Re: [APML] New Illford Black & White film

[Matthew Hunt <mph+ap@wopr.caltech.edu>]

On Mon, Sep 24, 2001 at 07:54:02PM -0500, Robert Reeves wrote:

> > > Has anyone tried the HP Delta 400 B&W professional film? It looks to
> > > have spectral sensitivity well past H-alpha.

[...]

> I looked at this film when I was testing a lot of films for my book
> "Wide-Field Astrophotography"
> This film has perhaps the worst reciprocity failure of any I have tried.  It
> is terrible.  It sounds good from the sensitivity standpoint, but the lack
> of reciprocity overpowers the film and makes it useless for
> astrophotography.

This film was updated within the past year; did you test the new
version, or the old one?

The new formulation is getting good reviews for non-astrophotography,
apparently having a higher true speed than its predecessor or other
films labeled 400.  Don't know whether the reciprocity is any better.

-- 
Matthew Hunt <mph@astro.caltech.edu> * Science rules.
http://www.pobox.com/~mph/           *

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