Hello - I'm not sure where you source your information here.
I gave links to the sources in my earlier reply. 1) The
Hasselblad FlexBody manual. 2)
User supplied shift data from a thread on the topic a decade ago on Luminous Landscape. The latter includes the 180 mm lens which has been discussed.
An additional technical note, 6x6 cm is the
nominal Hasselblad image size. The actual image size is approximately 55 x 55 mm (as given in the FlexBody manual chart of lens shift range). The image diagonal is approximately 78 mm.
In addition to being able to use the full square format, the FlexBody (and some later model V cameras) can be used with a variety of masks inserted in the
back of the camera body (or simply cropped after capture) for various rectangular aspect ratios. Among them is a set (
Cat #41151) which includes a "6x4.5" (approximately 42 x 55 mm) format mask which reduces the image diagonal to approximately 69 mm and a "6x3" ratio panoramic mask. Included with the FlexBody is a "4x5" mask (40 mm x 50 mm) which has an image diagonal of 64 mm. When using 6 x 4.5 or 4 x 5 as the aspect ratio, the usable shift range with the FlexBody increases for the 80 mm and shorter focal lengths as well as the 250 mm.
THE Ernst Wildi himself made this 6x6 image circle claim in his Hasselblad Manual 'Bibles, of which I had several editions up to the Fourth.
Yes. I'm well acquainted with "THE Ernst Wildi himself". If you'd prefer getting information for V series lenses and their maximum recommended shift with the FlexBody from him, it can be found on
page 224 (Table 13-1) of his 7th edition of The Hasselblad Manual. His recommendations are the same as in the FlexBody manual which I linked earlier, but with the useful addition of maximum shift recommendations for the included 4x5 format mask. * There is a minor error in the Wildi Hasselblad manual which states that the 6x4.5 mask is included with the FlexBody—it is the 4x5 mask which is included.
Full square format: 40 mm - 0; 50 mm - 5 mm; 60 & 80 mm - 10 mm; 100 & 120mm - 14 mm; 250 mm - 10 mm
With Mask: 40 mm - 7mm; 50 mm - 12 mm; 60 mm thru 250 mm - 14 mm * The maximum shift range of the FlexBody is +/- 14 mm.
The rear tilt mechanism does not move the image plane outside of the lens image circle and is very useful in situations where the lens on the camera base rail axis and back are both tilted for the desired perspective and depth of field control
as in this example. Also, I'll note here again, when focusing closer than infinity, your image circle will generally increase in approximate proportion to magnification although this depends on the lens design.
The precise wording he uses in discussing
generally the "limited covering power" of the V series lenses is with regard to the maximum format the "lenses were
designed to cover". That's correct. The lenses were
designed to cover the maximum film format of the various V system cameras (nominally 6 x 6 cm). However, the image diagonal the lenses are
designed to cover and the image diagonal that they are
actually able to cover is not the same thing. There are users of tilt-shift lenses
designed for 35 mm (24 x 36 mm) format now using those same lenses with current 33 x 44 mm medium format cameras successfully.
As is generally the case with any lens, as you move away from the center of the image circle toward the edges resolution and contrast decrease and vignetting increases. Some FlexBody users feel that the Hasselblad recommendations are a little conservative and find results acceptable for their needs a bit beyond the suggested limits. This is determined by the individual user's requirements and the specific lens being used.
