[APML] 35 mm Camera & Focuser

["Serge Theberge" <serge.theberge@wti.on.ca>]

I thought that this is as good a time as any to introduce myself to the
APML.  I joined last week at John Mirtle's recommendation. John has been of
tremendous help in getting me restarted in this great hobby after a 30-year
hiatus!  I dabbled in astrophotography this summer with my 1974 vintage C8
and a recently purchased Canon Coolpix 4300 on the C8's original wobbly
mount and screechy drive motors to take some pictures of Mars as souvenir of
this memorable year.  The pictures were definitely not the greatest, but
after massaging it in Registax, they  kind of look half-decent, enough
anyway to catch the astrophotography bug!  The problem was then to figure
out where to start.  I decided to join the Toronto chapter of the RASC and
started firing emails on the RASC mailing list for help to get started.
Many RASC members have been really helpful, and John in particular has
guided me through the tropical forest of equipment that there is out there.

To make the story short (at least shorter), here is my equipment list: 
- I am keeping my C8 f/10 tube for planetary photography (I might get
something else in the future, but for now it will have to do)
- I have ordered the Losmandy G11 mount with GOTO (John tried to discourage
me to buying the GOTO option, but I love toys...)
- I have also ordered the Vixen RS200 8" f/4 Newtonian with coma corrector
at John's recommendation for deep-space photography.

Next, and this is why I am seeking your advice, is the 35 mm camera and
focuser issue.  

- I have an old Canon AT-1 manual camera, but nothing on it is
removable/interchangeable. One option with it would be to get the Stiletto
Series IV focuser. However, I am concerned about getting the focus error
within tolerance, which, according to Covington's book, should be within
.04mm to 08mm for an f/4 scope.  I am concerned (maybe wrongly) that it may
be a bit much to expect everything to stay put within 40-80 microns while
unmounting the focuser and mounting the camera.

- Another option would be to buy a used Olympus OM-1 for which there seems
to be more options.  I found a used one that comes with 2 shutter release
cables and a Beattie IntenScreen for $299CDN. I have no idea as to whether
this Beattie IntenScreen will be of any help for deep-sky observing.  John
suggested that if I take the Olympus road, I should consider getting the
Hutech circular knife edge. But again, it means unmounting and remounting
the camera.  

- John also suggested to consider getting the 6x30 Lumicon "critical focus
magnifiers" which can be mounted on the Olympus viewfinder by gluing the
Lumicon to the metal frame of the eyeguard, thus enabling it to be fixed to
the camera.  I must say that I find this non-swapping approach more
attractive.

- Finally, on a line of thought similar to John's Lumicon, the last approach
I found was from Scott Tucker's web site where he uses a Peake 22x loupe
mounted on a camera that has a removable finder. Neither my Canon or the
Olympus OM-1 have removable finders, which would therefore leave me to buy a
camera body such as a Nikon F series. Snooping around the APML archives, I
found a thread where Wil Milan states that "The F1 can work, the F2 and F3
are probably the best for pure astro work, the F4 can work well but is very
heavy and very expensive, the F5 would not be a good choice because it has
no manual (i.e., no-battery-drain) time-exposure mode as do the F1 - F4."

So this is where I stand right now in setting myself up for
astrophotography.  

I am looking forward to hearing your advice on this 35 mm camera and focuser
issue.

Thanks in advance,

Serge Theberge
Toronto Centre
RASC


_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo