Has anybody had success splitting these doubles?: Lambda Oph 52 Orionis 32 Orionis 36 Andromedae Zeta Bootis Lambda Cygni If so let me know the magnification and aperature. Thanks, Debbie
Deb, I have split 52 Orionis, 36 Andromedae, and Lambda Ophiuchi with my 10". I cannot recall the magnification, however. They are tight, but not exactly test doubles. The separations are 1.2, 1.2, and 1.5 second of arc. The aperture required for a split according to Dawe's Limit is only four inches for any of them. I list 32 Orionis as a test double. This is because it tests the seeing. At a separation of 1.1 seconds, it is still splitable in a 4.25 inch scope. The seeing will make it difficult, however. I have again split this fairly readily with my 10" Zeta Bootis is closer at only 0.8 seconds. The Dawe's Limit for a split on zeta is just undre 6" I have needed a significantly better night to split zeta in th 10". I have also done it with the 8" refractor. Now, if you want a real challenge, go after beta Delphini. It is listed at .65, but it was difficult at around 400 power in both the 10", the 9" Clark at Wolf Creek. Dawe's limit here requires at least 7". Brent --- UTAHDEB@aol.com wrote:
Has anybody had success splitting these doubles?:
Lambda Oph 52 Orionis 32 Orionis 36 Andromedae Zeta Bootis Lambda Cygni
If so let me know the magnification and aperature.
Thanks,
Debbie
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I'll start seeing what optics are available, and gathering materials. To keep costs down, we'll probably build a Plossl or true symmetrical. If I can find some inexpensive triplets, the ortho can be explored. I may be able to offer kits of both designs, wait and see. These "kits" will cost me about $15 each; is everyone who wants to participate able to pony-up fifteen bucks? I will make no profit on this endeavor, but must cover costs. Although we probably will NOT use wood for a housing, optically we will be building something similar to the "Homemade eyepieces" I described in S&T a couple of years ago (Feb. 00). Let me know if there are any particular questions you would like the speaker(s) to address. Thanks! C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Chuck- I'm interested in the proposed eyepiece seminar, and would gladly pony-up $15. I would like to have your speakers address the applicability of different designs of eyepieces for different telescope designs, such as very long vs.very short focal lengths. Which eyepieces offer the most benefit for a 20" f4, or a 8" f6, or a 4" f15? Bob Grant ----- Original Message ----- From: "Chuck Hards" <chuckhards@yahoo.com> To: <utah-astronomy@mailman.xmission.com> Sent: Wednesday, January 29, 2003 1:29 PM Subject: Re: [Utah-astronomy] Eyepiece seminar
I'll start seeing what optics are available, and gathering materials. To keep costs down, we'll probably build a Plossl or true symmetrical. If I can find some inexpensive triplets, the ortho can be explored. I may be able to offer kits of both designs, wait and see.
These "kits" will cost me about $15 each; is everyone who wants to participate able to pony-up fifteen bucks? I will make no profit on this endeavor, but must cover costs.
Although we probably will NOT use wood for a housing, optically we will be building something similar to the "Homemade eyepieces" I described in S&T a couple of years ago (Feb. 00).
Let me know if there are any particular questions you would like the speaker(s) to address.
Thanks!
C.
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Thanks for the input, Bob. We'll address your questions, surely. For now, I can tell you that aperture is irrelevant. F-ratio is what determines applicability. Chuck --- Marilyn Smith <bob-marilyn@worldnet.att.net> wrote:
Chuck-
I'm interested in the proposed eyepiece seminar, and would gladly pony-up $15.
I would like to have your speakers address the applicability of different designs of eyepieces for different telescope designs, such as very long vs.very short focal lengths. Which eyepieces offer the most benefit for a 20" f4, or a 8" f6, or a 4" f15?
Bob Grant
----- Original Message ----- From: "Chuck Hards" <chuckhards@yahoo.com> To: <utah-astronomy@mailman.xmission.com> Sent: Wednesday, January 29, 2003 1:29 PM Subject: Re: [Utah-astronomy] Eyepiece seminar
I'll start seeing what optics are available, and gathering materials. To keep costs down, we'll probably build a Plossl or true symmetrical. If I
can
find some inexpensive triplets, the ortho can be explored. I may be able to offer kits of both designs, wait and see.
These "kits" will cost me about $15 each; is everyone who wants to participate able to pony-up fifteen bucks? I will make no profit on this endeavor, but must cover costs.
