microscopesafari.com - Microscope Safari - Journey to the Unseen World - Wet Mount Slides

Microscope Safari
Tips and Tricks While Using the Microscope

Back to Home Page

Get Comfortable

Place the scope on a table so that you don't have to lean over to reach the eyepiece(s). Place it squarely on the table and far enough from the edge to ensure a comfortable area to place your arms while using the focus and stage tracking knobs.

Keep your head and spine straight, not hunched over. A height-adjustable chair is recommended for adjusting the chair for proper back alignment while viewing.

Get the Most out of Your Glass Slides

Instead of frosted slides, use plain glass slides. Place a drop of culture water on either side of center and apply the cover slip. When finished observing this wet mount, place another drop on the other side of center and place another cover slip. This way a slide may be used twice. If using small cover slips, you may be able to fit three sample drops on the same slide.

Glass slide

Keep the Slides and Cover Slips Clean

Slides and cover slips must be kept clean. Keep them in the box they came in until you need to extract one. Never touch the surface of slides or cover slips - manage them by the edges only. It is difficult for the enthusiast to avoid some dust, or fibers creeping onto the glass surfaces.

If possible, do not reuse slides or cover slips. Trying to clean them can leave too many microscopic artifacts behind and broken slips. As cheap as slides and cover slips are, it is hardly worth the time to clean them for reuse.

Make sure to dispose of used slides and cover slips properly. Wrap them in paper and tape them like a little gift package.

Use a Vacuum Sucking Pen Tool

Vacuum pen tool

Using fingers to extract thin glass cover slips from their box can lead to grabbing too many and spilling some onto the table, breakage or contaminating the surfaces. This is especially true for #1 glass slides.

A vacuum sucking pen with an angled nozzle makes it easy to extract cover slips from their container. The tool has a flexible bladder to enable the suction and the broad suction header that presses against the cover slip. When the bladder is released, the suction holds a firm grip on the glass surface until you drop it onto the slide.

A vacuum may exist between glass slips making them difficult to separate. The vacuum pen will hold one until the other falls back into the box.

Removing Grit from Your Sample

Grit in a drop of water can be large enough to prevent the cover slip from seating properly. If one edge of the cover slip is too high, it will prevent higher power objectives from swinging into place. Worse, the lens of the objective could get wet.

When a sample involving soil or bottom muck is first collected, let it stand for a day or two. Then stir it up to suspend the lighter material and organic debris while letting the heavier grit settle. Pour the sample into another container slowly leaving the grit on the bottom of the first container. Before the sample is completely emptied into the second jar, swirl it again for the same effect. Done properly, this works very well.

Collecting Samples is a Shock to Ptotozoans and Invertebrates.

When you first collect a sample from ponds, streams, lakes or water-filled dirtches, microscopic creatures need to adjust to their new environment. Give them a day or two to settle down at room temperature. Samples collected from cold environments may take longer.

You Are Disappointed With Your Sample Even Though There is Plenty of Debris.

Samples that contain some muck from the bottom reveal a cornucopia of single-celled life and many invertebrates. But where are they under the microscope?

Scanning slides for life may be fruitful in the first drop during the spring and summer, or seemingly devoid in samples collected during cooler temperatures.

When a mounted sample shows only sparse life, scan it again. It's likely there will be more genera the second time. Fast swimming life tends to miss the small circle of light in light microscopy on the first scan. Life that is hiding under debris will reveal itself. It's a good idea to do this a few times.

Microscopic Subject Racing Around Too Fast

After preparing a new slide, protists and invertebrates may be agitated and in search for a new comfortable food source. Patience is necessary until your subject slows. The water under the cover slip will eventually start to dry and withdraw from the edges. Oxygen is depleted as this happens and the debris starts to clump at the sides. If the subject has not been slowed by now, it will become corralled by the debris.

Microscopic Subject Hiding Under Debris

Protists are drawn to debris to feed. This often involves slipping under the debris and staying there. One way to nudge them out for better viewing is gently tapping the cover glass with a toothpick to agitate the debris.

The Use of Racking Focus

The use of racking focus, or focusing up and down, while viewing slow or stationary objects brings different details into view - like an MRI.

Changing Magnification Power

See Microscope Recommendations and Magnification.

While scanning slides looking for life, use a lower power such as 100X or 200x viewing magnification to find the protozoa. For larger protozoa this may be all that is needed. Since some protozoa swim around too quickly to reliably view, try to follow them with a lower magnification until they come to rest or feed in some debris. Then rotate the turret to a higher magnification to view the details. Magnifications higher than 1000X are not really necessary for the amateur for protozoa study.

Keep Dust Away from the Microscope

Dust and grime are the microscope's enemy. Covering the microscope will help keep the eyepieces and objective lenses clean.

No need for a custom dust cover - in most cases a 2.5-gallon Zip Lock storage bag will cover the working parts of a microscope. Commercial dust covers are deeper and do a better job.

Never take the microscope apart. If dust gets inside the body, it is near impossible to clean it out. When changing out the eyepieces, do it quickly, preferably under a clear plastic bag. If an objective lens needs changing or cleaning, plug the hole in the nose-piece with the supplied cap.

Slowing Microscopic Life With Chemicals

There are many chemical formulas for slowing microscopic life. The chemistry is left to those who pursue it.

Premixed formulas are limited to a few. Experimentation with how much of each slowing agent to use is up to the individual. A rule of thumb is the more you use, the faster the protists die off.

The effects of quieting agents varies from organism to organism. Practice with different solutions to get a feel for how long the organisms stay alive before they expire.

One advantage to having the protists die before your eyes is the opportunity to view or film their details before they leak out and distort.

Some protozoans may distort by bloating when using slowing agents.

Recommendations are:

Ward's Detain Protist Slowing Agent - Not toxic to the organisms but may cause some to behave erratically.

Methyl-cellulose - Toxic to life under the cover slip. Experiment with amounts.

Carolina Protoslo Quieting Solution - Eventually toxic to the protists. larger ciliates soon tend to behave erratically.



Back to Home Page









Copyright 2017 Steve Cunningham, Baltimore, MD