Accessories - Hasselblad 503CW User Manual

In the diagrams, all exit pupils are viewed from
the image corners.
Diagram A
Exit pupil for a wide-
open lens
A
Diagram B
Exit pupil for a
vignette-free stopped
down lens
B
Diagram C
Exit pupil for a slightly
vignetted lens (no
visible effect on the
image)
C
Diagram D
Exit pupil for a vignet-
ted lens (clearly visible
effect on the image)
D
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Accessories

Most of the accessories supplied are either self-explanatory or covered in other sections of this man-
ual. The Rear cover Multicontrol requires a more in-depth explanation.
Rear cover MultiControl (supplied)
The Rear Cover MultiControl (3051070) not only provides protection for the camera body
when a digital capture unit or film magazine is not attached but also provides flash check
facility for cameras featuring TTL/OTF (described separately) as well as a vignetting check
facility.
Checking for possible vignetting is useful when filter combinations, attachments or lens
shades are used, to ensure the optimum from the accessories without the risk of inadver-
tant vignetting.
With the cover in position you can see the so-called 'exit pupil' of the lens through the
small holes in the cover. A vignetting free lens has an exit pupil the exact shape of the lens
aperture. At maximum aperture there is slight vignetting with all lenses but at f/11 to f/16
the majority of lenses are free of vignetting.
Corner illumination is dependent on the size of the exit pupil. If the filter or lens shade
extends too far, the area of the exit pupil diminishes. The shading effect of a professional
lens shade, for example, is optimal when it has been extended as far as possible without
causing any visible corner vignetting. The amount of this extension is dependent on both
the working aperture and the focusing distance for the lens used.
Use the following method when any kind of lens accessory is in place and you want to
ensure a result free from vignetting:
1. Fit the accessory. Remove the film magazine but do not attach a Rear Cover
MultiControl just yet.
2. Set the shutter on a CF/CFi/CFE lens at the 'F' position and pre-release the camera to
open both the lens shutter and the auxiliary shutter. C/CB lens shutters should be set
at 'B' and a B exposure made. Use a cable release to lock the released position.
3. Look at the lens exit pupil. Use the stop-down button and change the aperture
noticing as you do so the changes in the size of the exit pupil.
4. Look now at an angle roughly in a line from the exit pupil to one corner of the
camera back opening. This helps in finding the exit pupil again when the RCMC is
attached, which can be troublesome with wide-angle lenses in particular.
5. Attach the RCMC and observe the exit pupil again.
6. Select the working aperture and stop down manually.
7. Set the approximate focusing distance.
8. See the diagrams for a fuller explanation of what you can now see through one of
the holes, and act accordingly.
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