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Lens Coverage Tool

1. Choose a Camera

2. Recording Format

3. Choose a Lens

Expand or Reduce Focal Length

Camera:
{{ selectedCamera.manufacturer }} {{ selectedCamera.model }}
Sensor: {{ roundFloatTwoDecimals(selectedCamera.sensor_width) }} x {{ roundFloatTwoDecimals(selectedCamera.sensor_height) }} mm
Recording Format: {{ roundFloatTwoDecimals(selectedRecordingFormat.recordingWidth)}} x {{roundFloatTwoDecimals(selectedRecordingFormat.recordingHeight)}} mm, Image circle: {{ roundFloatTwoDecimals(selectedRecordingFormat.recordingImagecircle) }} mm

Lens:
{{ selectedSphericalPrimeLens.model }}
Image circle: {{ imagecircle==0 ? 'unknown' : imagecircle + ' mm' }}

Lens:
{{ selectedSphericalZoomLens.model }}
Image circle: {{ imagecircle==0 ? 'unknown' : imagecircle + ' mm' }}

Lens:
{{ selectedAnamorphicZoomLens.model }}
Image circle: {{ imagecircle==0 ? 'unknown' : imagecircle + ' mm' }}

Lens:
{{ selectedAnamorphicPrimeLens.model }}
Image circle: {{ imagecircle==0 ? 'unknown' : imagecircle + ' mm' }}

Lens:
{{ selectedPhotoPrimeLens.model }}
Image circle: {{ imagecircle==0 ? 'unknown' : imagecircle + ' mm' }}

Lens:
{{ selectedPhotoZoomLens.model }}
Image circle: {{ imagecircle==0 ? 'unknown' : imagecircle + ' mm' }}

Expander/Reducer:
{{ selectedFocalExpandersReducers.name }}
{{ selectedFocalExpandersReducers.factor > 1 ? 'expands' : 'reduces' }} Lens Image circle to: {{ imagecircleAfterFocalLengthModification }} mm

MOBILE DEVICE: Graphical representation of lens coverage is disabled on smaller screens because an accurate overlay can't be displayed.
Just check if the image circle of the lens is larger or equal to the image circle of the chosen recording format.

Explanation:

If the color of the circle (represents the lens image circle) is green you get sufficient corner-to-corner illumination on the sensor (represented by the blue rectangle) which should be aimed for for optimal picture.

Should the circle color turn orange the image circle of the lens does not (fully) cover the sensor and as a result you might see vignetting (darkening around the edges) or even portholing (blackness in the corners) may occur.

When using zoom lenses the image circle at wider focal lengths is usually smaller than at longer focal lengths. Some lenses might cover the entire sensor at the long end but could introduce vignetting at the wide end.

Manufacturers of Photo Lenses rarely publish or share the image circle of their lenses. They commonly indicate coverage of "35mm" or "APS-C" sensors and therefor a generic value will be calculated and displayed above.

Depending on the chosen recording format, a smaller area of the camera sensor might be recorded. This is factored in when viewing the graphical representation above.

This tool DOES NOT indicate if the chosen lens can physically be mounted on the selected camera. Please ensure that you use the correct lens mount or adapter!

Despite the theoretical data from this tool it is highly recommended to test your desired lens and camera combination before filming! PREP IS KEY