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© Rodenstock GmbH
Status: September 2023
focus, a change in the customer's position - a small
step forward or backward - can help.
Why is the image slanted and does not show the
customer head-on?
This is due to the positioning of the cameras in the
carriage. This in turn is essential for the patented
stereo measurement principle.
Does the ImpressionIST® 4+ need to be calibrated
regularly?
Does the ImpressionIST® 4+ have to be recalibrated
after a change of location?
In principle, the ImpressionIST® 4+ can be checked
and, if necessary, recalibrated by a trained employee
of the Rodenstock Customer Service System. This
must be taken into account when changing the
location.
When exactly is the photo saved? Immediately after
triggering, or after the first crosses are set?
The image is saved immediately after the shutter is
released.
Where exactly should/must the horizontal bar of the
frame be placed? On the frame, or on the edge of the
glass?
Align the horizontal line of the frame at the transition
between the front surface of the lens and the edge of
the frame. Refer to the uppermost points of the
transition. These points correspond to the maximum
upper box dimension.
In a cross-eyed/alternating person, is it worth taking
an image to adopt all parameters except PD/height
(Can CVD also be adopted in these cases)?
The CVD and the face form angle can be adopted
with certainty.
Why center on the pupil center and not on the
pupillary reflex?
The pupillary reflex represents the apex of the
cornea. However, this does not necessarily have to
coincide with the geometric pupil center, but is off-
centered in most cases. The decisive parameter for
data processing is the geometric pupil center.
Will the new software (CNXT®) of the
ImpressionIST® 4+ also be available for the
ImpressionIST® 3 and ImpressionIST® Avantgarde?
Even though all CNXT® versions will be updated
automatically, the ImpressionIST® module will only
be available for ImpressionIST® 4, not for older
predecessors of the ImpressionIST® 4+.
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