FocalCrop Pro

Camera Sensor Crop Factor & Lens Equivalence Calculator

Optics & Cinematography

Sensor Crop Factor & Lens Equivalence

Determine true 35mm full-frame equivalent focal length, depth-of-field aperture equivalence, angle of view, and hyperfocal distance across any digital camera sensor.

Camera Optics Compare prime and zoom lenses, sensor-mount adapters, circular polarizers, and professional cinema cameras.

Lens & Sensor Specifications

mm
Common Lenses:

📐 Physical Dimensions

Sensor Area 368 mm² 42.6% of Full Frame
Crop Factor 1.52x Diagonal multiplier
35mm Equivalent Focal 53.2 mm Standard Normal View
Equivalent Aperture (DoF) f/2.1 Full-Frame Bokeh Match
Diagonal Field of View 44.1° Angle of View (AoV)

🖵 Interactive Viewfinder Framing Comparison

Full Frame (Outer) vs Selected Sensor (Orange Box)
APS-C (1.52x Crop)

Angle of View & Hyperfocal Distance

Horizontal AoV 37.3°
Vertical AoV 25.1°
Hyperfocal (Sharpness) 43.8 m

Demystifying Crop Factor, Exposure & Depth of Field

1. The Exposure Paradox

A common misconception among photographers is that crop factor "steals light." It does not affect exposure!

An f/2.8 lens projects the exact same brightness per square millimeter of sensor surface regardless of whether it is attached to a Medium Format Hasselblad, a Full Frame Sony, or a Micro Four Thirds Panasonic. Your shutter speed and ISO settings remain identical.

2. The Depth of Field Equivalence

However, crop factor does impact background separation (bokeh blur) and depth of field:

Equivalent Focal = Physical Focal * Crop Factor
Equivalent Aperture = Physical Aperture * Crop Factor

To achieve the identical framing and bokeh of a Full Frame 50mm f/1.4 on an APS-C camera, you must use a 33mm f/0.95 lens.

Frequently Asked Questions

What is Hyperfocal Distance?

Hyperfocal distance is the focus distance that produces the maximum depth of field, extending from half of the hyperfocal distance all the way to infinity. Landscape and street photographers set their focus ring to the hyperfocal distance to ensure everything from foreground rocks to distant mountain horizons remains tack-sharp.

What is a Speed Booster (Focal Reducer)?

A Speed Booster (optical focal reducer) is an optical adapter mounted between a full-frame lens and a crop-sensor camera body (APS-C or Micro Four Thirds). It concentrates the larger full-frame image circle down to fit the smaller sensor, effectively reducing focal length by 0.71x while increasing lens transmission by 1 full stop (turning an f/2.8 lens into an f/2.0).

Why is 35mm consider the universal standard for focal length?

35mm film (with an image frame size of 36mm x 24mm) was standardized by Oskar Barnack for the original Leica camera in 1913 and became the dominant global photographic format throughout the 20th century. Modern "full-frame" digital sensors match this exact physical size, making it the industry benchmark for lens angle comparisons.