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General / Re: Sony A7rii for photogrammetry and lenses
« on: January 24, 2020, 01:08:44 AM »
FYI. The Sony A7rii camera uses 5-axis image sensor stabilization. This means your sensor is moving which is a bad thing for photogrammetry. You'll have alignment errors within your data. You should at least turn that option off if you use that camera, but its hard to say how rigid that mechanism really is.
One of the rules of photogrammetry is consistent photos between your images, to maintain good geometry for the reconstruction (alignment step). Don't go with a zoom lens, stick to prime lens to eliminate the focal length movement between your photos. Plus they are sharper, which helps support pixel matching producing accurate tie points to sub pixel levels. Also, a wide angle lens will typically have a better base to height ratios, helping the software calculate your distance to that surface more accurately.
One of the rules of photogrammetry is consistent photos between your images, to maintain good geometry for the reconstruction (alignment step). Don't go with a zoom lens, stick to prime lens to eliminate the focal length movement between your photos. Plus they are sharper, which helps support pixel matching producing accurate tie points to sub pixel levels. Also, a wide angle lens will typically have a better base to height ratios, helping the software calculate your distance to that surface more accurately.
