View Full Version : Soft focus work around?

25-Feb-2004, 16:35
Can I take a lens cap, drill a large hole in the middle and two rows of smaller holes around the outside edge, (sink strainer looking) and achieve a poor mans soft focus lens? Just wondering (before I ruin a lens cap.) dee

David A. Goldfarb
25-Feb-2004, 16:46
Not really, but try it just to see what will happen using a piece of cardboard attached to the lens, so you don't have to ruin a lens cap.

25-Feb-2004, 17:44
Your question suggests you take your inspiration from the discs associated with the Imagon soft-focus lens. The discs do control the amount of softness. But unless I'm mistaken, it's not the discs, but the lens itself which creates the softness. The discs merely control the amount.

Spherical aberration is usually what's used to gain softness and that particular aberration is more pronounced in off-axis rays. The central portion of the lens (along the optical axis) contributes little to the softness. But light which passes through the area of the lens closer to the edge (off-axis) is subject to more and more spherical aberration the further off-axis it is. This is why many soft-focus lenses are sharp when stopped down, but quite soft at wide apertures. The discs with the pattern you describe provide a central stop which accounts for the basic image. The peripheral holes allow some of the off-axis rays to add softness to the image. Such a disc added to a well-corrected lens should simply provide less illumination overall without degrading (softening) the image. If you can introduce some spherical aberration into your lens, perhaps by adjusting the spacing of the elements, then you might achieve the result you're looking for.

Ken Lee
25-Feb-2004, 17:45
Couldn't you introduce this effect in the darkroom, by printing through some kind of screen or mesh ?

david clark
25-Feb-2004, 18:02
Hi D.S. as a matter of fact, if you did it correctly, I think would improve the resolution of the image the same way you would if using a larger f-stop. Best, David

David A. Goldfarb
25-Feb-2004, 18:07
This effect is not the same as diffusion in the darkroom. A soft lens or even diffusion on a sharp taking lens will cause light from the highlights to spill over into the shadows. Diffusion in the darkroom has the opposite effect.

Diffusion in the darkroom can be done subtly--I've seen good results from someone who used a Softar under the enlarging lens for 1/3 the printing time--but go too far and you'll get more of an Addams Family effect. Mapplethorpe did this occasionally to make certain subjects look a little sinister (or at least that's the effect it had).

Steve Hamley
25-Feb-2004, 19:30

Let's back up. I have a 300 mm Imagon. I'm under the impression that the maximum diffusion is obtained with no discs - the rear element and nothing else. The discs sharpen the image. So no, for a normal type lens, because the "default" setting is no diffusion, not maximum diffusion.

But the beauty of LF is try it and see!


Darin Cozine
25-Feb-2004, 21:47
Arent the sink strainer apertures supposed to help the bokeh of a lens?

Cesar Barreto
26-Feb-2004, 04:38
No, bokeh has nothing to do with sink strainer apertures, wich are useful to control spherical aberration on specific lenses planned to offer soft images of well focused subjects. Bokeh deals with subjetive qualities of out-of-focus image planes. So they're almost opposite! Merklinger suggests a poor man soft focus solution: focus a little bit closer than infinity mark. That's difficult with fixed cameras and so easy for lf ones. Once done, everything comes equally out-of-focus through the whole image, obviously, still under control of aperture and how much far from infinity one gets.

Paul Schilliger
26-Feb-2004, 13:53
Dee, There are some lenses that produce a soft focus effect when one of the lens element is removed. I had noticed this with a modern Super-Angulon. It's a matter of introducing some optical aberration as it was well explained above. Another way to achieve the wanted effect is by using a soft focus filter such as ProSoft, HiSoft or Softar clones. There is also the Photoshop effect by superposing a blurred layer to a normal layer and adjusting the transparency. Some more refined ways also by blurring the highlights. It's a nice field for experimentation!

Dominique Cesari
27-Feb-2004, 12:32
Spare your lens cap, don't drill it, you will get nothing that way, for the reasons that William gave. If you want a (very) poor man's soft focus effect, you may try borrowing pantyhose from your (wife), (mate), (female relation), (local drag-queen)... and cover the front of the lens. Be oecumenic, as try and successes are surely necessary to reach the level suited.

(by the way, I have an Imagon, for sure the maximum diffusion is reached with no disks on, but the result is way too soft)

28-Feb-2004, 08:16
Thanks, I'll play around with removing lens fronts, selective focus, and I'm curious as to what happens if I take the front end off one lens and put it on the front of another. (within the same shutter size.)


Armin Seeholzer
29-Feb-2004, 03:15

There is an other very nice possibility I learned it from a german guy wich had an article in Color Foto german Mag. But till now I only tested it as recommended with zoom lenses on 35 mm format. But does not work with flashs only with the controlling lights of the flash or with other normal lighting! You take a time for 1-3 sec. and during the first second just do nothing but the rest of the time you start zooming out. You can do thies with different times but as longer as you stand still as a lesser effect you get! Just check if it can also be done with LF if you go a bit out of focus during exposing. Just be creativ and forgott all rules is sometimes a must and you find out a new effect! But for a controlled effect I really like my Imagon!