MCB2004L Microscopy

My eyes are tired while using the microscope. What is the possible cause and solution?

- possible cause: Eye piece tubes may not be adjusted correctly - solution: Adjust eye piece tubes (set vernier on zero)

There is not enough light to see my stained slide. What is the possible cause and solution?

- possible cause: The diaphragm may be closed or condenser is in down position. - solution: Check condenser and diaphragm (open as needed)

My field of view on the microscope is not complete or there is darkness or uneven brightness at periphery. What is the possible cause and solution?

- possible cause: The objective may not be completely in place. - Solution: Be sure objective has clicked into place.

I can't focus my microscope on l00X oil. What is the possible cause and solution?

- possible cause: There is no oil or not enough oil on the slide or there is dirt on the lenses - solution: Add oil and clean objective and eye pieces

I cannot get sharp focus on high-dry (40x). What is my possible cause and solution?

- possible cause: There is oil or other material on the outside of the objective; there is Dirt or dust on lens; or the diaphragm may be too open - solution: Clean objective and lens; Adjust diaphragm

I can't focus my microscope under low power with coarse adjustment. What is the possible cause and solution?

- possible cause: the fine focusing knob may be turned too far - solution: Turn fine focusing knob to one end point, turn back to next endpoint counting number of turns. Then turn back to halfway point.

I Can't find material on the slide or focus on l00X but could on lower powers. What is the possible cause and solution?

- possible cause: the slide may be upside down or you may need to center fine focusing knob - solution: Carefully blot oil from this side of slide and turn it over

My wet slide material is foggy or cannot be seen. What is the possible cause and solution?

- possible cause: there may be too much light - solution: Turn down light source and check iris diaphragm

I cannot see any material on my slide. What is the possible cause and solution?

- possible cause: too little material - solution: Make a mark with a sharpie on the upper surface of the slide. Locate it and focus on the low power. Then, without adjusting the focus, move the stage so that the material you want to observe is in the center of the view.

The low dry objective lens has a magnification of...

10x

The high dry objective lens has a magnification of...

40x

The scanning power objective has a magnification of...

4x

How should you transport a microscope?

Always carry the microscope by the base and the arm using two hands, and transport it in an upright position. Never pick it up with one only hand.

If you can focus your slide on the lower powers, but are unable to focus under the higher powers (40x and oil), one likely reason is: A. The light is too bright B. The ocular is dirty C. The slide is upside-down D. The condenser is not focused

C. The slide is upside-down

When should you clean microscope lenses and what do you clean the lenses with?

Clean the lenses before using the microscope and after use. You can also clean the lens if the image is unclear under the microscope. Clean all the lenses with lens paper and lens cleaner, and then use the lens paper to dry and avoid streaks.

ocular lens

Eyepiece of a microscope

How do you focus a light microscope?

Focus by placing the lowest power lens, over the object to be viewed. Use the coarse focusing knob to place the stage in the position closest to the sample. Now, look through the oculars and back the stage down, using the coarse focusing knob, until something begins to become visible. Change to the fine focusing knob and bring the object into focus. Once you have found an object on low power, have it in focus and have it centered, and then witch over to the next power lens. Then repeat.

fine focusing knob

Focusing the image to fine detail. Used when working with the high dry (40X) and oil objectives (100X)

Objective lens

enlarges the image of the specimen

Condenser

focuses light through the specimen

Diaphragm

located at the base of the condenser and limits the amount of light that enters the condenser

How to calculate magnification

ocular magnification x objective magnification

Stage

supports the slide being observed

Two reasons why you should clean your microscope before and after use are..

to remove oil from the oil emersion lens and to remove any harmful "material" from the ocular lens