From: owner-utah-astronomy-digest@lists.xmission.com (utah-astronomy-digest) To: utah-astronomy-digest@lists.xmission.com Subject: utah-astronomy-digest V1 #30 Reply-To: utah-astronomy-digest Sender: owner-utah-astronomy-digest@lists.xmission.com Errors-To: owner-utah-astronomy-digest@lists.xmission.com Precedence: bulk utah-astronomy-digest Monday, March 12 2001 Volume 01 : Number 030 ---------------------------------------------------------------------- Date: Fri, 2 Mar 2001 15:31:41 -0800 (PST) From: Richard Tenney Subject: (utah-astronomy) Dakins found Some of you have asked me about Mark; I managed to make contact with him today. I have his new e-mail and phone numbers if anyone is interested. Rich. __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Fri, 2 Mar 2001 22:38:56 -0700 (MST) From: Joe Bauman Subject: (utah-astronomy) aperture Dear friends, I am considering (someday) upgrading so that I can do photography better than with my 8" Celestron SCT. I would appreciate hearing from y'all on this question: assuming a refractor is too expensive, what's the next best buy, a reflector or an SCT or something else? I didn't buy a reflector in the first place, when I got started with astronomy years ago, because I thought reflectors would need to be open to the air and that dust, moisture, etc., could easily damage the mirror. Was I wrong on that count? Thanks, Joe Bauman - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 07:25:13 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture Joe, this is one of those questions where you'll get a different answer from everyone you ask. What kind of photography are you planning? What kind of image scale? What size format? The mounting is as important a question as the telescope. What are your portability requirements? The Schmidt-Cass is still the all-around best combination of portability and versatility, most owners feel that this offsets the less-than-perfect imagery, I might even agree three days out of five. Mirror coatings last for decades if properly cared for. My 10" mirror was last aluminized in 1982, and it is still very usable. Longevity here is mostly up to you. Assuming the refractor is too expensive, stick with the C-8. Chuck - --- Joe Bauman wrote: > Dear friends, I am considering (someday) upgrading > so that I can do > photography better than with my 8" Celestron SCT. I > would appreciate > hearing from y'all on this question: assuming a > refractor is too > expensive, what's the next best buy, a reflector or > an SCT or something > else? I didn't buy a reflector in the first place, > when I got started > with astronomy years ago, because I thought > reflectors would need to be > open to the air and that dust, moisture, etc., could > easily damage the > mirror. Was I wrong on that count? Thanks, Joe > Bauman > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 09:36:04 -0600 From: Joe Bauman Subject: Re: (utah-astronomy) aperture Thanks! How do you care for the 10" mirror? Is it exposed when you use it? Do you then clean it after every observation session? I really want something better than 8" for photography, but don't know when I'll upgrade or what to get. -- Joe - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 08:30:15 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture Joe, a Newtonian mirror actually gets much better protection than the front surface of a refractor,or Schmidt-Cass corrector plate, due to the main tube, which is in effect a loooooong dewcap. I keep my tubes covered when not in use. The dustcaps must be tight-fitting to keep out dust, yet be breathable to allow moisture to escape. A baggy and rubber-band can give further protection to the secondary, with a little bag of silica gel tossed in, but this usually isn't neccessary if the main tube is covered correctly. Store your tube in a horizontal position. This places the main mirror in a vertical orientation, and less dust will settle on it when stored. NEVER store a reflector upright! Also, rotate the tube so the secondary faces downward, keeping dust off of it, too. After bringing in the scope from outdoors, let any dew or frost evaporate or sublimate away before you cover it up. I usually let my mirror fan blow for a few minutes indoors, to speed up the drying-out process. Mirrors only need serious cleaning every few years if taken care of properly, and this is the timetable I observe. I do NOT clean the optics after each use. No need. BTW, a little dust won't harm the image; even a seriously dirty mirror looks worse than it usually is. There has to be a lot of dirt before you notice the contrast loss and diffraction effects. If you practice good