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With the used enlargement, the principal point of the images with a size of 24 mm
* 36 mm is located 50 mm outside the centre of the photos. The corresponding
base to height ratio 100 : 380 = 1 : 3.8 enables a sufficiant stereoscopic
impression.
The lens distortion is reaching 150 pm. It is mainly radial symmetric, but not in
relation to the principal point. The point of symmetry is located 6 mm beside the
photo centre. The inner orientation and also the lens distortion cannot be
reproduced, it will be influenced by any change of the focus and enlargement. In
addition the photo resolution has been poor. By theese reasons a switch was made
to the partial-metric camera Rolleiflex metric 6006 and 3003 with macro converter
and macro lenses.
4. Rolleiflex metric with macro lenses
The Rolleiflex metric includes a reseau infront of the film. The 6006 has a photo
size of 60 mm * 60 mm, the 3003 24 mm * 36 mm. The extended image size of
the 6006 includes the advantage of a better angular resolution.
Rolleiflex metric 6006 | Rolleiflex metric 3003
2-fold converter
yes
yes
yes
yes
no
adapter ring
34 mm
68 mm
102 mm
2 *
3 *
focal length
218 mm
275 mm
337 mm
258 mm
138 mm
photo scale
1 : 1.2
1.7 : 1
2.5 : 1
2.6 : 1
1.5 : 1
mean distortion
31 pm
13 pm
14 pm
18 pm
10 pm
table 1: used Rolleiflex configurations
Because of the small view angle no reseau correction for compensation of the film
flattening was necessary. The inner orientation has been determined with the same
three-dimensional control pattern described before.
With long focal length in the normal case only a poor base to hight relation can be
reached. So a tilted view to the object is necessary. The handled samples have
been small but the cameras have had a very long combination of adapter rings,
converters and lenses, by this reason the object was located on a tilting table and
the camera has been fixed.
fig. 4
configuration for
Rolleiflex metric
