|
Check out the advice on
cleaning optics below. |
MISCELLANEOUS
THOUGHTS ON EQUIPMENT There are some good articles discussing
the various items a deep-sky observer may need. Dave Eicher's 1987 article is a
good general overview. Special categories of equipment are mentioned below.
Sinnott, R. W. (1996) [Tele-tips] Sky &
Telescope, March, 76; November, 86.
MacRobert, A. M. (1994) "The Modern
Astronomer's Red Light" Sky & Telescope, April, 49.
MacRobert, A.
M. (1993) "Backyard Astronomy: Keeping Warm Under Winter Stars" Sky &
Telescope, February, 28.
Eicher, D. J. (1989) "Don't Forget the Bug
Spray" [Be prepared for anything under the stars with these ten essential
items. Don't leave home without them!] Astronomy, August, 67.
Levy, D. H.
(1988) "Star Trails" Sky & Telescope, October, 418.
** Eicher,
D. J. (1987) "Gearing Up for Summer Deep-Sky Observing" Astronomy,
March, 64. [A good general discussion of all sorts of stuff you'd need for
observing.]
ASTROPHOTOGRAPHY
Bunge, R. (1992) "Nightscapes"
[Create stunning night-sky photos with no more than a camera, a tripod, and a
little imagination] Astronomy, June, 72.
Baumgardt, J. (1987) "Astrophotography
without a telescope" Astronomy, January, 46.
Willson, M. F. (1986) "Camera
lenses for Deep-sky astrophotography." Astronomy, August, 54.
There is an email-based discussion list for
astrophotographers, Astro-Photography Mailing List (APML), owned and
administrated by Gary Holland ([email protected]). It also has a web-based
archive, maintained by Andy Steere ([email protected]). To subscribe
to APML, send email to [email protected] and put "subscribe
astro-photo" (without the quotes) in the body of the message.
Their web
page is at:
http://www.system.missouri.edu/ics/staff/andy/APML/
BINOCULAR ACCESSORIES
Rogers, D. (1995) "Make a bino mount"
Astronomy, 23, 8, 71.
MacRobert, A. (1993) "In Search of a Good
Binocular Mount" Sky&Telescope, June, 35.
Wehler, R. (1993) "Build
a Reclining Binocular Mount" Sky&Telescope, April, 90.
Knott, M. L.
(1992) "Build a Universal Tripod" [Use this versatile sturdy tripod
with your binoculars, reflectors or refractors] Astronomy, August, 76.
Lewis,
R. C. (1991) "Build a Bino-chair" [For less than $75 this observing
chair will bring fun and satisfaction to your binocular observing] Astronomy,
December, 79.
Unruh, J. T. (1991) "An Altazimuth Sky Chair" Sky &
Telescope, November, 545.
Shumaker, B. P. (1988) "Build a Binocular Sky
Scanner" Astronomy, February, 64.
OBSERVING CHAIRS
Wolczanski, G. (1993) "Building an
Observing Chair" [You no longer need the grace of a ballet dancer to reach
your scope's eyepiece. This seat goes up and down to keep you comfortable while
you observe] Astronomy, November, 78.
Klein, K-H. (1991) "An Observing
Seat for Two Telescopes" Sky & Telescope, May, 544.
Stanbury, J. B.
(1990) "A Handcrafted Chair for Viewing Comfort" Sky & Telescope,
March, 328.
CHART TABLES
Letters: Astronomy, 23, 8, 12. [photo of a
portable observing easel]
Dagilis, D. (1994) "Build a table for your
star charts." [This table will keep your atlases and papers out of the dew
and protect them from a misguided footstep in the dark] Astronomy, May, 108.
MacRobert,
A. M. (1994) "A Table at the Telescope" Sky & Telescope, April,
47.
Smith, L. R. (1991) "An Observing Desk On-The-Go" [When you're
seated at the telescope, a pilot's kneeboard can serve as a lightweight portable
desk in the dark] Astronomy, November, 84.
COPING WITH DEW
Clark (1990) puts it quite bluntly: 'Dew is extremely hazardous
to optics'. Dewing occurs on surfaces that cool below the dew point, the
temperature at which evaporation no longer occurs. This causes water droplets to
condense on anything at, or below, that temperature. A classic example is the
film of water that appears on a glass of ice water on a hot day. Because of the
cold water, the air next to the glass is cooled to its dew point, so water in
the air condenses and clings to the sides.
The key to preventing dew is to keep the telescope's
temperature slightly above the dew point.
Hale, J. (1996) "Dealing with Dew"
In "Telescope Making", Sky & Telescope, January, 85. [Using
aluminum foil, and not heaters, to combat due]
MacRobert, A. M. (1995) "Dealing
with Dew" Sky & Telescope, June, 48.
Blackwell, S. K. (1992) "Make
Your Own Dew Eliminator" Sky & Telescope, October, 455.
