I can't tell you how many soft focus lenses have passed through my hands. It started with my participation in the early days of eBay. Some of the optics I have owned, put on the shelf, and then sold unused by me were brilliant. A Pinkham Smith. A Verito. Something very rare that got shipped to Japan. It nearly breaks my heart thinking of it all.
I convinced myself each and every time that I prefer very sharp contrasty images to the classic soft focus Mortenson kind of image. I say "convinced" since I never ever actually tried my hand at any of it.
Recently, I have come close to dumping all my LF gear and going straight MF and digital. Scanning MF negs yields 50mbyte sized files with enough detail to make a LF guy weep.
As the wheel of life turned, a very inexpensive 150mm Mamiya RB f/4 Soft Focus lens came my way. It arrived last week. I swore an oath that I would not let this lens go until I had a chance to try it.
So... this past weekend I hauled the Mamiya RZ up out of the basement, mounted it on a tripod, grabbed my wife's very beautiful bouquet of roses that she grew and cut just before the rain hit, and put them somewhere I could focus on them. The light coming into the living room where we were working on these images is north light. It is the most fabulous light to work with.
The film was Kodak TMax100 rated at ISO 50, souped in Rodinal 150:1 for 20 mins at 72F with agitation 5seconds every minute. The negs were then scanned using a Nikon 8000ED film scanner. The processing was through the Gimp (no Photoshop here!) with minimal curve manipulation (I pulled the bottom end of the curve snug against the lowest value on the image). I then took a gum over palladium tint and sample colorized it over the base image.
150mm Mamiya RB f/4 Soft Focus lens at f/4 - This image used no diffusion disks and is shot wide open. It is understandably very soft. There is a nice glow about the highlights that bleed into the shadows.
150mm Mamiya RB f/4 Soft Focus lens at f/5 - This image used f/5 diffusion disk. It is understandably still very soft. The glow around the highlights that bleeds into the shadows is less than the an image shot without a disk.
150mm Mamiya RB f/4 Soft Focus lens at f/5.6 - This image used the f/5.6 diffusion disk. The image softness is better controlled than when shot with either the f/5 disk or no disk wide open at f/4. The image appears to glow and gives what appears to me to be a very pleasing effect.
150mm Mamiya RB f/4 Soft Focus lens at f/6 - This image used the f/6 diffusion disk. This disk has a smaller center hole, as one would expect from a smaller aperture, and the tiny holes that surround the center hole that allow the spherical aberrations through to reach the images from the edges of the optic are quite numerous. I am amazed at how much softer this f/6 image appears than the f/5.6 (with it's wider center hole and fewer tiny surrounding spherical aberration passing holes. Still, the effect is quite pleasing.
150mm Mamiya RB f/4 Soft Focus lens at f/8 - This image used no diffusion disks and on the in-lens aperture set at f/8. There is some glow in the highlights that come from the design of the optics. But at this point, the effect is minimized. It appears that by f/11, the Mamiya 150mm behaves just like any "properly corrected" photographic lens.