Although we probably will NOT use wood for a housing, optically we will be building something similar to the "Homemade eyepieces" I described in S&T a couple of years ago (Feb. 00).
Let me know if there are any particular questions you would like the speaker(s) to address.
Thanks!
C.
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also, maybe the pros and cons of an longer fl eyepice plus barlow, vs. shorter fl for same relative magnification. I must have missed the email - when is the eyepiece seminar??? Thanks, Jim --- Chuck Hards <chuckhards@yahoo.com> wrote:
Thanks for the input, Bob. We'll address your questions, surely.
For now, I can tell you that aperture is irrelevant. F-ratio is what determines applicability.
Chuck
--- Marilyn Smith <bob-marilyn@worldnet.att.net> wrote:
Chuck-
I'm interested in the proposed eyepiece seminar, and would gladly pony-up $15.
I would like to have your speakers address the applicability of different designs of eyepieces for different telescope designs, such as very long vs.very short focal lengths. Which eyepieces offer the most benefit for a 20" f4, or a 8" f6, or a 4" f15?
Bob Grant
----- Original Message ----- From: "Chuck Hards" <chuckhards@yahoo.com> To: <utah-astronomy@mailman.xmission.com> Sent: Wednesday, January 29, 2003 1:29 PM Subject: Re: [Utah-astronomy] Eyepiece seminar
I'll start seeing what optics are available, and gathering materials. To keep costs down, we'll probably build a Plossl or true symmetrical. If I
can
find some inexpensive triplets, the ortho can be explored. I may be able to offer kits of both designs, wait and see.
These "kits" will cost me about $15 each; is everyone who wants to participate able to pony-up fifteen bucks? I will make no profit on this endeavor, but must cover costs.
Although we probably will NOT use wood for a housing, optically we will be building something similar to the "Homemade eyepieces" I described in S&T a couple of years ago (Feb. 00).
Let me know if there are any particular questions you would like the speaker(s) to address.
Thanks!
C.
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Hi Jim: --- Jim Stitley <sitf2000@yahoo.com> wrote:
also, maybe the pros and cons of an longer fl eyepice plus barlow, vs. shorter fl for same relative magnification.
Barlow use: Pro: Long eye relief, generally easier to use Con: greater absorption (dimmer image if poorly coated) If the Barlow is of good quality, the image with will be no less-sharp than that without. In this case, personal prefference wins, IMO.
I must have missed the email - when is the eyepiece seminar???
TBD. Somtime this summer, after my workload eases a bit. Right now I'm doing 60+ hr. weeks, through April and maybe till June, if I live through it. ;) C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Thank you SO much Chuck for your reply and feedback. I just love the bino parrolle. mount I bought from you - wnat a treat to use, and very reasonable cost - you could easily get another $10. or more for it and still eb a bargain. Thanks again, Jim --- Chuck Hards <chuckhards@yahoo.com> wrote:
Hi Jim:
--- Jim Stitley <sitf2000@yahoo.com> wrote:
also, maybe the pros and cons of an longer fl eyepice plus barlow, vs. shorter fl for same relative magnification.
Barlow use: Pro: Long eye relief, generally easier to use Con: greater absorption (dimmer image if poorly coated)
If the Barlow is of good quality, the image with will be no less-sharp than that without.
In this case, personal prefference wins, IMO.
I must have missed the email - when is the eyepiece seminar???
TBD. Somtime this summer, after my workload eases a bit. Right now I'm doing 60+ hr. weeks, through April and maybe till June, if I live through it. ;)
C.
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Chuck, The kits sound like a terrific deal. BTW, I start a new job on Tuesday! Yahoo! One question I've had for a long time, and I'll likely show my ignorance of optics here. But I've been wondering why it is that when you get down to the high power 3 or 4 element eyepieces (e.g., orthos and ploessls) the diameter of the glass shrinks to a tiny hole and the eye relief shrinks down to the point where you almost have to put your eyeball right to the glass to see anything? Does the short focal length not allow for a bigger diameter with the same curvature of the glass required for the magnification? In other words, is it possible to make a 6mm ortho that fits in a 2-inch barrel that doesn't require the top lens element diameter to be smaller than a soda straw? I suspect the answer is probably too long and complex for posting on this list, but if there's a short answer, I'd like to hear it! At least I hope you will address questions like this, and what the remedies might be if any (aside from adding more optical elements, creating in effect a built-in barlow which is what I suspect the radian and nagler designs employ, right?). One of the things that Mr. Dobson said about binocular eyepieces were the superb eye relief most of them afforded. Anyway, sounds like you might need to start the seminar with a short course on optical physics! I for one sure wouldn't mind. Meanwhile, I'll have to go back and look up your S&T article. I never did read it that I can remember. Sorry to be so long winded. And please don't feel like you have to respond to all this rambling (a waste of your time). You can save it for your seminar this summer. -Rich --- Chuck Hards <chuckhards@yahoo.com> wrote:
I'll start seeing what optics are available, and gathering materials. To keep costs down, we'll probably build a Plossl or true symmetrical. If I can find some inexpensive triplets, the ortho can be explored. I may be able to offer kits of both designs, wait and see.
