[APML] Re: Film Tests

["westergren" <westergren@netzero.net>]

Jerry,

Well ... yes.

I regard PPF400 as one of the best films I have shot.  But I started
shooting astro pictures in 1997, so I may have missed some earlier good
films.  The color balance of PPF seemed good to me so I used it as my
reference.  I have found a lot of films considered to be poor for astro work
that measure very high in one color (usually green) or very low in another
(usually red).  Having a film with "even bars" on my graphs indicates the
same color balance as PPF at 1 second.  Finding a film with higher bars is
what we are all looking for.

Don

From: "Jerry Lodriguss" <jml@astropix.com>


> Hi Don,
>
> Reading your pages on your film hypering tests, I can across this:
>
>  >"Having all the color bars at the same level will produce the most
accurate
>  >colors. "
>
> I'm not sure having all the bars equal will produce the most accurate
> colors.  I think that all that will do is most closely match the hypered
> PPF color for a 1 second exposure, don't you think?
>
> Jerry
>
>
>
>
> Astronomical photography: http://www.astropix.com
>
>
>
>



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