types of microscopy techniques used with Field-Microscopes that will affect the image that you will view. Transmitted lighting, bright field, dark field, incident lighting and polarized lighting are just some of the few. Some Field-Microscopes are inverted microscopes, used with larger, heavier specimens. Know what type of field microscope you have so you will know what its main uses and limitations are. You will also know how to prepare your specimen sample if you understand what the microscopy technique is.

Mounting the specimen

Cut, slice or polish your specimen if necessary, although some materials may also be viewed whole. The field microscope is often equipped with stage clips that hold the glass slide in place. If you have a prepared slide, use these clips to secure your specimen. Otherwise, ensure that the sample material is sitting securely on the stage.

Using your field microscope

Now that the specimen is mounted, begin choosing which magnification power to use. With magnifications, the higher the number, the more details you’ll be able to see. Always begin with the lowest magnification power on your field microscope. You can do this by turning the objective lens to choose which one gives the best view. Use a higher magnification power if the lower magnification power is insufficient to produce an effective image. Sometimes, it’s also a matter of field-of-view so choose what is most comfortable or necessary.

You might also want to experiment with higher power eyepieces. Simply remove the eyepiece from the instrument and replace it with one that offers a higher magnification. The number on the eyepiece multiplied by the power of the objective lens is the total magnification or enlargement of the specimen’s image. This is sometimes done if you can go no further with the magnification power of your objective lens.

When using the objective lens, make sure there is enough working distance between the lens and the specimen. One of the most common accidents involving microscopes is pushing the objective lens so low that it touches the specimen or breaks the glass slide.

Focusing

You will often need to refine the image your field microscope produces. Use the coarse focus first, especially if you’ll be using a low magnification power. Use the fine focus to refine the image or when you’re using a higher magnification power.

Cleaning and transport of Field-Microscopes

Using the field microscope outdoors will expose it to dust, dirt, sand, moisture, even mud. If this happens, make sure that the field microscope you’re using is cleaned after use or before storage. Don’t wait until the dirt accumulates or hardens before wiping the microscope clean.

Use a clean, soft cloth to wipe the metal and plastic parts of the instrument. With the sensitive lenses, use a lens cloth. A cleaning special solution formulated for lenses and glass. Avoid using strong solutions such as ammonia mixes and alcohol because these can damage the lens. When transporting your field microscope after use, keep it in its own carrying case.