These "kits" will cost me about $15 each; is everyone who wants to participate able to pony-up fifteen bucks? I will make no profit on this endeavor, but must cover costs.
Although we probably will NOT use wood for a housing, optically we will be building something similar to the "Homemade eyepieces" I described in S&T a couple of years ago (Feb. 00).
Let me know if there are any particular questions you would like the speaker(s) to address.
Thanks!
C.
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Rich, take a look at this site; http://www.siebertoptics.com/ I'm not sure what type of lens' he uses that gives such a large eye lens but the FOV seems bigger, the eye relief seems to me to be a little better, but I haven't done any type of measuring to be able to tell you exactly how much more than versus a standard ortho or plossl of the same focal length. I'm sure that a call or email to him would answer some questions, as he's a very friendly guy! Howard PS, Chuck I'd cough up $15 bucks for a kit!! --- Richard Tenney <retenney@yahoo.com> wrote:
Chuck,
The kits sound like a terrific deal. BTW, I start a new job on Tuesday! Yahoo!
One question I've had for a long time, and I'll likely show my ignorance of optics here. But I've been wondering why it is that when you get down to the high power 3 or 4 element eyepieces (e.g., orthos and ploessls) the diameter of the glass shrinks to a tiny hole and the eye relief shrinks down to the point where you almost have to put your eyeball right to the glass to see anything? Does the short focal length not allow for a bigger diameter with the same curvature of the glass required for the magnification? In other words, is it possible to make a 6mm ortho that fits in a 2-inch barrel that doesn't require the top lens element diameter to be smaller than a soda straw? I suspect the answer is probably too long and complex for posting on this list, but if there's a short answer, I'd like to hear it! At least I hope you will address questions like this, and what the remedies might be if any (aside from adding more optical elements, creating in effect a built-in barlow which is what I suspect the radian and nagler designs employ, right?).
One of the things that Mr. Dobson said about binocular eyepieces were the superb eye relief most of them afforded.
Anyway, sounds like you might need to start the seminar with a short course on optical physics! I for one sure wouldn't mind.
Meanwhile, I'll have to go back and look up your S&T article. I never did read it that I can remember.
Sorry to be so long winded. And please don't feel like you have to respond to all this rambling (a waste of your time). You can save it for your seminar this summer.
-Rich
--- Chuck Hards <chuckhards@yahoo.com> wrote:
I'll start seeing what optics are available, and gathering materials. To keep costs down, we'll probably build a Plossl or true symmetrical. If I can find some inexpensive triplets, the ortho can be explored. I may be able to offer kits of both designs, wait and see.
These "kits" will cost me about $15 each; is everyone who wants to participate able to pony-up fifteen bucks? I will make no profit on this endeavor,
but
must cover costs.
Although we probably will NOT use wood for a housing, optically we will be building something similar to the "Homemade eyepieces" I described in S&T a couple of years ago (Feb. 00).
Let me know if there are any particular questions you would like the speaker(s) to address.
Thanks!
C.
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Hey Chuck, Count me in! -- Joe Joe Bauman science & military reporter Deseret News bau@desnews.com (801) 237-2169
I spoke with my friend in Ohio last night (the one who owns the Siebert eyepieces I mentioned yesterday). He told me that the Konig varaint that I wasn't too pleased with was actually made by Russell Optics. Chuck __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Chuck, What displeased you about the Russell Konig? Just Curious. Greg --- Chuck Hards <chuckhards@yahoo.com> wrote:
I spoke with my friend in Ohio last night (the one who owns the Siebert eyepieces I mentioned yesterday). He told me that the Konig varaint that I wasn't too pleased with was actually made by Russell Optics.