maintenance, covering and storing as indicated, you'll never see that kind of build-up. If there is sufficient interest, I may put on a mirror-cleaning demonstration at a club meeting one of these days. We could set up a "seminar", and have members bring in their dirty optics for cleaning and adjustment. Chuck - --- Joe Bauman wrote: > Thanks! How do you care for the 10" mirror? Is it > exposed when you use it? > Do you then clean it after every observation > session? I really want > something better than 8" for photography, but don't > know when I'll upgrade > or what to get. -- Joe > > > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 10:33:11 -0600 From: Joe Bauman Subject: Re: (utah-astronomy) aperture Thanks, Chuck, That's quite interesting. I would love to see a seminar. What do you think of the value of a 12" reflector (say) vs. 8" sct for photography of galaxies? I really appreciate your info. -- Joe - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 09:48:51 -0700 From: "Larry Frisk" Subject: Re: (utah-astronomy) aperture Chuck, If you have a cleaning seminar I would like to attend. I really enjoy the messages and comments of all of the participants of this group. I'm not smart enough to contribute but I have been sponging up a lot of interesting stuff. Larry - ----- Original Message ----- From: "Chuck Hards" To: Sent: Monday, March 05, 2001 9:30 AM Subject: Re: (utah-astronomy) aperture > Joe, a Newtonian mirror actually gets much better > protection than the front surface of a refractor... . - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 11:58:03 EST From: RStmarie@aol.com Subject: Re: (utah-astronomy) aperture - --part1_7c.127225cd.27d51f9b_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Chuck and Joe, I've been reading the mail here and am interested also in buying a new scope. I lean hard toward a SCT for all the reasons Chuck mentioned earlier. Basically it is a good compromise. Aperture is a must, more is better, but I have heard 10" is about as large as a single guy can lug around and easily set up alone. Have either of you guys heard anything about the new Celestron GPS 11"? Big, built light, with a carbon fiber-epoxy tube, computer aiming, and connections built in for accessories later, like ccd cameras and such. I've talked with a guy who said he gets lots more use out of a smaller scope that is more portable. Interested in your thoughts and opinions... Bob St. Marie - --part1_7c.127225cd.27d51f9b_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit Chuck and Joe,  I've been reading the mail here and am interested also in
buying a new scope.  I lean hard toward a SCT for all the reasons Chuck
mentioned earlier.  Basically it is a good compromise.  Aperture is a must,
more is better, but I have heard 10" is about as large as a single guy can
lug around and easily set up alone.  Have either of you guys heard anything
about the new Celestron GPS 11"?  Big, built light, with a carbon fiber-epoxy
tube, computer aiming, and connections built in for accessories later, like
ccd cameras and such.  I've talked with a guy who said he gets lots more use
out of a smaller scope that is more portable.  Interested in your thoughts
and opinions...  Bob St. Marie - --part1_7c.127225cd.27d51f9b_boundary-- - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 09:41:35 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture Bob, I'm not much of a bells-and-whistles guy (unless I made it myself) but I've heard the same good things about that scope. Too, I can't see why a healthy adult of average stature couldn't handle an 11 or 12-inch Schmidt-Cass with little trouble. Chuck - --- RStmarie@aol.com wrote: > Chuck and Joe, I've been reading the mail here and > am interested also in > buying a new scope. I lean hard toward a SCT for > all the reasons Chuck > mentioned earlier. Basically it is a good > compromise. Aperture is a must, > more is better, but I have heard 10" is about as > large as a single guy can > lug around and easily set up alone. Have either of > you guys heard anything > about the new Celestron GPS 11"? Big, built light, > with a carbon fiber-epoxy > tube, computer aiming, and connections built in for > accessories later, like > ccd cameras and such. I've talked with a guy who > said he gets lots more use > out of a smaller scope that is more portable. > Interested in your thoughts > and opinions... Bob St. Marie > __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 09:44:06 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture Thanks for thinking that the participants are smart. Truthfully, we're just the ones who can't shut up. ;) Chuck - --- Larry Frisk wrote: > Chuck, > If you have a cleaning seminar I would like to > attend. > I really enjoy the messages and comments of all of > the participants of this > group. I'm not smart enough to contribute but I have > been sponging up a lot > of interesting stuff. > Larry > > ----- Original Message ----- > From: "Chuck Hards" > To: > Sent: Monday, March 05, 2001 9:30 AM > Subject: Re: (utah-astronomy) aperture > > > > Joe, a Newtonian mirror actually gets much better > > protection than the front surface of a > refractor... > . > > > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 09:50:22 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture All other things being equal, I'd take the 12. Aperture rules, especially if you want to shoot the faint fuzzies. Note that a 12" Newt poses a much more daunting mounting problem than an 8" SC, however. Portability will mean (much)more physical exertion with the Newt. The compromise, of course, is an 11" SC, as Bob is thinking.... If/when I get my observatory built, my instrument of choice will undoubtedly be a large Newtonian, since portability won't be an issue. But I still will have a battery of smaller scopes of various sizes and configurations, for star-parties, camping, etc. Chuck - --- Joe Bauman wrote: > Thanks, Chuck, That's quite interesting. I would > love to see a seminar. > What do you think of the value of a 12" reflector > (say) vs. 8" sct for > photography of galaxies? I really appreciate your > info. -- Joe > > > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 09:57:52 -0800 (PST) From: Chuck Hards Subject: (utah-astronomy) Congrats to local Messier Certificate recipients! I want to congratulate local amateur astronomers Joe Borgione and David Croft for getting mentioned in the new issue of the REFLECTOR (Feb. 2001), for earning their MESSIER CERTIFICATES. Way to go, guys! Chuck __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 05 Mar 2001 11:26:18 -0700 From: Patrick Wiggins Subject: Re: (utah-astronomy) aperture You know Joe, you could just wait until SPOC 2 is done and then shoot images with the .95 m (37"). :-) Patrick Joe Bauman wrote: > > What do you think of the value of a 12" reflector (say) vs. 8" sct for > photography of galaxies? - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 05 Mar 2001 11:40:19 -0700 From: Patrick Wiggins Subject: (utah-astronomy) Re: aperture > ...but I have heard 10" is about as large as a single guy can > lug around and easily set up alone. I'll agree that "the bigger the better" but will also note that the easier a scope is to move about and set up the more it will get used (one of the reasons why my C-14 which is always set up and ready to go gets used a whole lot more than my C-8s which I have to drag out and set up). Also, I tend to question buying a 10 vs an 8 when I don't know that the relatively small increase in light gathering ability is worth the extra bulk and cost. > Have either of you guys heard anything > about the new Celestron GPS 11"? I believe one of our members has one on order. The thing I like about it is the internal GPS and electronic compass. Having those two items negates the problem we saw at the star party Saturday where owners of current generation goto scopes could not get set up until it was dark enough to see acquisition stars. Heck, if the system works you could switch the system on anywhere on the planet in the middle of the day and the scope would still align itself. Patrick :-) - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 11:00:02 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture - --- Patrick Wiggins wrote: > You know Joe, you could just wait until SPOC 2 is > done and then shoot images > with the .95 m (37"). :-) True, but he'd have to stand behind me in line and wait his turn! (that's going to be one popular instrument) But your comment brings up a good point, Patrick. I bet soon the board will have to put a committee together to award telescope time based on project merit, and dark-sky requirements. Chuck __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 5 Mar 2001 11:07:47 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) aperture - --- Patrick Wiggins wrote: > You know Joe, you could just wait until SPOC 2 is > done and then shoot images > with the .95 m (37"). :-) True, but he'd have to stand behind me in line and wait his turn! (that's going to be one popular instrument) But your comment brings up a good point, Patrick. I bet soon the board will have to put a committee together to award telescope time based on project merit, and dark-sky requirements. Chuck __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 05 