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How
to View an Eclipse Continued
Pinhole images are pretty
dim and small. There's another projection method that uses a pair
of binoculars. DO NOT LOOK THROUGH THE
BINOCULARS!
(Click the image for expanded instructions)
1) First,
you should firmly fix the binoculars to a tripod. You can do this
with duct tape (what else?).
2) Cut out
a shield made of cardboard and tape it to the front of the binoculars
with the lenses sticking through holes that you cut.
3) Put the
lens cap over one of the large binocular lenses or tape over one
of the front lenses with duct tape. (You really only need a monocular
for this.)
(Click the image for expanded instructions)
4) Use the
duct tape to seal any holes that leak light past the cardboard.
5) Point the
binocular towards the sun while holding a piece of white cardboard
about a foot behind the eyepiece.
6) It will
take a little effort to find the sun. Once you do, you can focus
the binoculars to bring the sun to a sharp image.
Be careful
not to put your hand or anything flammable near the eyepiece!
The concentrated sunlight exiting there can cause a nasty burn
or set something ablaze!
Now you can
watch a beautiful, bright, magnified image of the sun as the eclipse
proceeds. You will have to adjust the tripod to account for the
earth's rotation. One possible warning here. You might give your
binoculars a cooling break now and then. The eyepiece may become
overheated and the lens elements may separate if you leave it
on the sun too long. You've been warned!
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If you feel that you just
have to look directly at the sun, be absolutely sure that you
have the correct filter. Just because a filter makes the sun seem
dim does not mean that it's blocking invisible infrared or ultraviolet
radiation that will certainly cause eye damage in short order.
Do not
use sunglasses, polaroid filters, smoked glass, exposed color
film, x-ray film, or photographic neutral density filters.
Make sure
that the supplier of your eclipse filter is reputable and reliable.
A few are listed below. You can, for instance, look at the sun
with a number 14 welders glass. Get this from a welding supply
store. Silver-based black-and-white photographic emulsions, when
exposed and developed fully can be used if you are experienced
and knowledgeable in this area. You might need several layers.
It's easier, though, to spend a couple of bucks on a filter you
know is safe. If you want to use a filter on a telescope, only
use the filter supplied by the manufacturer or by a manufacturer
who makes the filter specifically for the instrument you are using.
In some cases, this is bad advice.
| The
suppliers of some cheap refractors supply a welder's glass
filter that screws on to the eyepiece. DO NOT USE THESE!
They may heat up and crack as you are looking through the
telescope. A proper solar filter always goes on the front
end of the telescope, blocking the sunlight before it enters
the optical system. |
Do
not use this type of telescope filter:
(Click
the image to see a larger view.)
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By following
the instructions above and using a modicum of good sense, you
will be able to enjoy solar eclipse after solar eclipse. I have!
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Filter suppliers
from Fred Espenak's wonderful web site
<http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/safety.html>
Information about solar viewing from "Mr. Eclipse"
<http://www.mreclipse.com/Special/filters.html>
ABELexpress - Astronomy Division, 230-Y E. Main St., Carnegie, PA
15106. (412) 279-0672
Celestron International,
2835 Columbia St., Torrance, CA 90503. (310) 328-9560
<http://www.celestron.com>
Meade Instruments Corporation, 16542 Millikan Ave., Irvine, CA 92714.
(714) 756-2291
<http://www.meade.com>
Orion Telescope Center, 2450 17th Ave,, P.O. Box 1158-S, Santa Cruz,
CA 95061 (408) 464-0446
<http://www.telescope.com/interact/default.asp>
Thousand Oaks Optical, Box 4813, Thousand Oaks, California 91359 (805) 491-3642
<http://www.thousandoaksoptical.com/>
Rainbow Symphony, Inc., 6860 Canby Ave. #120, Reseda, CA 91335 (818)
708-8400
<http://www.rainbowsymphony.com/>
Assistpoint Limited, 40 Allendale Road, Barnsley, South Yorkshire, S75 1BJ, United Kingdom (tel) 0114 238 7569
<http://www.eclipseglasses.co.uk/>
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