Using a Bright Field Light Microscope
Strategy for Working up in Magnification
Unless you are so familiar with a type of specimen that you can go straight to an appropriate magnification and find your target immediately, it is best to take the same approach to finding specimens each time you observe. The most consistently effective strategy is to start at low magnification, find the target, adjust illumination, resolution and contrast, focus and center the object, and then raise magnification. Most sets of objective lenses are parfocal, meaning that the objectives are matched, so that if a specimen is in focus using one objective, it will be very nearly in focus when you raise the magnification using the next objective lens. Thus, if you re-focus, using only the fine focus control, and center the target each time you change magnification, you should have no trouble obtaining the image you seek at the desired final magnification.
After reaching 100x magnification, it is a good to re-adjust the microscope for binocular viewing, if you have a binocular eyepiece tube. You can see more detail now, and the better the oculars are adjusted to match your eyes, the more satisfactory the viewing.
- Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K., & Walter, P. (2002). Molecular biology of the cell (4th ed.). New York: Garland Science.
- Caprette, D. (2005). Light microscopy. Retrieved 09-12-2005 from http://www.ruf.rice.edu/~bioslabs/methods/microscopy/microscopy.html
- Lodish, H., Berk, A., Zipursky, L., Matsudaira, P., Baltimore, D., & Darnell, J. (2000). Molecular cell biology (4th ed.). New York: W.H. Freeman and Co.
- Nave, C.R. (2005). Hyperphysics (light and vision). Retrieved 09-12-2005 from http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
- Wolfe, S.L. (1993). Molecular and cellular biology. Belmont, CA: Wadsworth Publishing Company.
- Caprette, D. (2005). Microscope slide images.
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