Extension Tube Magnification Gain
A simple lens model estimates additional magnification from added extension.
Extension Tube Magnification Gain
Optics · 2 inputs
How to use this calculator
- Enter extension length in mm.
- Enter focal length in mm.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Keep capture settings, physical dimensions and delivery requirements in separate columns of the job notes. A mathematically equivalent setting may change motion blur, depth of field or noise. Check an actual frame before committing an entire session to a numerical estimate.
Internal focusing and existing close-focus extension make the real result lens-dependent.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.
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