Sinnott, R.
W. (1990) "Gleanings for ATM's: Warming a Dew Cap: Two Stories" Sky &
Telescope, December, 673.
MacRobert, A. M. (1990) "Ensuring a Dry Scope"
Sky & Telescope, November, 556.
Hammond, H. (1987) "Build a Heated
Dew Cap for Less than $10" Astronomy, November, 72. But see the corrections
in Astronomy Letters, 1988, February, p 32. Also: Astronomy Letters, 1988, June,
p 36.
Keith, L. (1985) "Build a $6 Eyepiece warmer" Astronomy,
April, 52
EYEPIECES
Clark (1990) recommends that eyepieces be protected by some
form of lens cover, like a plastic cap, or they should be kept in plastic
sandwich bags, before being stored in a safe case.
MacRobert, A. M. & Pepin, M. B. (1996) "S&T
Test Report: Your Basic Eyepiece Set" [We tested 31 low- to mid-priced
eyepieces for sharpness, contrast, field size, aberrations, light throughput,
and other attributes] Sky & Telescope, April, 38.
Dyer, A. (1993) "Choosing
Eyepieces: a buyer's guide" Astronomy, June, 56.
FILTERS
Harrington, P. (1995) "S&T Test
Report: Light-Pollution Filters" [Twenty years have passed since filters
were introduced to improve the contrast of deep-sky objects. But how well do
they really work? Observing expert Philip Harrington surveys the choices now
offered] Sky & Telescope, July, 38.
Ling, A. & Spevak, J. (1991) "Astronomy
Tests Ten Nebula Filters" [Of the many filters on the market all promise to
reduce the effects of light pollution and enhance deep-sky observing. We
fieldtested ten filters and found significant differences among them]
Astronomy, February, 74.
FINDERS
Regen, D. N. (1996) "A Look at Seven
Unit-Power Finders" Sky & Telescope, June, 48.
MAINTENANCE Your telescope's optics
need periodic maintenance. You'll need:
can of compressed air / lens-cleaning bulb
cotton balls
distilled
water
isopropyl alcohol
liquid detergent
towels
and a kitchen
sink
Cleaning a mirror
1. remove rings, chains, and
other loose stuff - you don't want to scratch anything.
2. cautiously remove
the mirror from the cell
3. carefully blow off any large particles of dirt
that may be on the mirror surface using the lens-cleaning bulb or a can of
compressed air. DO NOT use a brush of any kind.
4. lightly saturate some
soft cotton balls and very gently BLOT the surface to pick up other loose
particles of dirt and dust. Remember, you are cleaning a delicate surface, which
can be scratched quite easily.
5. rinse out your kitchen sink. Place a
folded towl inside, and then the mirror - shiny side up - on the towl.
6.
run room-temperature water over the mirror, to remove remaining dirt on the
surface.
7. rinse the mirror in distilled water, and let it dry by standing
it on its edge - use more towels, to prevent the tilted mirror from slipping.
8.
put a plug in the sink, keep the towel in the sink,and fill it with enough
luke-warm water to cover the mirror. Add a teaspoon of liquid detergent.
9.
put the mirror back in the sink, on the towel, and let it soak for a few
minutes.
10. after soaking, swirl the mirror around, keeping it submerged.
This will wash away any sizable dirt particles.
11. take a ball of
cottonwool, and swab the mirror surface, still underwater. Use an even straight
motion, starting at one edge of the mirror and moving gently across to the other
side. DONT put pressure on the cottonball; let the weight of the swab do the
work.
12. discard the cotton after each wipe, and make sure the following
wipe overlaps a bit.
13. examine the mirror for more dirt, and repeat if
necessary.
14. drain the sink, and rinse the mirror by letting luke-warm
water run over it for a minute.
15. drain the sink again, and give the
mirror a final rinse with distilled water.
16. as in (7), let the mirror
drip dry again.
17. replace in cell and telescope, and enjoy the crisp
views.
Cleaning a refractor objective, or eyepieces Cleaning
eyepieces is a lot like cleaning mirrors, just on a smaller scale.
1. clean
the lenses in place - DO NOT remove the refractor's objective, and DO NOT
disassemble the eyepieces.
2. prepare a solution of three parts distilled
water and one part isopropyl alcohol. Add one drop of liquid detergent for each
QUART of the solution.
3. use compressed air or blower brush to remove large
particles of gunk.
4. put a drop of cleaning fluid on a cottonwool ball and
lightly swirl it onto the lens.
5. DO NOT pour the solution direclty onto
the lens; the fluid may seep into the lens housing.
6. use another
cottonwool swab to clean the lens with a gentle circular motion, swabbing the
lens surface as you go.
7. use a third cottonwool ball to dry the lens off.
Cleaning a SCT corrector plate
1. clean the correct
plate in place - DO NOT remove it.
