Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site ucla-cs.ARPA
Path: utzoo!watmath!clyde!cbosgd!ukma!psuvm.bitnet!psuvax1!burdvax!sdcrdcf!ucla-cs!wales
From: wales@ucla-cs.UUCP
Newsgroups: net.astro
Subject: Halley's Comet (photos in Los Angeles)
Message-ID: <8367@ucla-cs.ARPA>
Date: Tue, 14-Jan-86 22:53:14 EST
Article-I.D.: ucla-cs.8367
Posted: Tue Jan 14 22:53:14 1986
Date-Received: Fri, 17-Jan-86 01:57:58 EST
Reply-To: wales@ucla-cs.UUCP (Rich Wales)
Distribution: net
Organization: UCLA Computer Science Department
Lines: 50

Last Friday, I photographed Halley's Comet in the Los Angeles area.
I am posting the details in case they may be helpful to others who
may try to see, and/or take pictures of, the comet when it reappears
in March.  I would also welcome any suggestions for improvements in
my technique.

DATE/TIME OF SIGHTING:  10 January 1986, approx. 1845 PST
                       (11 January 1986, approx. 0245 UTC)

PLACE OF SIGHTING:  In the hills near Malibu, CA (about 20 km west of
    Los Angeles).

CONDITIONS:  Sky was perfectly clear.  Very slight wind.  Some lights
    from the few houses in the area.  Could see stars down to about
    4th or 5th magnitude with the unaided eye.

LOCATION OF COMET:  Approximately 21h 57m RA, -4d 30' Dec (2000.0;
    based on comparison of photos with Tirion Sky Atlas).

MAGNITUDE OF COMET:  Between 5 and 6 (based on comparison of comet
    image with nearby stars on photos).  I could not see the comet with
    the naked eye, but I could see it in 7x50 binoculars or telescope.

CAMERA:  Pentax MX body, 50mm f/2 lens (no filter -- not even a skylight
    filter); mounted piggyback on a Meade 2080 scope with motor drive
    and dual-axis drive corrector.  Lens was focused at infinity with
    the lens wide open.

FILM:  Stock (unhypered) Fujicolor 1600 color print film.

EXPOSURE:  From 8 seconds to 8 minutes, in multiples of 2.  (8-minute
    exposures were best; 4-minute were OK; others probably not worth
    the effort in this case.)

ALIGNMENT OF TELESCOPE:  I do not have a special polar axis finder.  I
    aligned the telescope by sighting down the barrel, and fine-tuned
    the motor drive rate by watching Jupiter for several minutes (using
    an illuminated-reticle eyepiece).  The pictures showed no noticeable
    streaking (of course, by the nature of the technique they were wide-
    angle, so this is not unexpected).

OTHER COMMENTS:  Most of the pictures had several airplane trails.  I am
    going to try to enlarge a portion of the best print (showing the
    comet, plus some nearby stars for location purposes); we'll see what
    happens.
--
Rich Wales // UCLA Computer Science Department // +1 213-825-5683
        3531 Boelter Hall // Los Angeles, California 90024 // USA
        ARPA:   wales@LOCUS.UCLA.EDU  -or-  wales@UCLA-LOCUS.ARPA
        UUCP:   ...!(ucbvax,ihnp4)!ucla-cs!wales