Imagon Softness Range

I've already posted this to the Medium Format forum because I'm using a 200mm Imagon on my Hasselblad, but it's possible that my question would be best answered by Large Format users. Can someone please explain which aperture settings would provide maximum sharpness and maximum softness? Can someone suggest which settings would pprovide softness without going to extremes?

You do not use an aperture ring with an Imaging. You either shoot for maximum softness with no disk in front of the lens or with one. Of the 3 Imaginq disks.each disk has a different size center hole. With the disk with the largest center hole and with all periphery holes open you are at 5.8 which is the same exposure as no disk and you are at maximum softness with a disk. With the periphery holes closed you are at 7.7. With the disk with the middles sized hole and all periphery holes open you are at 7.7 and will be slightly sharper. This is the disk and setting that most classic portrait photographers used. This includes Zucker, Horvath, Gilbert, . That disk with the periphery holes closed will be sharper again. The last disk with the periphery holes open will be the same exposure as the middle disk with holes closed but will be sharper again. With all holes closed on this last disk the lens is very sharp.

It is important to note that the Imaging needs a very strong lighting ratio of 5:1 and should not be used with flat light sources like an umbrella. It require strong spectral highlights for the Imaging look. That means an elliptical type reflector for a main light.

Mastering the Imagon requires a lot of practice. Also, the Imagon changes focus with each change of disks or disk setting so you must focus at your desired setting. Since there is no point of critical sharpness with an Imagon you also have to learn through practice what a properly focused image looks like on your focusing screen.

Edited August 21, 2017 by bob_salomon

Very helpful, Bob. Thanks.