2. prepare a solution of three parts
distilled water and one part isopropyl alcohol. Add one drop of liquid detergent
for each QUART of the solution.
3. use compressed air or blower brush to
remove large particles of gunk.
4. put a drop of cleaning fluid on a
cottonwool ball and start cleaning from the centre: use smooth, even strokes. DO
NOT apply pressure on the cotton swab as you move straight out from the centre
to the edge.
5. ensure each subsequent stroke overlaps slightly with the
previous one; discard the cottonball after each wipe.
6. finally, dry the
plate with fresh cottonwool patches.
Adapted from
Porcellino, M. (1992) "How
to clean your optics." [Remove dust and dirt from your mirrors, lenses and
eyepieces. It'll make a big difference in what you see with them.] Astronomy,
March, 81.
Similar advice was posted to the sci.astro.amateur newsgroup by
[email protected] (b.alex.pettit.jr):
From:
[email protected] (b.alex.pettit.jr)
Newsgroups: sci.astro.amateur
Subject:
Re: Mirror Cleaning
Date: 22 Feb 1998 11:33:58 GMT
I made cleaning solution of
60water/40isopropyl; maybe 2 oz in all with 1 drop of liquid soap. DON'T use off
the shelf stuff - get medical grade to ensure no contamination. Ask your Dr. or
Vet. for a 'prescription' for sterile water and 100% isopropyl alcohol...
I
started with the water,alcohol,soap mix, dabbed it on gently with cotton balls
to wet the surface well, and then used a cotton ball for each small wipe of the
lens until it had all been cleaned twice.
Then switched to 50/50 alcohol and
water for a rise, and then to pure isopropyl. The last should be quicky applied
and then dried with fresh cotton in long swirling motions. Gotta get the surface
dry before it spots. There are a few very minor streaks near one edge, but I
found I could never get rid of all of them : I just wound up chasing them from
one place to another. I probably used half of the roll of raw cotton, but its
cheap.
MOUNTS
Siers, J. (1994) "Improving your mount"
[constructing a permanent pier] Astronomy, December, 66.
McGraw, T. (1994) "Improving
your mount" [Add circles to your Dob] Astronomy, December, 66.
Knott,
M. L. (1992) "Build a Universal Tripod" [Use this versatile sturdy
tripod with your binoculars, reflectors or refractors] Astronomy, August, 76.
Shaffer,
R. (1988) "The Mount of Gibraltar" [Make your telescope mount as solid
as a rock by filling the tripod head with epoxy resin and adding leg braces]
Astronomy, August, 64.
OBSERVATORIES
Krick, J. (1992) "Building Owl
Observatory." Three-part series. Astronomy, 1: April, 2: May, 3:June.
Chomniak,
S. (1989) "Build a Backyard Observatory" Astronomy, June, 90.
TELESCOPES
MacRobert, A. M. (1995) "Star-Test Your
Telescope" Sky & Telescope, March, 42.
Bruning, D. (1994) "Test
your scope's optics" [Here's how to use a star at night - or an
easy-to-build artificial star - to evaluate the performance of your telescope]
Astronomy, July, 56.
Dickinson, T. (1993) "S&T Test Report:
Low-Cost Telescopes" Sky & Telescope, December, 59.
Ceravolo, P.,
Dickinson, T. & George, D. (1992) "Optical Quality in Telescopes"
[We test the conventional wisdom about how good an amateur telescope's optics
really need to be. The results will surprise you] Sky & Telescope, March,
253.
Porcellino, M. (1992) "How to Collimate Your Telescope" [Is
your telescope producing images that resemble bloated butterflies? Solve the
problem with this straightforward technique of telescope collimation] Astronomy,
April, 60.
Dyer, A. (1991) "Astronomy Tests affordable reflector
telescopes" [We tested 12 Newtonian reflector telescopes, each costing less
than $ 1000. We found several good choices for an entry-level scope, including a
couple of bargains. We also found some lemons.] Astronomy, December, 68.
Ling,
A. (1990) "Ten tips for improving your telescope." Astronomy, August,
66.
Knott, M. L. (1989) "Sharpen Images with a Cardboard Mask" [A
simple mask on your reflector produced cleaner images of double stars and
planets] Astronomy, February, 84.
Shaffer, R. (1988) "Soup Up Your
Small Scope" [Rev up the performance of your telescope with accessories
like high-quality eyepieces and a good finder scope] Astronomy, September, 80.
Monaghan,
R. (1987) "Building Fun Telescopes for Less than $10" Astronomy, May,
46.
Bird, K. (1986) "Building a Copyscope" Astronomy, May, 74.
Uselton,
T. (1985) "The Dobsonian dolly transport system" Astronomy, June, 75.
Eicher, D. J. (1984) "How to Choose a Deep-Sky Telescope"
Astronomy, October, 75. |