Mar 2001 12:42:48 -0700 From: Patrick Wiggins Subject: (utah-astronomy) Re: Aperature time Chuck Hards wrote: > > I bet soon the board will have to put a committee > together to award telescope time based on project > merit, and dark-sky requirements. Actually it's already happened. The U has expressed interest in getting time (possibly in return for lab fees) so a committee is being formed to look into the idea of allotting time. Patrick :-) - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 6 Mar 2001 09:30:14 -0600 From: Joe Bauman Subject: (utah-astronomy) Re: aperture To continue the discussion about the economics of astrophotography, can anyone tell me the pros and cons of a Schmidt camera? Also, how much weight does one lug around with a Newtonian of 12 inches or so? It's not that I have anything particular in mind, but I thought if I ever upgraded it would have to be something like that to get much of a benefit. -- thanks, Joe - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 6 Mar 2001 08:35:06 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) Re: aperture - --- Joe Bauman wrote: > To continue the discussion about the economics of > astrophotography, can > anyone tell me the pros and cons of a Schmidt > camera? Wide field, fast system (short exposures). Not good for high-powered or planetary photography. (Image scale too small) Usually employed as "survey" cameras, or "patrol" cameras. > Also, how much weight > does one lug around with a Newtonian of 12 inches or > so? A visual Newtonian of 12" aperture could be built quite light, less than 30 lbs if you went with a truss-tube. A PHOTOGRAPHIC capable system could conceiveably weigh hundreds of pounds, mostly in the mounting. Joe, you probably can't beat a good Schmidt-Cass or Mak system for all-around portability and versatility, especially for photography. That said, many of the top photographers who do use SCT or Mak optics often replace the factory mount, finding it lacking for those "magazine cover" shots. Chuck __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 6 Mar 2001 14:35:54 EST From: RStmarie@aol.com Subject: Re: (utah-astronomy) Re: aperture - --part1_3c.855fee4.27d6961a_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Isn't a Dob just a Newt on a lazy susan? A 12" newt of average focal length is going to be ... long. I am guessing 6 or 7 feet long. Got a pickup truck? - --part1_3c.855fee4.27d6961a_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit Isn't a Dob just a Newt on a lazy susan?  A 12" newt of average focal length
is going to be ... long.  I am guessing 6 or 7 feet long.  Got a pickup truck?
- --part1_3c.855fee4.27d6961a_boundary-- - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 6 Mar 2001 11:57:18 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) Re: aperture Bob, you're absolutely right, but you don't need a 12" to have a long scope....a 6" f/10 can easily reach six feet long. This is the same problem that refractors have in the larger apertures (cost aside) If compactness and portability are your prime requisites, it's hard to beat a SCT. Maybe a folded refractor, but it'l still be longer than the SCT in most cases. Remember that the Newtonian's biggest advantage is ecconomy. The design gives you the most aperture for unit cost. It also gives you large physical size, and unfortunately, the larger the mirror, generally, the poorer the quality. I'd venture a guess that all those big, thin mirrors out there are just BARELY diffraction-limited, if at all. But they are light-buckets in general, not astrometric instruments or instrument carriers, so most are suited perfectly to their purpose. The ideal telescope has been described as "large aperture, small physical size; perfect, unobstructed optics, and low cost". Good luck finding that one! Chuck - --- RStmarie@aol.com wrote: > Isn't a Dob just a Newt on a lazy susan? A 12" newt > of average focal length > is going to be ... long. I am guessing 6 or 7 feet > long. Got a pickup truck? > > __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 06 Mar 2001 14:11:29 -0700 From: Patrick Wiggins Subject: (utah-astronomy) Re: aperture I love my 14 cm Schmidt camera. But then I also love my 200 mm f/16.8 refractor. Alas, for the most part neither are very practical. In the case of the refractor, it cost too much and it's so big it's a pain to transport. As for the Schmidt, it works great on large targets (Holly and I shot a whole slew of Hale-Bopp shots and put them together into a really neat movie) but small scale items just don't work since it's only got a 230 mm focal length. However, if you really want to get one, I do know of a 200 