Fujinon Soft Focus Lens

This is probably a dumb question, but the 250mm soft focus lens: It's a
regular lens that one can use like any other LF lens; additionally,
there are two disks (=filters?) that one can optionally use for
increasing soft focusing?

Thanks.
RON

Ron Gans wrote:
This is probably a dumb question, but the 250mm soft focus lens: It's a
regular lens that one can use like any other LF lens; additionally,
there are two disks (=filters?) that one can optionally use for
increasing soft focusing?

Thanks.
RON


I believe that the lens has lots of spherical aberation. The disks have
various holes in them that allow more or less light from the edge of the
lens to form an image. I expect that used without the disks that the
lens would be very soft. Hopefully someone who actually has one can
confirm or deny this.

-Peter
www.desmidt.net

Ron Gans wrote:
This is probably a dumb question, but the 250mm soft focus lens: It's a
regular lens that one can use like any other LF lens; additionally,
there are two disks (=filters?) that one can optionally use for
increasing soft focusing?

Thanks.
RON


I believe that the lens has lots of spherical aberation. The disks have
various holes in them that allow more or less light from the edge of the
lens to form an image. I expect that used without the disks that the
lens would be very soft. Hopefully someone who actually has one can
confirm or deny this.

-Peter
www.desmidt.net

"Ron Gans" wrote in message
ps.com...
This is probably a dumb question, but the 250mm soft focus
lens: It's a
regular lens that one can use like any other LF lens;
additionally,
there are two disks (=filters?) that one can optionally
use for
increasing soft focusing?

Thanks.
RON
The Fuji lens appears to be similar to the well known
Rodenstock Imagon. This lens makes use uncorrected
spherical aberration as do many other soft focus lenses
but appears to control it in a different way. Spherical
abberation is due to the fact that spherical surfaces can
not focus light coming in near the center of the lens
simutaneously with light coming in toward the edges. In
effect the focal length varies from center to edge so the
image is an overlay of many images. The effect is both an
over haze and a sort of halo effect around bright
highlights. Spherical varies with the stop. The more the
lens is stopped down the sharper it gets. You can
demonstrate this with a desk magnifying glass by making
stops of black paper.
The Imagon lens is able to balance the light from center
to edge and control exposure to some degree independantly
but using disc with both a central stop and holes around the
periphery. The peripheral holes let a controlled amount of
light in at the edges and the central hole at the center. By
adjusting the relative amount of light the softness can be
adjusted. In addition the peripheral holes also provide some
diffusion since each is a sort of large pin hole. This
changes the nature of the softness to one which can not be
duplicated with a simple soft focus lens. AFAIK, the Fuji
lens operates on exactly the same principle as the Imagon
although it is not indentical to it.


--
---
Richard Knoppow
Los Angeles, CA, USA

I hate to ask the obvious: but without the disks, is this a "regular"
lens? I.e., one that I can use for tack sharp images at all aperatures
(with the usual DOF restrictions)? That is to say, is it in some way
altered to assume the use of these disks?

Ron Gans wrote:
I hate to ask the obvious: but without the disks, is this a "regular"
lens? I.e., one that I can use for tack sharp images at all aperatures
(with the usual DOF restrictions)? That is to say, is it in some way
altered to assume the use of these disks?


No, I don't think it's a regular lens, and therefore no you can't use it
for tack sharp images at all apertures. Yes, this lens has more
aberations than other lenses. However, that's just my understanding. If
I were you, I'd email someone who carries the lens, say Jeff Taugner at
Badger Graphic Sales, and ask him. www.badgergraphic.com

-Peter De Smidt

On 2005-02-21 09:44:23 -0500, Peter De Smidt
pdesmidt*no*spam*@tds.*net* said:

Ron Gans wrote:
This is probably a dumb question, but the 250mm soft focus lens: It's a
regular lens that one can use like any other LF lens; additionally,
there are two disks (=filters?) that one can optionally use for
increasing soft focusing?
Thanks.
RON


I believe that the lens has lots of spherical aberation. The disks have
various holes in them that allow more or less light from the edge of
the lens to form an image. I expect that used without the disks that
the lens would be very soft. Hopefully someone who actually has one can
confirm or deny this.

-Peter
www.desmidt.net

Looks are deceiving. Peter's answer is correct for the Imagon which
the Fujinon softfocus lens ;ooks like but the Fuji works differently.
The Imagon is at is softest with the most aberation when used without
the halation discs. The Imagon has a single behind the shutter cell.
The Fuji, OTOH, has the more normal two cells,, one behind an done in
front of the shutter. The Fuji used without a disk is a sharp lens and
performs normally. The insertion of a disk beetween the front of the
shutter and the front element difuse the light and give softness.

Only the looks are the same as the looks of the Imagon. The performance
is quite different. The lens softens but the 'halation' (read star
shaped highlight) and luminous effect is rather different than that
acheived with the Imagon. I used one of these lenses briefly a few
years ago and was not satisfied with its performance.

So, basically you are saying that if I wanted the Fujinon 250 for
non-soft focus work, it should perform as well as any other (pretty
much) 250mm lens, like a Schneider or Rodenstock (well, the 240mms).
And, if I do portrait work (which I normally don't) I could opt for the
soft focus disks.

"Ron Gans" wrote in message
oups.com...
So, basically you are saying that if I wanted the Fujinon 250 for
non-soft focus work, it should perform as well as any other (pretty
much) 250mm lens, like a Schneider or Rodenstock (well, the 240mms).
And, if I do portrait work (which I normally don't) I could opt for the
soft focus disks.


I don't own the fujinon, but from descriptions here it sounds a lot like the
Mamiya 150mm soft focus lens for the RB67, which also has disks and is also
supposed to be sharp as a regular lens from f8 on up. However, even without
the disks in and stopped down, it still maintains some of the soft focus
effects, so much so that I'm contemplating the 180 to fill the niche. It
just isn't "normal" enough for my tastes.

--
Regards,
Matt Clara
www.mattclara.com

"Ron Gans" wrote in message
ups.com...
I hate to ask the obvious: but without the disks, is this a
"regular"
lens? I.e., one that I can use for tack sharp images at
all aperatures
(with the usual DOF restrictions)? That is to say, is it
in some way
altered to assume the use of these disks?

No, the softness comes from delibrately uncorrected
spherical aberration. Since this is contributed by the outer
portions of the lens the diaphragms control how much is in
the image. The diaphragms also control the amount of light
going through the lens, at least in the Rodenstock Imagon
version. If the Fuji version has a separate iris diaphragm
it will also control the amount of softness, the lens
becoming sharper as it is stopped down. Soft focus lenses
can become sensibly sharp at small stops but are never quite
as sharp as a corrected lens. This is not a good choice for
a general purpose lens.


--
---
Richard Knoppow
Los Angeles, CA, USA