I had a similar problem with some photo's I took over the weekend of the
milkyway. I used an Olympus OM-1 with a 28mm lens at f/2.8 and Fuji 800
speed film. All shots were made with the camera on a photo tripod and were
from 20-35 seconds long. When I got them developed at the local Costco 1
hour photo center none of the shots turned out!! Including a very nice (I
thought) shot of a double Iridium pass, along with a carefully composed shot
of my scope with the milkyway in the background, and Jupiter and Saturn near
the Pleiades.

I've checked the camera and it works fine!! Nothing is sticking or slipping,
and I had doublechecked all my lens, F/ratio settings, bulb setting etc.
before taking the shots. However all the frames (except a few dayshots) seem
to be underexposed, I've taken similar shots before on 400 and 800 speed
film before with great results and even had the same lab develop them. What
happened??? any thoughts would be appreciated, should I turn to a different
photo lab? if so which one? Can the films sensitivity degrade under moderate
heat? I had spent most of the day traveling out to the desert, but the car
remained fairly cool even when the AC wasn't on, and the camera and case
were never exposed to direct sunlight!

Thanks for the help

Howard


>Subject: Re: [M]: OT - Astrophotography problem
>Date: Wed, 2 Aug 2000 14:35:56 -0400
>
>Andy,
>You were most likely underexposing. Exposures of 5-30 seconds aren't going
>to pick up much of anything on 200 speed film unless you're shooting bright
>solar system objects. Even M42, the Orion Nebula, takes about 12 minutes
>with 200 speed film at f/10 (closer to 4 minutes at f/6.3). Michael
>Covington has a very nice little exposure calculation utility that you can
>download from his web site:
>
>http://www.covingtoninnovations.com/astro/
>
>You might also want to pick up a copy of his book, "Astrophotography for
>the
>Amateur Astronomer, 2nd Edition." You'll find it a tremendous help in
>getting started.
>
>================================================
>Ray Porter
>Applications Analyst Programmer
>Administrative Information Services, UNC-CH
>Phone: 966-5878
>Home Page: http://www.unc.edu/~dragon/
>
>"Meddle not in the affairs of dragons,
>for thou art crunchy and taste good with ketchup."
>
>
>----- Original Message -----
>Sent: Wednesday, August 02, 2000 2:17 PM
>Subject: RE: [M]: OT - Astrophotography problem
>
>
> > "black" in the sense that the slides were transparent with no hint of
>the
> > subject in them
> >
> > -----Original Message-----
> > Sent: Wednesday, August 02, 2000 11:50 AM
> > Subject: Re: [M]: OT - Astrophotography problem
> >
> >
> > Andy:
> >
> > Another question...when you say the frame were "completly black", do you
> > mean
> > BLACK as in if you took a photo of something black, or "black" in the
>sense
> > that
> > the slides were transparant with no hint of the subject in them?
> >
> > John
> >
>
>

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