The lens type Rodagon, with focal lengths up to 135mm have proven to be excellent high-resolution taking lenses for CCD cameras in combination with the Rodenstock focusing device Modular-Focus.

Modular Focus

Rodagon lenses do not have a helical focusing facility. If these lenses are used as taking lenses, it is necessary to fit a focusing device. The Modular-Focus developed for this purpose has a stroke of 25 mm and offers high setting precision and stability. The straight-line guide guarantees that the lens does not rotate with the focusing ring.

LENS	MAX SENSOR SIZE (mm)	F, T, AND SLR-MOUNT MAG RANGE	C AND M72-MOUNT MAG RANGE
28 f/2.8	25	NA	0.58 – 1.49
35 f/4.0	30	NA	0.24 – 1.67
50 f/2.8	40	0.62 – 1.12	0 – 1.49
60 f/4.0	50	0.27 – 1.14	0 – 1.39
80 f/4.0	62	0 – 0.96	0 – 0.86
105 f/5.6	70	0 – 0.71	0 – 0.40
135 f/5.6	80	0 – 0.35	0 – 0.12

It takes a lens adapter, focus block, and camera adapter to couple a lens to a camera. The minimum path length of the above three items (LA) is 19.6mm for c-mount, and 21.6mm for f-mount. This distance may be increased by 25mm using the focus block expansion. Additional 25mm spacers may be required.


Rodenstock M72 x 0.75t Focus System



To accommodate the new larger format cameras with the larger non-standard mounting threads, an M72t mounting system is available.

An additional M72t camera adapter is available along with M72 Extension Tubes.

Note the revised position of the Extension Tubes to clear the larger image beams.

For those cameras with a thread smaller than M72, a "step-up" ring must be used. These may be found at www.photofilter.com

The first number of the ring will be your camera thread, the second will be M72.

The wizard assumes a flange distance of 6.56mm, for an M72 mounting thread. If you procure a step-up ring for an M58 mounting thread, and the flange distance is 30mm, as an example, it will be necessary to remove one of the 25mm Extension Tubes to accommodate.