Mastering
Microscopy Skills
Essential techniques for biology students.
by Kris Sherdley
Calculating Magnification
Ocular Lens
1
Typically 10x magnification.
Objective Lens
2
Varies: 4x, 10x, 40x, 100x.
Total Magnification
3
Multiply ocular by objective lens magnification.
Focusing the Microscope
1
Coarse Focus
Use low power, adjust until image appears.
2
Fine Focus
Slowly turn fine adjustment knob for clarity.
3
Higher Magnification
Switch objectives, refocus using only fine adjustment.
Preparing Wet Mounts
Clean Slide
Use glass slide and coverslip.
Add Sample
Place specimen in water droplet.
Apply Stain
Add dye for contrast if needed.
Cover
Gently lower coverslip to avoid bubbles.
Drawing Microscopic
Structures
1
Sharp Lines
Use fine-tipped pen for clear outlines.
2
Accurate Proportions
Maintain relative sizes of cell components.
3
Straight Labels
Use ruler for neat, horizontal label lines.
4
Detail
Include key structures visible at magnification.
Measuring Field of View
Low Power
Calculate Higher Powers
Applications
Use ruler on slide to measure diameter.
Divide low power by magnification
Estimate specimen size using field
increase.
diameter.
Working with Micrographs
Magnification
Actual Size
Image Size
M=I/A
A=I/M
I=M×A
Use formulas to calculate unknown values.
Quantitative vs. Qualitative
Observations
Quantitative
Measurable data: size, count, time.
Qualitative
Descriptive observations: color, shape, texture.
Balance
Both types crucial for comprehensive analysis.