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Bill_1856
23-Dec-2014, 16:25
For example, can you focus the ground glass on one point, say the near eye, and then adjust the aperture to get the soft-focus effect that you prefer? Or do you have to readjust the focus every time you shift aperture?

jp
23-Dec-2014, 18:30
I've never stopped down more than a stop on my veritos! It's still plenty bright to focus at 5.6 so I do if I'm using that aperture. Saves a step or potential error when shooting having to remember to adjust the aperture.

Mark Sawyer
23-Dec-2014, 18:32
Yes, the Verito has a focus shift when you close the aperture. All lenses with spherical aberration have focus shift, because as you shut them down, you're selectively shutting off the image-making light from the outer edges which is focusing in a different place. As those go away, the plane of dominant focus shifts.

Bill_1856
23-Dec-2014, 20:00
Yes, the Verito has a focus shift when you close the aperture. All lenses with spherical aberration have focus shift, because as you shut them down, you're selectively shutting off the image-making light from the outer edges which is focusing in a different place. As those go away, the plane of dominant focus shifts.
Thanks, Mark.
Is that a theoretical answer, or do you have practical experience with the Verito?

Randy Moe
23-Dec-2014, 20:22
Yes, the Verito has a focus shift when you close the aperture. All lenses with spherical aberration have focus shift, because as you shut them down, you're selectively shutting off the image-making light from the outer edges which is focusing in a different place. As those go away, the plane of dominant focus shifts.

That Verito brochure you just posted elsewhere with the diffusers, said to focus sharply at f32 and then insert the SF WHS. This is the same type of original info that confused me with my Cooke Series II, where they change their minds about how to use SF over a few decades with the same lens.

Also focusing sharply at f32 is a difficult feat.

However they began that treatise by writing, 'Controllable diffusion in enlarging...'

SF has got me on the run...

Mark Sawyer
24-Dec-2014, 01:17
There's always been confusion about focusing a soft lens. Wollensak had conflicting advice about focusing the Velostigmat Series II with diffusion too. But in every case, when you close the aperture, you change the nature of the spherical aberration. The light from the outside of the lens is focusing closer than the light from the center of the lens.

And yes, I've used the Verito's a fair amount.

From my 18 inch Verito...

goamules
24-Dec-2014, 05:36
I would call Mark "The Verito King". He knows what he's talking about.

Randy Moe
24-Dec-2014, 06:59
There's always been confusion about focusing a soft lens. Wollensak had conflicting advice about focusing the Velostigmat Series II with diffusion too. But in every case, when you close the aperture, you change the nature of the spherical aberration. The light from the outside of the lens is focusing closer than the light from the center of the lens.

And yes, I've used the Verito's a fair amount.

From my 18 inch Verito...

Looks not real, but the water spray solves that. Interesting miniature effect. Thanks for sharing!

David A. Goldfarb
24-Dec-2014, 10:08
I find it useful to focus at f:8, and then open up while looking at the groundglass until the desired effect is achieved, kind of like layering the diffuse image on the sharp image, then I might tweak the focus a bit, but often not. I almost always end up around f:6.

Bill_1856
24-Dec-2014, 12:47
Mark, how much is the focus shift -- a lot or a little? Is it easy to do, or a PITA?
I am contemplating buying a 9" Verito from Japan for my 5x7, and don't want any big surprises.
I am using a Dr. Stable Poly-Plast casket set for my 4x5, with a fixed rear set and four interchangeable front elements giving 105, 135, 165, and 195mm focal lengths, and 230mm for the rear element alone. Fortunately, I can focus wide open and then when stopping down to f:16-22 it is only necessary to roll the front standard forward 1/4" for perfect focus. (If the rear element is used alone, I have to back it up 1/4"). A real pleasure to use in its tiny little totally-silent Compound shutter.
I appreciate your interest and advise.
Bill

goamules
24-Dec-2014, 12:56
I find Veritos easy to focus. I usually do as David says, stop down a little to focus to about F8, then open it up to the level of softness I want. I may rack the focus in and out a few millimeters to check at that point, but never find I need to change much. It's kind of hard to focus them at F4.5 though.

Randy Moe
24-Dec-2014, 13:07
All this is good advice!

Mark Sawyer
24-Dec-2014, 13:10
Mark, how much is the focus shift -- a lot or a little? Is it easy to do, or a PITA?
I am contemplating buying a 9" Verito from Japan for my 5x7, and don't want any big surprises.
I am using a Dr. Stable Poly-Plast casket set for my 4x5, with a fixed rear set and four interchangeable front elements giving 105, 135, 165, and 195mm focal lengths, and 230mm for the rear element alone. Fortunately, I can focus wide open and then when stopping down to f:16-22 it is only necessary to roll the front standard forward 1/4" for perfect focus. (If the rear element is used alone, I have to back it up 1/4"). A real pleasure to use in its tiny little totally-silent Compound shutter.
I appreciate your interest and advise.
Bill

It's not a PITA; the amount of shift is surprisingly small considering the amount of spherical aberration the Verito has wide open. I'd call it fine tuning, maybe 1/16th or 1/8th of an inch or so at most. My method is to focus, then close down, then re-focus carefully with a loupe, (although I'm also too-often guilty of using Verito's wide open, which is pretty heavy-handed). The method David and Garrett use works just as well for them. It's pretty simple, and what you see on the ground glass is what you'll get on modern panchromatic films.

The Verito is one of the easiest to use true soft focus lenses, and I think one of the most beautiful in the results it can give. And don't forget the 9-inch Verito converts to a 14-inch too!

mdarnton
24-Dec-2014, 14:18
I noticed on one of my cobbled up lenses that when I focus it seems that an object suddenly becomes sharp, stays sharp for a while, then suddenly goes unsharp, so what I do is focus forward to find the closest I can focus to keep that sharpness, and that's where I stay. Effectively, I guess it's placing the focus forward which then can move backwards if it wants, since that's the way it will move if it does.

This is an undeveloped new idea, so I'm certainly open to comments. That thing of staying pretty sharp through a long range was new and interesting to me, once I noticed it, which did take a while.

Mark Sawyer
24-Dec-2014, 14:43
I noticed on one of my cobbled up lenses that when I focus it seems that an object suddenly becomes sharp, stays sharp for a while, then suddenly goes unsharp...

That's the focus being spread by spherical aberration. When Dallmeyer introduced the first soft focus lens, (the Patent Portrait lens in 1866), soft focus wasn't about the soft look, it was about spreading the depth of field. The range of sharpness as you focus is the range different parts of the lens (outer edge vs. center) are focusing sharply at.