Re: Comet Hyakutake

[John W Roberts <roberts@xxxxxxxxxxxxxxxxx>]

>Date: Mon, 25 Mar 1996 09:17:29 -0600
>From: Joel.Alpers@xxxxxxxxxxx
>Subject: Re: Comet Hyakutake

>[Me]
>#The interval should depend on the magnification (if any) used. At 16x,
>#the comet moves noticeably with respect to the background stars in less than
>#half an hour.

>Unfortunately for photography, there's a real tradeoff between magnification
>and maximum exposure without star trailing. I've taken rolls of this thing
>so far, and my best results seem to be using a normal lens to just slightly
>telephoto (i.e 50-90mm) range. Much longer than that, and star trailing
>begins to be evident at fairly short exposures, and you lose comet
>detail.

The ideal solution is to clamp a camera onto a telescope with a motor drive.
Having gotten a better look at it since the previous post, I'd say that with
anything higher than "normal" FL, most of the tail would be chopped off.

>#>   For just viewing Hyakutake, 7X binoculars are great.  
>#
>#Direct viewing is also fine. The cloud around the nucleus is very distinct.
>#The tail is very faint (without a time exposure), but apparently that's stanard
>#for comets.

>Hate to keep harping on this, but get out to a dark site, the tail
>is very obvious to the naked eye.

Hey, I'm just glad I got to see it at all! Over the course of about two
weeks, I was in several parts of the country, and the sky was solidly
overcast every night wherever I went. Finally it cleared up on Friday night.

I agree that the tail is "very obvious", but it's also "very faint" compared
to the head of the comet, for instance. I tried some photos on Sunday night
with the less-than-optimim film that was in the cameras. If they turn out OK,
I'll confess what settings I used. :-)

John R


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