Pitfalls
● Poor Focus – This is the most basic factor to
adjust correctly. Focused parts should ideally
include all important parts of the image.
● Wrong f-stop causing poor Depth of Field –
Shooting at low f-stop as often happens with
automatic camera settings can cause a
major part of your object to be out of focus.
For the best focus, a stop down between f/8
and f/16 is recommended; above these fstop
values, diffraction sets in and reduces
the overall sharpness, rather than increasing
it. Check on internet resources (i.e.,
www.DPReview.com) to find the best f-stop
for certain lenses.
● Too few images usually result in bad
alignment, and thus gaps and errors in the
model.
● Too little overlap (as above).
● Too many images increase calculation time
for no gain. Worse, too many images can
lead to artifacts by grouped alignment
creating two points where there should be
only one. However, it is advisable to take
many photos and use only a selection for
photogrammetry, especially if the specimen
is not at one’s disposal.
Pitfalls
● Poor Focus – This is the most basic factor to
adjust correctly. Focused parts should ideally
include all important parts of the image.
● Wrong f-stop causing poor Depth of Field –
Shooting at low f-stop as often happens with
automatic camera settings can cause a
major part of your object to be out of focus.
For the best focus, a stop down between f/8
and f/16 is recommended; above these fstop
values, diffraction sets in and reduces
the overall sharpness, rather than increasing
it. Check on internet resources (i.e.,
www.DPReview.com) to find the best f-stop
for certain lenses.
● Too few images usually result in bad
alignment, and thus gaps and errors in the
model.
● Too little overlap (as above).
● Too many images increase calculation time
for no gain. Worse, too many images can
lead to artifacts by grouped alignment
creating two points where there should be
only one. However, it is advisable to take
many photos and use only a selection for
photogrammetry, especially if the specimen
is not at one’s disposal.
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