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Brunton 20x70mm Lite Tech binos
by Chuck Hards 28 Jun '04

28 Jun '04

They arrived on Friday. Too bad the entire weekend was cloudy! I did get in some daytime use however. These are nice binos and will work well for astronomy. The water/fogproofing is a nice feature for a large binocular also. 20x magnification makes a tripod or parallelogram mandatory. Since these are "closeout" binos and no longer made, I won't write a full review, just give them a "thumbs up" recommendation. But I'm glad I got them, I will be selling another binocular to make room for them in my arsenal. They are definitely "keepers". Order fast, Sportsmans Guide has limited quantities. __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - 100MB free storage! http://promotions.yahoo.com/new_mail

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Eyepiece evaluation
by Chuck Hards 28 Jun '04

28 Jun '04

Critically evaluating your own eyepieces is easy. Focus the eyepiece and examine the image. * Are the stars sharp points all the way from center to the edge of the field? If not, can you sharpen the edge of field stars by re-focusing slightly? If so, then the focal plane is curved. This could be an artifact of your objective, not necessarily the eyepiece. Try other eyepieces to try and determine which it is. * If the stars cannot be sharpened to points by refocusing, examine them closely. If the stars have little "wings" on them, you have a comatic image. If the star stretches out to a straight or slightly curved line that changes orientation by about 90-degrees as you move from one side of focus to the other, astigmatism is suspected. * Examine a fencepost or phone pole during the daytime through the telescope. As you move it from the center of the field to the edge, does it appear to bend inward or bow outward? If so, this indicates curvature of field and this is usually an eyepiece abberation. * Estimate how far from the center of the field the above abberrations begin to show up. If you don't see stretched, squashed or flared stars until you are almost to the very edge of the field, the eyepiece is pretty good. If it starts only a third or halfway out, the eyepiece has issues. Curvature of Field and Astigmatism are the biggest eyepiece offenders and easily checked for. These are the characteristics that most often determine if an eyepiece is "good" "bad" or "marginal". Spherical abberration and chromatic abberation are uncommon in eyepieces these days and typically indicate a sub-par objective, especially if a doublet refractor or undercorrected Newtonian. But if you notice spurious color that is not apparent in other eyepieces used with the same objective, these can be suspected. "Ghosts" are internal reflections, usually seen when a bright object is off-axis slightly. Modern camera lenses are notorious for ghosting, as are eyepieces with many elements. High price is no guarantee that the eyepiece will be ghost-free. This is usually an annoyance on planets, and during imaging only, and rarely seen when looking at the faint fuzzies visually. The above elements are there for anybody to see who looks through the eyepiece, and not really arguable. Eye relief and apparent field, on the other hand, while definitely properties that make an eyepiece easier or harder to use, are personal prefference items that will vary from individual to individual. * Eye relief can be judged on ease of use. Is there enough "breathing room" between your eye and the glass, or is your eye uncomfortably close to the eyepiece when in use? Eye-relief can be measured with a metric ruler by focusing on the moon, then measuring the distance from the glass to the round, tight "exit pupil" disk as seen on a card. Move it until the smallest diameter is achieved, then measure the distance. Usually, anything over about 18mm is considered "generous" and essential for eyeglass wearers. If it's under 12mm then it's considered on the tight side. EVery visual prescription is slightly different so what you need in the way of eye relief may be different from what your buddy needs. * Remember that as magnification increases, exit-pupil diamter decreases. For this reason, even those individuals with severe astigmatism can probably get along fine without their glasses at very high powers. We are only using the very center of our pupils in those cases and the "barrel correction" for astigmatism usually isnt needed. Try taking off your glasses for exit pupils below about 3mm, you may be pleasantly surprised. Exit pupil is determined by dividing the aperture of the telescope (in mm) by the magnification. The resulting approximation is the diameter of the exit pupil in millimeters. Evaluating eyepieces is a tad more involved than just looking at the image and making an aesthetic judgement. Wide-field has nothing to do with image fidelity and often contributes to abberrations, so judge critically and don't let yourself be "wowed" soley by the composition. Have fun, be honest with yourself, and good luck! __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - Send 10MB messages! http://promotions.yahoo.com/new_mail

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Eyepiece comparison
by Jim Gibson 28 Jun '04

