Volume XXXII Issue 2
In this issue:
Pegasus is a bimonthly publication of the Berks County Amateur Astronomical Society
Editor/Desktop publisher: Melody Gardner
E-Mail submissions may be made to: email@example.com
Slate of 2006 Club Officers
President — Dave Brown
Vice President — Bret Cadmus
Trea$urer — Linda $en$enig
Secretary — Barb Geigle
Webmaster — Mike Bashore
Hot tub Coordinator — Paul Becker
Public Relations — Barry Shupp
Various & Sundry Items — Moi
Our Astronomy club has 2 items of interest coming up soon that we hope you will enjoy, and we would like to hear from everyone who would like to participate.
First, we have planned a group field trip to Cherry Springs State Park in Potter County, Pa. For those of you unfamiliar with this place, it boasts one of the darkest night skies east of the Mississippi. The "Milky Way" is breathtaking! Your telescope or binos will allow you to see sights you didn't think possible. Don't just take my word for it; ask any BCAAS member who's been there.
The trip will be an overnight event, leaving Saturday morning, April 22, returning Sunday the 23rd. Going as a group, we can carpool people and equipment, share tents or the cost of a hotel room for those who don't care to rough it, and beginners can learn from the experienced ones the best way to enjoy a fantastic night sky.
As a "suggested" time frame for this, if we leave at 10 AM Saturday, stopping for lunch enroute, arrival time at the park would be about 3 PM. (4 and a half hours actual drive time) Setting up camp and gear by 5 pm, supper (camp style) at 5:30, and catch a few z's till dark around 8 pm. (Daylight savings time has started) Sleeping late Sunday after filling your head with stars, we pack up, leave around 11 am, returning by 4 pm.
All this is dependent on a CLEAR weekend. We haven't planned a rain date, so we will make a go-or-no-go decision by Wednesday evening.
What we would like from YOU is to tell us if you want to go along on this trip. There are about 12 folks going as of this writing, and we want you to join us. As you can see, by going as a group the cost is minimal. You can contribute gas money if you want, or drive your vehicle and have someone else share the cost, share a tent, food, sleeping bags, etc. The cost to stay at the park is only 4 dollars.
Second item is starting a telescope mirror making group. Recently, our club was gifted a supply of optics and assorted equipment to make and polish our own telescope mirrors. Now don't think that you can only buy a good mirror, you can make a fine telescope mirror right in your own garage that rivals any store bought one. Several of our members have done it; you can too.
We also acquired some refractor lenses that would make great telescopes, so we have the possibility to build whole telescopes of several varieties using "off the shelf" materials.
What we would like from you members on this subject is 2 things. First, who would like to join in this project? Second, who knows a PLACE where we can make these mirrors and scopes? We need a garage or basement that we can set up, work on (say) a weekly basis, and leave materials there ‘till the project is completed, which may take some time. We don't need a LOT of space, but somewhere dry and safe would work.
If any of this interests you, let me know. Better yet, attend the next club meeting. We have some great programs on tap. Together, we can enjoy this hobby more than by ourselves.
Lets make some memories.
Dave Brown, BCAAS president
So You’d Like To Take An
By BL Shupp
If you’ve ever wanted to get out and take a photo of the night sky, now is the best time. Winter skies afford an excellent opportunity to obtain some really good astrophotos. What will you need?
The basics include an adjustable camera with time exposure settings, a locking cable release, and a sturdy tripod. I recommend 400 speed print, or slide film which will bring out many colorful stars in the clear winter skies. An older non-electronic shutter camera is best, but if you use one with a battery operated shutter, make sure to have a spare battery along with you. This time of year warm clothing is a necessity, including warm socks and shoes. I try to work without gloves, but a light cloth pair can be helpful if the temperature is low.
Attach the cable release to the camera after loading it with 400 speed film, and making sure that the film advances properly. The procedure to follow is to lock your camera on the tripod and set the focus to infinity. Make sure to remove the lens cap especially if you have a separate viewfinder from the picture taking lens. To make the exposure- cover the front of the lens with your hand and open the shutter. Have the cable release set to lock the shutter open when you press the plunger. Remove your hand from the front of the lens and time the exposure. (By holding your hand in front of the lens you minimize effects of camera or shutter vibration when the shutter is opened) I usually just count in my head for shorter exposures. After the time is up cover the lens again and close the shutter. Advance the film slowly to the next frame.
