Focal Length Sensor Size Calculator

Focal Length Equation:

\[ FL_{eq} = FL \times \text{Crop Factor} \]

Equivalent Focal Length (FL_eq):

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1. What is the Focal Length Equation?

The Focal Length Equation calculates the equivalent focal length for different sensor sizes by multiplying the actual focal length by the crop factor. This helps photographers understand how lenses will perform on cameras with different sensor sizes compared to full-frame sensors.

2. How Does the Calculator Work?

The calculator uses the focal length equation:

\[ FL_{eq} = FL \times \text{Crop Factor} \]

Where:

\( FL \) — Actual focal length of the lens (mm)
\( \text{Crop Factor} \) — Sensor crop factor (dimensionless)
\( FL_{eq} \) — Equivalent focal length on full-frame sensor (mm)

Explanation: The equation converts the focal length to its full-frame equivalent, allowing photographers to compare field of view across different camera systems.

3. Importance of Focal Length Calculation

Details: Understanding equivalent focal length is crucial for photographers working with multiple camera systems, as it helps maintain consistent framing and field of view across different equipment.

4. Using the Calculator

Tips: Enter the actual focal length of your lens in millimeters and the crop factor of your camera sensor. Common crop factors: APS-C (1.5-1.6x), Micro Four Thirds (2x), Full-frame (1x).

5. Frequently Asked Questions (FAQ)

Q1: What is crop factor?
A: Crop factor is the ratio of a camera sensor's size compared to a full-frame (35mm) sensor. It indicates how much the image is "cropped" compared to full-frame.

Q2: Does this affect aperture?
A: No, the crop factor only affects field of view, not aperture. The f-stop value remains the same regardless of sensor size.

Q3: Why is full-frame used as reference?
A: Full-frame (35mm) has been the standard in photography for decades, making it a convenient reference point for comparing lenses across different systems.

Q4: Does this calculation affect image quality?
A: No, it only helps understand field of view equivalence. Image quality depends on the lens optics, sensor technology, and other factors.

Q5: Can I use this for video cameras?
A: Yes, the same principle applies to video cameras with different sensor sizes. The calculation helps maintain consistent framing across different camera systems.