Start here · Essential guide
Magnification vs Resolution in Microscopy
Magnification makes a specimen look bigger; resolution decides how much detail you can actually see. Learn how they differ, what limits each, and why it matters.
How Microscopes Work
Magnification and Resolution
How to calculate total magnification, why resolution and numerical aperture set the real limit, and how to measure specimens.
Depth of Field and Focal Length in Microscopes
Why depth of field shrinks at higher power, approximate figures for each objective, what focal length means for objectives and eyepieces, and how it sets magnification.
Digital Microscope Magnification Claims: What "1000x" Really Means
Is 1000x on a cheap digital microscope real? Learn how on-screen magnification is calculated, why it isn't lab-microscope 1000x, and which specs actually matter.
Empty Magnification: Why More Power Doesn't Always Show More Detail
Empty magnification makes the image bigger without showing new detail. Learn why it happens, the 500–1000 × NA rule, and how to pick eyepieces that avoid it.
How to Calculate Total Magnification on a Microscope
Total magnification is eyepiece power times objective power. See the formula, a table for 4x to 100x objectives, the biology image-size formula and unit conversions.
How to find the total magnification of a compound microscope?
To find total magnification, read the eyepiece and objective markings, check for any extra factor, and multiply. A step-by-step routine with worked examples.
How to Measure Specimens With an Eyepiece Reticle and Stage Micrometer
Calibrate an eyepiece reticle against a stage micrometer for each objective, then measure cells and other specimens in micrometres. Step-by-step, with worked examples.
Microscope Field of View: Formula and How to Measure It
Field of view = field number / objective magnification. Get a reference table for common eyepieces, learn to measure FOV with a ruler and estimate specimen size.
Numerical Aperture Explained: The Number That Limits Your Microscope
Numerical aperture (NA = n sin θ) measures how much light an objective collects. Learn how it sets resolution, why oil raises it, and how to read it on your objectives.
Resolution and Resolving Power of Light Microscopes
What resolution and resolving power mean, the Rayleigh and Abbe formulas, how to estimate your microscope's limit, and practical ways to see finer detail.
What is magnification?
Magnification is how much larger an image appears than the real object, written as a ratio such as 10x. Learn the formula, linear vs angular types, and how microscopes use it.
What is the formula for magnification of a simple microscope?
The magnification of a simple microscope is M = 1 + D/f with the image at the near point, or M = D/f for a relaxed eye, where D is about 25 cm. Worked examples inside.
Why is the total magnification 400x when using a 40x objective?
A 40x objective gives 400x because a standard 10x eyepiece enlarges the objective's 40x image ten times more. Here's why the two numbers multiply.
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