What can be photographed now? This is my favorite time of year for astrophotography because of the clear, non-humid skies, offering unparalleled views of Orion, the Pleiades, and the planets. A good starting subject might be a star trail of a major constellation like Orion. It is a large constellation and will fill the frame of a 35 mm picture using a normal lens.
A star trail occurs when you record the stars light on the film for more than the maximum time given in the table below. Instead of getting a point source of light the image forms a continuous line or arc on the negative as the Earth (and camera) rotate beneath the starry sky.
For a star trail, lock the shutter open with a cable release, and expose for 15 seconds to several minutes depending on how dark your site is. To do a static photo without trailing, expose for 20- 30 seconds with a normal lens. The multi-colored stars of Orion will make a nice photo. You might even catch a stray meteor cutting through the scene. The Pleiades is another good subject as the multiple stars in close proximity will occupy a large portion of the frame. Right now there is a fairly bright comet in the morning sky near Venus. It is visible in binoculars or perhaps naked eye but is small in size. 400 speed film should pull it out of the sky nicely, and with Venus in the shot, you should have a very nice photo. For comets, expose from 15 seconds up to 1 minute for the best rendition. Several planets currently dot the night sky, including Saturn, and Mars. Mars is near the Pleiades and they will make a nice pairing in your photo. Saturn is currently east of Orion near Sirius.
To talk a little bit more about exposure times we need to consider the Thousand Millimeter (MM) Second Rule. To get your exposure time for any lens, divide 1000 MM by the focal length (in millimeters) of your lens to get the time in seconds that you can expose without showing trailing. For a 1000 MM lens you would have- 1000MM divided by 1000 MM for a value of 1 second. Other combinations are:
50 MM lens- 20 seconds 20- 35 seconds
100 MM lens- 10 seconds 10- 15 "
500 MM lens- 2 seconds. 2- 3 "
The numbers in the second column show the range you can use and still get photos with only slight trailing. You can shoot wide open (aperture), or stopped down a bit for increased edge sharpness. Under slightly windy conditions a weight tied to the center post of the tripod can stabilize the equipment to prevent blurring.
Static shots and star trails of constellations and planets are only some of the pictures you can take. Comets, and auroras are infrequent visitors to the night sky and make excellent photo subjects. The Moon especially in eclipse can be an inviting target for your camera. The book "Astrophotography For The Amateur" by Michael Covington is an excellent resource which I have used for many years. Also, feel free to email me at firstname.lastname@example.org with any questions you may have on photography of the night sky. And stay warm!
Still under Construction
BCAAS General Meeting— Thursday, March 9 at 7:30pm—Dr. Devon Mason, a professor of physics at Albright College, speaking on "Search for Extraterrestrial Intelligence: ET phone us, we'll do lunch".
BCAAS Starwatch -Saturday March 25 - 7pm, hosted by Larry Citro at Larry's Home at Charming Forge near Womelsdorf. Check out Larry's website at www.starryforge.com
BCAAS General Meeting— Thursday, April at 7:30pm—Planetarium Show! ($5 adults & $2 kids)
Trip to Cherry Springs State Park.—Saturday April 22 - Sunday 23rd. The club will leave Saturday morning and observe and camp out at the park, then travel back on Sunday. Anyone wishing to join can contact Dave Brown.
Public Star Watch - Friday May 5 - 7:30pm at Kaercher Creek State Park . Rain date is Sat., June 3rd at 8:00pm.
BCAAS General Meeting—Thursday May 11 at 7:30pm— Steve Walters, entitled "High-Resolution Imaging - Climbing Mount Everest".
May 6 - May 7, 2006 - 15th Northeast Astronomy Forum http://www.rocklandastronomy.com/neaf.htm
June 22 - 26, 2006 - Tentative Cherry Springs Star Party http://www.cherrysprings.org/
July 28 - 30, 2006 - StellaFane Convention http://www.stellafane.com
August 25 - 27, 2006 - Black Forest Star Party http://www.bfsp.org/starparty
Oct 18 - 22, 2006 - Mason Dixon Star Party http://www.masondixonstarparty.org
Oct 20 - 22, 2006 - Stella Della Valley XX http://www.bma2.org/Sdv.html
Call our hotline at 610-921-0173 for the latest club events and meeting details!
"There is no adequate defense, except stupidity, against the impact of a new idea." Percy Williams Bridgman