[APML] No Exposure (Was: Frozen Cameras)

["Kevin Wigell" <kwemail@twcny.rr.com>]

----- Original Message -----
From: "John C. Mirtle" <jmirtle@shaw.ca>
To: <astro-photo@seds.org>
Sent: Tuesday, December 10, 2002 21:26
Subject: Re: [APML] Frozen Cameras


> Roland;
>     Here's a good habit that you might want to get into. After you start
an
> exposure, and you have guiding under control, have a look through the
camera
> viewfinder. If you see stars, advance the frame, set the shutter to 'B'
and
> start again. It saves a lot of grief!

Count me as one of those who has fallen victim to this same stupid error.
Since then, I've gotten into the habit of carefully listening to the sound
the shutter makes when I trip it. The sound is distinctly different on my
OM-1 when the shutter opens and stays open (i.e., "B" setting) than when it
opens and quickly closes (i.e., any other setting). Practice with it a few
times with no film in the camera, and you'll hear the distinct difference.

This also helps prevent another stupid error on my part, namely forgetting
to pull out the "flip" mirror on my Taurus Tracker OAG before starting an
exposure. If I forget to pull back the mirror, and then look through the
viewfinder after tripping the shutter, I still won't see any stars because
the OAG's flip mirror is blocking light to the camera. So in this case,
looking through the camera's viewfinder doesn't verify the shutter is open.

So now my routine whenever I start an exposure is - listen to the sound the
camera makes, then visually check the flip mirror to make sure it has been
withdrawn.

Kevin Wigell
www.kwastronomy.com


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