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Re: photo strategies for Leonids '00? (was Re: (meteorobs) DMS ready for tak...

Hi Bob,
Well, you can always 1. Stop the lens down and double the exposure, which
will screen out fainter meteors and still show the big ones. 2. You could
use B&W and a yellow filter, since the sky is blue in moonlight this would
cut the Moon's contribution (I know, not publishable...). 3. Something
nobody has mentioned: Go for altitude. The higher you go the less scatter
you'll get. The White Mountains which are only a 5 or 6 hour drive from S.C.
will get you 14,000+ and I guarantee the sky is quite dark even with
moonlight - if you can breath and stay awake, that would be my choice. Half
the atmosphere is below you and also the most scattering dusty layers are
below. Rob's ideas are good...look and decide if there is enough activity to
warrant exposing. That way you don't waste film. You might ask Msr. Royer
how dark it is up there as he has gone there many times to photograph.
(email address from me if you don't have it).
Take oxygen.
Cheers
John
----- Original Message -----
From: <GeoZay@aol.com>
To: <meteorobs@jovian.com>
Sent: Friday, November 10, 2000 7:59 AM
Subject: Re: photo strategies for Leonids '00? (was Re: (meteorobs) DMS
ready for tak...


>
>
> >> I would like your input (& from anyone else) on *strategies* for
> photographing
> the Leonids, with the last-quarter moon near the radiant.<<
>
> In a nutshell....avoid pointing camera towards the moon. Aim in a
direction
> where the moon isn't. Screw the radiant.
>
>  >>At 1st, I figured meteor photography was an impossibilitiy, given the
moon
> interference.  So, I decided not to do anything for 2000 Leonids.<<
>
> Don't know what your purpose is for meteor photography, but if you are
> looking for the "perfect" picture, you may be out of luck. If gathering
data
> is your purpose, then there should be no major problem really....still
avoid
> pointing a camera towards the moon. If you use color film, the pleasing
> effect will probably experience some washout. I prefer black and white
film.
> I use to have a camera running for meteor captures even during a full
moon.
> I'd use HP-5 film using a 28mm f/2.8 lens. and develop for an ASA
equivalency
> of 400. I'd make exposures no longer than 10 minutes for a full moon. I'd
get
> some dense negatives, but they were useable for what I wanted them for at
the
> time. With a quarter moon, 10 minutes will probably be reasonable,
although
> you'll get some fogging the closer the camera's field of view is near the
> moon. I'd always aim my camera in a northerly direction since there was a
> darker part of the sky in that area. Always managed to get some useful
meteor
> photos where measurements could be made. My two wide angle cameras were
> guided on a camera platform. The tracking was usually good for at least 20
to
> 30 minutes before film advancement had to be made. But with the moon, 10
> minutes is useable if for strictly meteor measuring purposes. But you
> probably won't win any photo contests with the moon in the way.
>
>  >>I guess I could back-off, & use less cameras.  But, that compromises my
> blanket
> approach ("covering the sky")<<
>
> That would make sense and save you some money. Aiming a camera directly at
> the moon for meteor photography isn't gonna reap you very many useful
meteor
> images. Stars will be washed out etc. If you aren't gonna get anything
useful
> aiming a camera at the moon, why worry about a blanket approach? Aim the
> cameras where they will do the most good....unless you enjoy wasting time,
> effort and film?
>
> >>3) use big aperture scope (to get meteors, since point-source exposures
are
> function of aperture), with slow f-ratio (to "knock down"  sky-background
> fog).
> But, this means very long focal-length lenses.  This minimizes chances of
> getting
> meteors.  Contradiction.  Paradox.  No solution?<<
>
> Probably a waste of time.
>
> >>For 1), has anyone come up with a formula (ASA, f-ratio, lens diameter,
> exposure
> time), that is sky-background limited for half-moonlit conditions?  I can
> figure
> this out, by just going out & testing (long trip, hassle, $$, etc.)<<
>
> If you are looking for that perfect picture....your best bet would be long
> trips, hassle, $$ and lots of luck.
>
> >>(example)
> The Geminids '98, had a crescent moon come up in the east, ~4am.
>
>  I backed off my exposures to 5 min (instead of 15 min, moonless sky),
1000
> ASA,
> f2.8.  But this year, there will be a half-moon, so I would have to go
less
> exposure.  2 min?  3 min?<<
>
> Use slower film...try 400 ASA....you can photograph the moon with ASA 400
as
> well as 1000. Again, don't aim at the moon unless you want to let fate and
> luck take over and see if anything unusual might happen in your favor.
>
> >>Given the predictions, what are the chances of "fireballs" for 2000?
('98
> was
> noted for the quantity of fireballs.  see
> http://www.comet-track.com/meteor/leonids98/leonids98.html).  '99 was
> disappointing..I spent all that $$, the photos paled in comparison to
'98.<<
>
> Don't expect 2000 to be another 98. The fish you pull out of a pond won't
be
> there the next time you go fishing.
> GeoZay
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