Re: dreamy Nikon lenses

[Richard Knoppow <dickburk@ix.netcom.com>]

----- Original Message ----- 
From: "Jack Brubaker" <jack@jackbrubaker.com>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, July 21, 2008 10:48 AM
Subject: Re: dreamy Nikon lenses


> To the lens experts out there...
>
> I have a question about using an old lens as soft focus. 
> Someone
> mentioned that an old triplet could be made to give that 
> soft halo
> effect by moving the front element out a bit to introduce 
> spherical
> aberration. Do I remember that right? If so can this be 
> done with some
> of those old lenses I have laying around that have what I 
> take to be a
> front pair and a rear pair each mounted in a brass ring 
> and threaded
> into a brass tube. Can the space between the front and 
> rear elements
> be varied by screwing them out a bit and get any of these 
> effects, or
> by seperating the front pair and placing a shim between 
> them in the
> brass mounting ring?
>
> Hopeful and expectant,
>
> Jack
   A couple of famous soft focus lenses work on this 
principal, for instance the Cooke soft focus lens which is 
again being made (but very expensive). These were orginally 
made by Taylor Taylor and Hobson. My memory is that this 
lens works by moving the center element.
   Triplets are very sensitive to element spacing but there 
are sucessful front element focusing Triplets so that may 
not work for getting a good soft focus effect. Some 
experimenting can be done by shimming the various elements 
to vary them. Unscrewing the front cell will move both front 
and center elememts together in most, if not all, Triplets, 
nonetheless, its very simple to do and won't hurt the lens.
---
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com