Re: [APML]: Exposure confusion- HELP!

[Jerry Lodriguss <jml@astropix.com>]

At 05:44 PM 1/4/80 -0500, you wrote:
>
>Not sure if this can be resolved.  I shot half a roll of Ektachrome P1600
>(my very first astrophotos) and impatiently cut off the piece and took it in
>for dev.  I told them it was shot at 1600, but afterwards, no one could tell
>me whether it was pushed x2 as per instructions to get 1600, or not.  So I
>don't know whether it was done at 400 or 1600.

>Milky Way through Cygnus, very dark skies:
> 21mm lens f3.5 10min. excellent exp. black background
>135mm lens f2.8 7min. excellent exp. black background
> 50mm lens f2.8 7min. excellent exp. black background *** all exp. almost
>identical.


When you say f/3.5 do you mean REALLY f/3.5 (which is 2/3 of a stop slower
than 2.8, or do you mean f/3 and a half... one half stop click between f/2.8
and f/4, which is a half stop. Lots of people (me included) sometimes say
3.5 when we mean 3.4 and yes, I'm quibbling here... :-)


I shot some P1600 last year in Arizona, very dark skies.

Cygnus to Cepheus Milky Way
35mm lens f/2.8, 24 min, black sky background but what I'd call slightly
underexposed (but I usually go to sky fog limit and the sky isn't black then).

My film was developed at EI 400.

My best guess is your film WAS developed at 1,600.

Here is a simple way to find out. What did they charge you for developing
the roll? You probably paid extra for the push.

Jerry
email: jml@astropix.com 
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