mm Celestron, brand new, still in the box that a guy in Oregon has been trying to sell me. Price: TBD Patrick :-) Joe Bauman wrote: > > To continue the discussion about the economics of astrophotography, can > anyone tell me the pros and cons of a Schmidt camera? - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 06 Mar 2001 23:06:00 -0700 From: Patrick Wiggins Subject: (utah-astronomy) HP, SPOC 2, New pix Yet more news about Hansen Planetarium (will it ever end?): http://deseretnews.com/dn/view/0,1249,255010752,00.html?textfield=Planetarium http://deseretnews.com/dn/view/0,1249,255010751,00.html?textfield=Planetarium SPOC 2 update: Bruce Grim, Roger Butz and I went to the site late tonight and surveyed the north / south line for the building and piers. Think we got it right? :-) New pictures: Remember Hale-Bopp? It may be 2 billion kilometers from Earth but it's still being watched: http://planet.state.ut.us/pix.html And here are a couple of images taken with the ST-6B I'd like to sell: http://planet.state.ut.us/slas/patrick/patrick.html , images 12 & 13 - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Fri, 9 Mar 2001 11:05:14 -0800 (PST) From: Chuck Hards Subject: (utah-astronomy) Solar spectroscope I have been wanting to build a visual solar spectroscope for some time, as an inexpensive alternative to commercial H-a filters for viewing prominences and other solar detail. The design is simple, anyone can make one for a few bucks. Just this morning, I was informed by Jack Newton that Coronado Instruments is coming out with their own version at around $800. This is still pricey, though cheaper than current H-a passband filtered units. One advantage of a grating-based unit is broadband tunabilty, much wider than a temperature-controlled filter. Personally, I'd have to see the view myself before commenting on the price. H-a filtered units typically have much larger fields of view than slit-type spectroscopes, so you have to decide for yourself if the view is worth the bucks. Anybody on the list ever build a solar spectroscope? How about a spectrohelioscope, with oscillating slits? I'd love to hear about it. Thanks Chuck __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Fri, 09 Mar 2001 13:16:57 -0700 From: "Brent Watson" Subject: Re: (utah-astronomy) Solar spectroscope CHuck, You compare this spectroscope to a H-alpha viewing device. Perhaps I am = missing something here, but doesn't a spectroscope allow you to look only = at spectra, and not an image? The H-alpha device would allow direct views = of the Sun, and hence the two seem to be very different beasts. What am I = missing here? Brent >>> chuckhards@yahoo.com 03/09/01 12:05PM >>> I have been wanting to build a visual solar spectroscope for some time, as an inexpensive alternative to commercial H-a filters for viewing prominences and other solar detail. The design is simple, anyone can make one for a few bucks. =20 Just this morning, I was informed by Jack Newton that Coronado Instruments is coming out with their own version at around $800. This is still pricey, though cheaper than current H-a passband filtered units. One advantage of a grating-based unit is broadband tunabilty, much wider than a temperature-controlled filter. Personally, I'd have to see the view myself before commenting on the price. H-a filtered units typically have much larger fields of view than slit-type spectroscopes, so you have to decide for yourself if the view is worth the bucks. Anybody on the list ever build a solar spectroscope?=20 How about a spectrohelioscope, with oscillating slits? I'd love to hear about it. Thanks Chuck __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail.=20 http://personal.mail.yahoo.com/=20 - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.c= om" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 12 Mar 2001 06:28:24 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) Solar spectroscope Hi Brent: Good question. When you view the prominences with a grating, you are looking at only a very narrow portion of the spectrum, not the whole thing. The effect is rather like an objective-prism used on planetary nebulae, that is, the image of stars and other broad-spectrum targets gets smeared out, where planetary nebulae, shining at a specific frequency, are imaged crisply. The same thing happens with prominences in H-a light, viewed with one of these spectroscopes. Chuck - --- Brent Watson wrote: > CHuck, > > You compare this spectroscope to a H-alpha viewing > device. Perhaps I am missing something here, but > doesn't a spectroscope allow you to look only at > spectra, and not an image? The H-alpha device would > allow direct