[APML] Fun with a digital camera

[Robert Reeves <reeves10@swbell.net>]

Greetings everyone,

Regarding the images I have been doing with my new Olympus C3020, I got
things solved with my ISP (actually I have two of them, one for DSL, the
other hosts my web site) and can upload again.  I haven't had time to code a
web page, but here are links to the images on the server.

These moon shots from Sunday morning were all taken with an old orange tube
C-8  that I have used just as a guide scope for many years.  I think I
violated every high resolution astrophoto rule in the book taking these.
The corrector hasn't been cleaned in at least 10 years, its never been
colimated, there was dew on the corrector when I was shooting, seeing was
horrible, and I was hand-holding the camera at the eyepiece.  In spite of
that, I am tickled to death with the images.  I took others just after
Christmas, but will wait to post them when I can make up a web page with the
proper technical identifying info.

Parts of these images are not quite as sharp as other areas in the same
image.  This is partly seeing as waves of turbulance would sweep across the
moon.  It looked like ripples across water.  Also, hand-holding the camera
makes it tough to keep the film plane in line with the projected image.  I
am going to get one of those digital camera to eyepiece adapters reviewed
recently in S&T to fix the latter problem.

But in spite of the crude system, shoot enough images and a couple will come
out OK.  So here they are.

www.robertreeves.com/north   the northern area of the terminator last Sunday
www.robertreeves.com/center  the central area of the terminator
www.robertreeves.com/south   the southern terminator
www.robertreeves.com/ptolome closeup of the Ptolomeus crater area
www.robertreeves.com/3rdquar  full view of the 3rd quarter moon
www.robertreeves.com/termintr   "panorama" of the full length of the
terminator

And a couple of shots from earlier in this lunation

www.robertreeves.com/fullmoon  what it says... the full moon
www.robertreeves.com/luna1       random closeup
www.robertreeves.com/luna2       another undocumented closeup.

Whether it is a full globe shot or a higher power closeup, I have been using
only a 40 mm Meade 4000 eyepiece.  I vary the field of view by using the
camera's zoom lens.  I can get higher magnifications using my Brandon
eyepieces, but with some vignetting from the narower apparent field of view
through these eyepieces.

After focusing the scope by eye with my glasses on, I let the camera's
autofocus refine the image.  I also use aperture priority with the aperture
locked at f/2.8 and let the camera's meter set the exposure time.  At the
ISO 400 equivalent setting, exposures have been in the 125th to 800th second
range, depending on how bright the lunar feature is in the metering box.

One thing I keep forgetting is to disable the camera's flash.  I remember
after the first shot <G>

As descent as these images are, there is room for much imediate improvement.
Simply clean and colimate the old C-8 would help a lot.  Mounting the camera
on a tripod at the eyepiece will help with the problem of keeping it square
with the eyepiece (untill I get the afocal coupler).  And the need for
better seeing is a given.

But all in all, it is fun to be able to do some astrophotography from the
driveway at home without having to travel out of town.

Enjoy the images.

Robert Reeves                      reeves10@swbell.net
520 Rittiman Rd.                   www.robertreeves.com
San Antonio, Texas 78209    210-828-9036
USA                                     29.484  98.440  200 meters


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