[pure-silver] Re: Some Edwal Patents

"Edward C. Zimmermann" <edz@xxxxxxx>

"Nicholas O. Lindan"
> "Richard Knoppow"
> > [H&W "Control" ... US Patents 3,772,019 & 4,083,722]
> Variations on POTA, but with magic claims.
The H&W Control is a little more than that-- and some of the "claims" are hardly "magic". 

From the patent description, though not in the claims:
"Ilford Pan F ... with the new developer of this invention exposures may be made at an exposure index (E.I.) of 400 ... with exceptional quality..." 

  "Tri-X with exposures ... at an E.I. of 4000
   ... with wide tonal range ..."
And this with POTA with a pinch of some variation on hydroquinone ... 

Sounds like magical thinking to me.

--
Nicholas O. Lindan
Cleveland Engineering Design, LLC
Cleveland, Ohio 44121

=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your 
account (the same e-mail address and password you set-up when you subscribed,) 
and unsubscribe from there.

Other related posts: