Examples
Examples
Try the starting example
- Focal length (mm)
- 50
- Extension beyond infinity focus (mm)
- 25
- Approximate magnification
- 0.5
- Image distance (mm)
- 75
- Object distance (mm, or infinity)
- 150
Try another scenario
- Focal length (mm)
- 55.00000000000001
- Extension beyond infinity focus (mm)
- 25
- Approximate magnification
- 0.454545
- Image distance (mm)
- 80
- Object distance (mm, or infinity)
- 176
Calculation method
Calculation method
Approximate magnification
Thin lens extension model: m=extension/f; v=f+extension; u=fv/(v-f).
Image distance (mm)
Thin lens extension model: m=extension/f; v=f+extension; u=fv/(v-f).
Object distance (mm, or infinity)
Thin lens extension model: m=extension/f; v=f+extension; u=fv/(v-f).
Symbols and units
- a
- Focal length (mm)
- b
- Extension beyond infinity focus (mm)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- Simple symmetrical thin-lens extension, no internal focus or pupil asymmetry. Supported limits: All required fields must be finite values of the exact declared type and within displayed bounds. Lists contain1–1000 finite numbers. JSON tables are numeric rectangular rows, at most100 rows and30 columns; individual tools have stricter shape/domain constraints. Simple symmetrical thin-lens extension, no internal focus or pupil asymmetry.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.