Chuck
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Greg: Still trying to deal with today's sad, sad news. As I recall, and bear in mind that it has been a couple of years, the eye-relief was shorter than I had expected, and there was more-than-usual amount of field curvature. It wasn't a bad eyepiece, but I thought it could have been better. I'm a Konig user myself, and the design is capable of more. C. --- Greg Taylor <astronomus_maximus@yahoo.com> wrote:
Chuck,
What displeased you about the Russell Konig? Just Curious.
Greg
--- Chuck Hards <chuckhards@yahoo.com> wrote:
I spoke with my friend in Ohio last night (the one who owns the Siebert eyepieces I mentioned yesterday).
He told me that the Konig varaint that I wasn't too pleased with was actually made by Russell Optics.
Chuck
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Armed with electronic & computer training 25 years out of date, I managed to get this thing running again without giving a techie any of my hard-earned money! I'm back on-line at home. Good luck on the shuttle expedition, please post your impressions when you get home! Chuck __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Chuck Your are righty in line with Bush's economic plan not helping out the techies. Remember his moto: "I will leave no millionaire behind." Jim Chuck Hards <chuckhards@yahoo.com> wrote:Armed with electronic & computer training 25 years out of date, I managed to get this thing running again without giving a techie any of my hard-earned money! I'm back on-line at home. Good luck on the shuttle expedition, please post your impressions when you get home! Chuck __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy --------------------------------- Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now
--- Jim Gibson <xajax99@yahoo.com> wrote:
Chuck Your are righty in line with Bush's economic plan not helping out the techies. Remember his moto: "I will leave no millionaire behind."
Ha! I hadn't thought of it that way. Necessity was the driving force (and being cheap by nature);) Only problem now is two off-color areas on the monitor. Can't seem to find a de-gauss on this thing, but a super-magnet helps a bit (carefully away from the computer!) C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Siebert's not doing anything that you can't do yourself. I've seen a few of his eyepieces, two were very good, one, a Konig variant, didn't fare so well. All were machined plastic (great minds think alike! ;) C. --- Howard Jackman <sumoetx@yahoo.com> wrote:
Rich, take a look at this site; http://www.siebertoptics.com/ I'm not sure what type of lens' he uses that gives such a large eye lens but the FOV seems bigger, the eye relief seems to me to be a little better, but I haven't done any type of measuring to be able to tell you exactly how much more than versus a standard ortho or plossl of the same focal length. I'm sure that a call or email to him would answer some questions, as he's a very friendly guy!
Howard
PS, Chuck I'd cough up $15 bucks for a kit!!
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Hi Rich: --- Richard Tenney <retenney@yahoo.com> wrote:
The kits sound like a terrific deal. BTW, I start a new job on Tuesday! Yahoo!
Hey, great news! Congratulations!
In other words, is it possible to make a 6mm ortho that fits in a 2-inch barrel that doesn't require the top lens element diameter to be smaller than a soda straw?
No. Lets assume that an eyepiece is just one fat lens for the purpose of argument (which is the way the eyepiece works in practice, anyway). Think f-ratio of the eyepiece lenses, not just focal length. If the eye lens were say, 20mm in diameter, the FOCAL RATIO of that lens would have to be about F/0.3 to achieve the desired FOCAL LENGTH. Lenses of F/0.3 do not form very good images! The "sweet spot" of diffraction-limited performance would be microscopic, if there was one at all, and the rest of the field would be horribly curved. Just like our telescope objectives, longer F-ratios mean better imagery. So, to get a larger distortion-free zone, we have to change that F-RATIO. To keep the focal length the same, you have to reduce diameter to increase the RATIO (like a camera lens iris). Get it? Short focal-length eyepieces with large eye lenses are in fact augmented with internal Barlows. In this case we are cheating by actually increasing the apparent focal length of the objective...remove the internal Barlow, and those eyepieces are really more like 20-25mm eyepieces. UO some years ago had a high-powered eyepiece line in 2" barrels, but they didn't sell. The larger barrel added to cost & weight while adding nothing to performance. Remember that with high-powered eyepieces, you are only looking at a tiny portion of the virtual image at prime focus....you don't need a 2" barrel. Most of a 1.25" barrel is wasted, for that matter. Long eye-relief and wide field can be mutually exclusive qualities, I'll demonstate this graphically at the seminar. Imagine looking through a 1" knot-hole in a wood fence. If your eye is right up against that hole, you can see quite a panorama on the other side....Now, back your head back from the hole a bit, and you can see how that panorama shrinks...a similar effect is taking place with eyepieces. In practice, a wide field can be obtained by making the "field lens" of larger diameter than the "eye lens" in any given eyepiece design, not too hard to do. Now you're looking through a funnel from the small end, instead of a tube of constant diameter. This is all pretty simplified, but we'll get a little meatier at the seminar.
