Agisoft Metashape

Agisoft Metashape => Camera Calibration => Topic started by: flyzk on January 27, 2023, 08:49:22 PM

Title: Multispectral calibration
Post by: flyzk on January 27, 2023, 08:49:22 PM

in case of multispectral processing, does the camera settings that affect exposure (iso, shutterspeed, aperture) are taken into account during calucation of radiometric value ?
- in case of using DLS ?
- in case of not using DLS ? example : if exposure of the image changes with the same  DLS value but with a different exposure camera setting (iso, shutter, aperture), will the radiometric value be the same?
- in case of using DLS + calibration mire ?

Does it depend of the camera used?



thanks

Title: Re: Multispectral calibration
Post by: nprokofyev on February 14, 2023, 03:25:43 PM

Yes, yes and yes.

- example : if exposure of the image changes with the same  DLS value but with a different exposure camera setting (iso, shutter, aperture), will the radiometric value be the same?
- yes, to the precision of (mostly DLS) data

Does it depend of the camera used?
- It may, if camera writes some incorrect metadata. But generally it's highly unlikely.

Title: Re: Multispectral calibration
Post by: flyzk on February 21, 2023, 12:19:44 AM

Hello,
And thanks for your answer !

By reading your answer I realized my question was not clear  ;D

if exposure of the image changes with the same  DLS value but with a different exposure camera setting (iso, shutter, aperture), will the radiometric value be the same?
the real example is : On 2 same images (same scene and same sunlight), if there is a different exposure camera setting (iso, shutter, aperture), will the radiometric value be the same? (if there is no DLS).

The point of the question is to better understand the best workflow I should use.
Should I use camera exposure setting in AUTO or should I keep the exact same camera exposure setting and stay in MANUAL:
- in case I use camera with DLS ?
- in case I use camera without DLS ?

Thanks :-)