gelatin filters

[Anita Gould]

In article <9411181801.AA06074 at fcs260c2.ncifcrf.gov> pnh at ncifcrf.gov writes:

   Al McGraw (mcgraw at BSCR.UGA.EDU) wrote:

   | I wonder if filters for regular EtBr-UV photography are available at a 
   | similarly low price from a camera shop.  Our camera rig has two filters
   | in it - I'm not sure what they are - but they're so old scratched and
   | smudged that image quality suffers.  Any suggestions?  Paul?

   Yes. They are Kodak Wratten Gelatin filter No. 2B and No. 23A.

   -Paul.

I hate to tell you this: I was just in the camera shop a few days ago
& thought I would replace our similarly scratched filters, but the
salesperson told me that Kodak doesn't make a 23A or 22A any more.  He
seemed to know what he was talking about, & looked it up in the
catalog as well.  He wasn't able to tell me what I should use instead
-- any ideas?  I didn't want to just match the color of the filter by
eye, since I know that different spectral band-pass properties can
give the same visible color.
--

                                   -Anita Gould
                                    anita at cco.caltech.edu