views of the Sun, and hence the two > seem to be very different beasts. What am I missing > here? > > Brent > > >>> chuckhards@yahoo.com 03/09/01 12:05PM >>> > I have been wanting to build a visual solar > spectroscope for some time, as an inexpensive > alternative to commercial H-a filters for viewing > prominences and other solar detail. The design is > simple, anyone can make one for a few bucks. > Just this morning, I was informed by Jack Newton > that > Coronado Instruments is coming out with their own > version at around $800. This is still pricey, > though > cheaper than current H-a passband filtered units. > One > advantage of a grating-based unit is broadband > tunabilty, much wider than a temperature-controlled > filter. Personally, I'd have to see the view myself > before commenting on the price. H-a filtered units > typically have much larger fields of view than > slit-type spectroscopes, so you have to decide for > yourself if the view is worth the bucks. > Anybody on the list ever build a solar spectroscope? > > How about a spectrohelioscope, with oscillating > slits? > I'd love to hear about it. > > Thanks > > Chuck > > __________________________________________________ > Do You Yahoo!? > Get email at your own domain with Yahoo! Mail. > http://personal.mail.yahoo.com/ > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. > > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. __________________________________________________ Do You Yahoo!? Yahoo! Auctions - Buy the things you want at great prices. http://auctions.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Mon, 12 Mar 2001 06:28:39 -0800 (PST) From: Chuck Hards Subject: Re: (utah-astronomy) Solar spectroscope Hi Brent: Good question. When you view the prominences with a grating, you are looking at only a very narrow portion of the spectrum, not the whole thing. The effect is rather like an objective-prism used on planetary nebulae, that is, the image of stars and other broad-spectrum targets gets smeared out, where planetary nebulae, shining at a specific frequency, are imaged crisply. The same thing happens with prominences in H-a light, viewed with one of these spectroscopes. Chuck - --- Brent Watson wrote: > CHuck, > > You compare this spectroscope to a H-alpha viewing > device. Perhaps I am missing something here, but > doesn't a spectroscope allow you to look only at > spectra, and not an image? The H-alpha device would > allow direct views of the Sun, and hence the two > seem to be very different beasts. What am I missing > here? > > Brent > > >>> chuckhards@yahoo.com 03/09/01 12:05PM >>> > I have been wanting to build a visual solar > spectroscope for some time, as an inexpensive > alternative to commercial H-a filters for viewing > prominences and other solar detail. The design is > simple, anyone can make one for a few bucks. > Just this morning, I was informed by Jack Newton > that > Coronado Instruments is coming out with their own > version at around $800. This is still pricey, > though > cheaper than current H-a passband filtered units. > One > advantage of a grating-based unit is broadband > tunabilty, much wider than a temperature-controlled > filter. Personally, I'd have to see the view myself > before commenting on the price. H-a filtered units > typically have much larger fields of view than > slit-type spectroscopes, so you have to decide for > yourself if the view is worth the bucks. > Anybody on the list ever build a solar spectroscope? > > How about a spectrohelioscope, with oscillating > slits? > I'd love to hear about it. > > Thanks > > Chuck > > __________________________________________________ > Do You Yahoo!? > Get email at your own domain with Yahoo! Mail. > http://personal.mail.yahoo.com/ > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. > > > - > To unsubscribe from utah-astronomy, send an email > to "majordomo@xmission.com" > with "unsubscribe utah-astronomy" in the body of > the message. > For information on digests or retrieving files and > old messages send > "help" to the same address. Do not use quotes in > your message. __________________________________________________ Do You Yahoo!? Yahoo! Auctions - Buy the things you want at great prices. http://auctions.yahoo.com/ - - To unsubscribe from utah-astronomy, send an email to "majordomo@xmission.com" with "unsubscribe utah-astronomy" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ End of utah-astronomy-digest V1 #30 *********************************** - To unsubscribe to $LIST, send an email to "majordomo@xmission.com" with "unsubscribe $LIST" in the body of the message. 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