Agisoft Metashape
Agisoft Metashape => Camera Calibration => Topic started by: NickM on June 07, 2021, 10:56:31 PM
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Hello,
For the focal length within the camera calibration (Tools --> Camera Calibration) should the input value for this represent the focal length of my lens or the 35 mm equivalent focal length?
I.e. If I am taking photos with a 50 mm lens, should I have 50 mm for the focal length or should I have 80 mm (50 mm * 1.6; where 1.6 represents my crop factor)?
Thanks.
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NickM,
you should enter the real focal length not the 35 mm equivalent.
Following example shows case of Phantom4Pro camera that has a 8.8 mm focal length (about 24 mm in 35 mm equivalent) with a 1” Type sensor...
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Thanks Paul,
Within the Photo Pane --> Details, does the "35 mm focal" column represent the 35 mm equivalent? Should Metashape be calculating this automatically based on EXIF data? When aligning photos mine remains blank.
Nick
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yes 35 mm focal represents the 35 mm equivalent focal length...
this is read from Exif data if present... in case of Phantom4Pro the exif data contains:
---- ExifIFD ----
Exposure Time : 1/400
F Number : 5.6
Exposure Program : Program AE
ISO : 100
Exif Version : 0230
Date/Time Original : 2020:03:03 12:03:49
Create Date : 2020:03:03 12:03:49
Components Configuration : -, Cr, Cb, Y
Compressed Bits Per Pixel : 3.130994232
Shutter Speed Value : 1/400
Aperture Value : 5.6
Exposure Compensation : 0
Max Aperture Value : 2.8
Subject Distance : 0 m
Metering Mode : Center-weighted average
Light Source : Daylight
Flash : No flash function
Focal Length : 8.8 mm
Flashpix Version : 0010
Color Space : sRGB
Exif Image Width : 5472
Exif Image Height : 3648
Exposure Index : undef
File Source : Digital Camera
Scene Type : Directly photographed
Custom Rendered : Normal
Exposure Mode : Auto
White Balance : Manual
Digital Zoom Ratio : undef
Focal Length In 35mm Format : 24 mm
Scene Capture Type : Standard
Gain Control : None
Contrast : Normal
Saturation : Normal
Sharpness : Normal
Subject Distance Range : Unknown
Serial Number : 99cb05b9d3907adc8b429de0b2f2b9ec
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Thanks again, was the Exif Data summary that you provided generated in Metashape?
Regards,
Nick
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The extrct shown was taken with ExifTool