The Rodenstock HR Digaron-SW float 138 mm f/6.5 is an exceptional sharp long focal length lens for
adjustable technical cameras intended for a wide distance range from infinity up to an
image scale 1:5 (β' = -0,2).
The optical design with eleven lens elements in ten groups is very complex for a prime lens.
It has the highest possible resolving power extremely close to the diffraction limit.
This is not only achieved across the entire field of the largest digital sensors – but also to the edge of the
large 110mm image circle to allow for lens shifts and tilts.
The rotation of the focusing ring automatically controls the floating elements group and all
aberrations are therefore minimized throughout the whole focusing range.
Even with extreme camera movements (shift and tilt) this lens provides an unprecedented
sharpness to the corners as proven by the MTF curves given up to 80 lp/mm .
It provides negligible distortion (almost always below 1‰) and a total suppression of the
chromatic aberration for perfect freedom from color fringing.
The image circle of the HR Digaron-SW float 138 mm f/6.5 has a constant diameter of 110 mm throughout its entire image scale range. For professional technical cameras, even with the largest
sensor formats, this gives ample clearance for parallel shifts for perspective corrections
(avoiding or reducing converging vertical lines). This also allows swing and tilt for extended
depth of field without excessive stopping down of the aperture according to the Scheimpflug rule.
The broad focusing ring of the helical mount allows sensitive and precise focusing and automatically controls the adjustment of the floating elements group mentioned above.
|
Shortest focal distance to object: approx. 1.0 mtr
Image circle of lens at any f/stop: 110 mm
Optical Movements:
CCD size 37x37mm: 33/33 mm
CCD size 33x44mm: 34/30 mm
CCD size 36x48mm: 30/26 mm
CCD size 37x49mm: 31/27 mm
CCD size 40x54mm: 28/24 mm
CCD size 36x56mm: 29/24 mm
Please note that some optical movements may be larger than achievable due to mechanical limitation.
|