The need to seriously evaluate when problems occur with your beginning microscope should be referred to professionals. If self-repair is attempted with problems that cannot be corrected by routine cleaning and adjustments, more damage can occur to your beginning microscope.
In cases of eye strains and/or headaches, try to adjust the interpupillary distance until the left and right images merge. Also modify eyepiece diopter setting by focusing the image with the right eye observing into the right eyepiece and then adjusting the diopter ring to focus the image with the left eye observing into the left eyepiece.
In case of poor image quality, the most common problem would be a dirty beginning microscope. Be sure to check if the smear is positioned correctly, not upside down. This is frequently the case when slides are used that do not have a frosted end. It can be difficult to orient the slide based on the labeling in these cases. Glass slides that are of poor quality can also be a problem but this would be constant. A common problem could also be poor quality oil. Oil should be a an equal 50/50 mixture of high and low viscosity. An aplanar lens will not give a clear image at the periphery of the field. To get a fully focused field you will need a planar lens, but this would mean increased cost. The problem can be resolved by simply moving the image to the center of the field, especially at low magnifications since at higher magnifications this is less successful. Purchasing a planar lens is needed to resolve this problem. A poor image quality will be the result if oil leaks into the objective. The only solution for this case is to change the objective. Other damage to the objective or even the condenser can occur. If KOH or other liquids touch the lens etching will occur if it is not cleaned off the scope. There is the possibility of fungal growth in the beginning microscope if this problem is not resolved with routine cleaning methods previously described.
If the condenser is not properly centered, uneven illumination occurs. To correct uneven illumination, the beginning microscope is checked for optimum illumination. If you have installed a bulb which “fits” but is not the correct size, the light may not have been properly placed for the light path of the scope. Know what bulb your scope takes and also keep an extra on hand. Fingerprints on the bulb or even silvering of a tungsten bulb can result in dark spots. By no means should you touch a light bulb with your fingers because oil from your skin will cause darkened areas in the bulb.
The most common problem for constant refocusing is the slide is not seated flat on the stage. This is usually because specimen has leaked from the slide and is causing the slide to stick when moved and it “pops” off the stage. Have the slide holder arm adjusted if there is not a problem with the slide. This is most likely the cause if you can press down on the slide and solve the problem. If this doesn’t work, you may need to have your scope recolumnized.
Many beginning microscopes flicker because the user has leaned on the cord where it enters the base of the scope and damaged the wiring. In case the wiring, rheostat or potentiometer switches are bad, stop. This is a professional level repair. Another reason for this problem could be power surges.
The items previously discussed should be checked on a daily basis. Some problems require professional repair and that professional service should be performed routinely on at least an annual basis.