28 Jun '04

When I first got interested in stargazing, I took a telescope making class from Brent Watson. In teaching us about the optic train Brent stressed how every piece of glass inserted in the light train has an effect on what we see and that we would be handicapping ourselves if we built a great mirror and then didnt get good quality eyepieces. In a short time of research on the web, right or wrong, it seemed apparent to me that the standard for comparison in many cases was the Tele Vue Nagler eyepieces. It seemed to me that most folks were looking for the same quality eyepiece but for a cheaper price as the Negalrs tend to be expensive. At the time I was using a 5 Meade that came with 0.96 no-named Japanese eyepieces that were cheapies in order to keep the price in line with Wal*Mart standards. I got a 1.25 adapter from Meade and my first real quality eyepiece was a 13mm type 6 Nagler. I will never forget the experience of my first view through the Nagler after having become used to the 0.96ers. In bringing the moon into sharp crisp focus I was immediately stunned with the image before me and all I could do for the longest time as my eye traveled across the detail of the moons surface was to say to myself, Wow! Wow! Wow! I have since joined the throng of those looking for the Wow experience for a cheaper price. In my pursuit I have heard some good things about many eyepieces like University Optic Orthoscopics, which I managed to pick up a few. I recently bought a 15mm (1.25) eyepiece form Seibert Optics (http://www.siebertoptics.com/SiebertOptics-1.25in-eyepieces-ultra.html#15mm) and I also bought a 15mm and a 19mm (both 2) from Russell Optics (http://www.citlink.net/~optics/products.html) that were very reasonably priced; on sale at the time for $60.00 a piece where as the Siebert was about $150.00 I then asked our own illustrious Chuck Hards if he would evaluate them, and he graciously accepted the challenge. Following is Chucks evaluation. Keep in mind Chuck is only commenting on his experience with these individual eyepieces. Smaller companies may tend to have a somewhat larger variation in the quality of their output than a big company like Tele Vue has. So if some of you have one of these other eyepieces and really like yours, you may have a good one. I dont know enough about either company to make a judgment as to whether these individual eyepieces are representative of the companies standard output or not. I do value Chuck's many years of experience and his perceptiveness in all areas pertaining to astronomy. > > Chuck Hards wrote: > > Hi Jim: > > > > OK, here goes, while it's all still fresh in my mind. > > > > I used the Orion 80mm ED scope, on the Weightless > > mount. Both 50mm finder and a red-dot sight, > > Williams Optics 2" diagonal. > > > > TV Nagler 13mm type 6: Great imagery, no detectable > > abberations out to the edge of the immense field. > > Short eye relief, cannot see entire FOV with glasses > > on. Magification is low with the little refractor > > and this eyepiece, but it looks like my 12mm Konig is > > just as sharp and maybe a bit sharper, at the expense > of half the FOV. But the Nagler is a "Cadillac" of > eyepieces and there's no denying it. Sweet. [Chuck next looks a the Seibert ultra wide 15mm] > > Silver Eyepiece (marked only "15 U") 1.25" OD:a > nice eyepiece, although not a particularly wide > apparent field. Well-corrected out to near the very edge, > > fair eye-relief, the fold-down eyeguard is a boon to > > eyeglass wearers and allows the entire FOV to be > > taken-in with glasses on. Requires a lot of "in" > > travel, I was worried I'd bottom-out on my secondary > > mirror's surface and slid it into the diagonal > > carefully. But this eyepiece performs well, > > mechanics aside. I'd keep this one in my box if I didn't > have an obviously better one at the same focal length. > > You can feel good about this purchase. [Chuck now looks at the two Russell eyepieces] > > 15mm "Super-Wide" 2" OD: This eyepiece was > obviously not in the same class as the first two as soon as > I focused it. What appears to be strong coma is > > probably severe astigmatism in this eyepiece. Stars > > are stretched-out beginning only 1/2 way to the > edge of the field. The test for astigmatism is to watch > > > it change from a vertical slash to a horizontal > > slash as you rack through best focus. In a comatic > > condition stars would have "wings", flaring away > > from the center of the field. > > Eye-relief was too short to use with glasses and > > even uncomfortable without them. But the distortion > alone makes this eyepiece a big loser. > > > > 19mm "Super-Wide" 2" OD: Same general complaints > as the 15mm, but to a much lesser degree: I could > > almost live with this eyepiece, say on a large finder. > But not for any kind of critical viewing. > > > > The 15 and 19 are Russells, aren't they? They just > > go to show you that wide-field is no good if it's not > > sharp too. Sell them on-line or at the next > > swap-meet. Is the silver one a Siebert? That one's not bad at all. > > > > Thanks again for letting me play with these, it was > > fun and enlightening. > > > > C. --------------------------------- Do you Yahoo!? Yahoo! Mail - 50x more storage than other providers!

