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Old July 6th 08, 10:14 AM posted to uk.sci.astronomy
Chris.B
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Posts: 595
Default eclipse trip query

An astronomical thread? Good grief!

If you get involved in telescopes you need a steady tripod as well.
Which usually means heavy! I used my little 90mm Vixen refractor and
heavy Bogen video tripod for the last solar eclipse. I took pictures
with a handheld digital camera held up to the low power eyepiece.
(26mm and 15mm) Getting the kit to the top of the nearest grassy hill
to catch the event rather low in the very early morning sky was hard
work.

I hadn't bought my even smaller Bresser Skylux 70mm back then but it
is far too reflective internally (before modification) for Solar work
and the equatorial mounting is far too heavy for air travel and has no
electric drive anyway. A simple home-made cannon-style Dobsonion altaz
fork mounting made of thin plywood and balsa might work resting on a
wall with a borrowed Chinese brick, boulder or sandbag for a
counterweight. But the Bresser Skylux will need very careful internal
blackening to make it worth taking. Otherwise it's not a bad little
scope with the addition of some better (more expensive) eyepieces. You
could carefully remove the massive dewshield to save a lot of wasted
space in your luggage then it would go in almost any suitcase.

If you just take your binoculars make sure you have some spare Baader
solar filters and store them so they can't be damaged by other things
in your luggage. I'd suggest you put them into a cardboard tube with
easily removable ends something like poster packing. Put something
soft between each filter to stop them rubbing together under
vibration. One of my home made telescope filters has worn through the
reflective coating of the foil where it meets the dewshield and needed
local repair with black tape. I should have used a simple cardboard
ring spacer inside the filter to avoid this happening. I now store my
solar filters in clear plastic, screw top, kitchen storage containers
to keep them safe when not in use.

If you are taking a digital camera have spare *fully charged*
batteries and a large enough memory card to be able to take lots of
highest res snaps without changing cards. Make absolutely sure that
your batteries work well before leaving. Recharge and discharge them a
number of times to check for total reliability. There are some garbage
(even big name) batteries out there. I bought some spare Sony
batteries for the Mercury transit and the damn things wouldn't hold a
charge from new! £18 for two AAs! So I was limited to a pair of dying
batteries for a once in a lifetime event! Use a standard slow
charger to avoid frying your batteries. My Cannon paving-slab-style
battery seems to last for months. I bought a spare and have only ever
done one battery swap (from memory) in six months despite taking
pictures every single day.

Set your camera to highest resolution and switch digital zoom off in
the menu so you are not tempted to use it. Steady the camera on
something to take sharp, useful shots which can be enlarged later at
the computer. Zooming digitally to take large fuzzy images is a total
waste of effort. Use only optical zoom. You can set your camera to
hold the lens out without auto retraction it will avoid wasting time
waiting for it to "wake up" between shots. You could even make a
little push-on Baader filter for the camera if you can safely fix the
lens in the extended position in the menu. See how it copes being
pointed straight at the Sun without a filter but don't leave it for
too long.

Remember that you only get one chance at an eclipse. There are no
action replays. Practice a lot before before you go and have your
backup kit ready to hand and practice with the stuff you are actually
taking. Practice with the sun at the same height it will be on the big
day. Discovering that you need a shade or baseball hat for your head
in the middle of the eclipse is far too late. Have a lanyard for your
glasses or sunglasses so you can drop them onto your chest without
having to think about putting them down to use the binos or camera.
Discover how long the cord needs to be before you leave. If you wear
glasses think about how you are going to handle that problem before
you go. Most people don't need their glasses when using binos. Do you?
You may be like me and need glasses to see the camera viewfinder
screen clearly. If you are swapping between camera and binos you need
to practice that too.

Know *exactly* how high the sun will be during the eclipse before you
go. So you will be prepared for continuous viewing at that viewing
altitude. Find something to rest your elbows on while seated if
possible so you have a nice steady view without tiring your arms. A
tree, pole, chair, gate or fence can be used to support the arms or
camera if necessary. A hotel sun lounger or garden chair (with arms)
might be all you need depending entirely on the height of the sun
during the eclipse. If all else fails sit on the ground with your
elbows on your knees to support the binos or camera.

An eclipse is magical! Enjoy your trip. But do practice before you go
to avoid disappointment.