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dead list -- new TOPIC! SpaceShipOne
by James Helsby 24 Jun '04

24 Jun '04

So did anyone actually make it out to see the launch and return? I was reading on slashdot, yesterday, about the pilots experiences, and that her reported almost loosing control during decent. I also heard that NASA is talking about coughing up some cash to the winner of the X-Prize. So, is SpaceShipOne the clear leader? Or does you guys have other hunches as to who might win the Civilian Space Race (CSR for Short, and here in, /Copyrighted :-)) /Cheers, James.

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Discount codes
by Chuck Hards 23 Jun '04

23 Jun '04

Here are 2 discount coupon codes for Sportsmans Guide: SPG 1718 Expires 8/20 $5 off $49 purchase or more SPG 1498 Expires 8/06 $5 off $49 purchase or more Enter either in the appropriate box at checkout or mention it to the operator if ordering via telephone. Can only use one per order. __________________________________ Do you Yahoo!? Read only the mail you want - Yahoo! Mail SpamGuard. http://promotions.yahoo.com/new_mail

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Launch in ~20 minutes
by Patrick Wiggins 23 Jun '04

23 Jun '04

In the unlikely event anyone is reading this right after I send it, I just received email saying a Minuteman III is set to be launched from Vandenberg AFB (S. California) at about 02:01 this morning (Wednesday). If you've got dark skies and a low SW horizon, go have a look (I'm going to be up on my roof). Patrick

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Nice article in today's Desnews Joe
by Richard Tenney 21 Jun '04

21 Jun '04

FYI, an interesting article by Joe Bauman appears on the cover of today's Deseret morning news about the work Dr. Chan at the U is doing on mars "marbles" research. Way to make the front page Joe! __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - Send 10MB messages! http://promotions.yahoo.com/new_mail

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RE: [Utah-astronomy] Bryce Canyon Star Party
by Michael Carnes 21 Jun '04

21 Jun '04

Hey Don- It was a blast. Sorry I couldn't stay for the last night, but I realized during the day that my sleep deficit was increasing exponentially and I'd never catch up. Did anyone get pictures of that row of scopes? Michael -----Original Message----- From: "Don J. Colton" <djcolton(a)piol.com> Sent: Jun 21, 2004 9:48 AM To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> Subject: RE: [Utah-astronomy] Bryce Canyon Star Party Thanks to all who helped out at Bryce! We had mostly clear skies Thursday and spectacular skies both Friday and Saturday nights. The Milky Way in Sagittarius was as good as I have seen it in the Northern Hemisphere with good seeing fairly low in the sky. We had bacon wrapped filets, salads and cheesecakes at 1 AM and several of us stayed up all night Friday. The Rangers want to make it even better next year with the filets at 1 AM and omelets at 5 AM. Clear Skies Don Colton _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com

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Re: [Utah-astronomy] Rich's note and report on astronomy vacation
by UTAHDEB＠aol.com 21 Jun '04

21 Jun '04

Hey Joe, I have a few good observing spots in southern Utah. I like to stay away from I-15 because of the lights and other problems. There is a good spot near Rockville in a subdivision. We turn left on Anasazi Way and we drive to the end of the road where there is a cul-de-sac. I was out there in March with Jim Gibson, Jim Van Buskirk, and Jim Colwell. But it's getting quite hot now so we will probably head up towards Kolob Reservoir next month. That guy was probably up to no good because he sped away so quickly. That is why I go to Jim's house in LaVerkin when I'm by myself. It is much safer than Black Rock Rd. in AZ and darker. If you need Jim's phone number I can give it to you. Debbie ps I heard Wolf Hole in AZ is good also although I haven't been down there yet

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Re: [Utah-astronomy] Bryce Canyon Star Party
by UTAHDEB＠aol.com 21 Jun '04

21 Jun '04

Hi Don, I wanted to stay up too but I was getting tired after four nights of observing plus a night at Tuacahn, I was ready for some sleep. You made a believer out of me concerning the clear skies at Bryce. Next year I'll make the reservations three months in advance so I won't have any problems getting a room. There was a lot of nice scopes there including a 20" Obsession. Debbie

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