One of the things that Mr. Dobson said about binocular eyepieces were the superb eye relief most of them afforded.
Some, yes, but the cheapies usually use 3-element Kellner variants with marginal eye-relief, but wide field. Remember the eye-relief/wide field tradeoff. I know the eyepieces on the Obies/Bears/Galileo 15x70mm binos are a great compromise...wide field and reasonable eye-relief.
Anyway, sounds like you might need to start the seminar with a short course on optical physics! I for one sure wouldn't mind.
Meanwhile, I'll have to go back and look up your S&T article. I never did read it that I can remember.
Shame! Shame! You're off my Christmas list! ;) I didn't write those for the money, you know! (well, OK, I did a little bit....) Chuck __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Chuck, Thank you! Excellent explanation, and yes, I finally get it -- perfect analogy with the camera's depth of field increase as the iris shrinks -- that IS something I'm familiar with. -Rich --- Chuck Hards <chuckhards@yahoo.com> wrote:
So, to get a larger distortion-free zone, we have to change that F-RATIO. To keep the focal length the same, you have to reduce diameter to increase the RATIO (like a camera lens iris).
Get it?
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Here's another thought related to Rich's question. Think of the eyepiece as a loupe or magnifying glass (since that's really exactly what it is). The objective forms an image at the focal plane, the eyepiece magnifies that image. If you've ever looked closely at loupes, then you've noticed that the higher the power, the smaller the diameter of the lenses, for the reason (F-ratio) already discussed. And what are considered to be the highest-quality loupes? Those using triplets, essetially an orthoscopic eyepiece! The single element in orthos is typically used to increase AFOV by shortening focal length. It's the triplet that does all the work! C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
I spent several hours over the weekend looking for lenses for the seminar eyepiece kits, and was disappointed in the selection I found. There are far fewer appropriate lenses in the surplus market today, than there were 3 years ago when I was heavily involved in eyepiece making. I did find some lenses good for symmetricals & Plossls, as well as a couple of triplets that might work for orthos, however prices have risen in the last few years. If it looks like lens prices alone will exceed fifteen dollars, I'm less inclined to make the effort. I would have to sell all of these kits to make it worthwhile, and once you get around $20-$25, there isn't much motivation to make your own eyepiece other than curiosity. Bill Kelley has contacted me regarding some nice little achromats that will work, if we can get enough of them. (Thanks, Bill!) My own parts bins have only enough lenses for perhaps four or five eyepieces right now. Stay tuned. C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Chuck, List, How about 100 of them? Bill
Bill Kelley has contacted me regarding some nice little achromats that will work, if we can get enough of them. (Thanks, Bill!)
My own parts bins have only enough lenses for perhaps four or five eyepieces right now.
Chuck, Sorry for the late input on the eyepiece seminar idea. I have been under the weather lately (long story). That and I am still in shock over the tragic events of the weekend. Reading all of your posts have certainly helped focus my thoughts this week. Patrick W. sure vocalized all of our thoughts that next day, thanks a bunch. Down to business... I have improved my Excel spreadsheet on eyepiece design. I would be more than willing to release it to the eyepiece seminar group for their free use. I would rather not release the version that I gave to you just because it is not as polished as I wanted it. I'll email you the "latest greatest" as soon as I tweak it a little more and include a text file to explain its use. Bye the way C.H., what happened to your webpage on eyepiece design? The old link doesn't work and a modest search for it only shows your wooden telescope making pages. That e.p. design page was great and to the point. Include me in on the fun. Tnx es 73 de n7zi Gary Liptrot Why buy something for ten bucks when you can make it for a hundred... J.R. -----Original Message----- From: utah-astronomy-admin@mailman.xmission.com [mailto:utah-astronomy-admin@mailman.xmission.com]On Behalf Of Chuck Hards Sent: Monday, February 03, 2003 10:07 AM To: utah-astronomy@mailman.xmission.com Subject: Re: [Utah-astronomy] Eyepiece seminar I spent several hours over the weekend looking for lenses for the seminar eyepiece kits, and was disappointed in the selection I found. There are far fewer appropriate lenses in the surplus market today, than there were 3 years ago when I was heavily involved in eyepiece making. I did find some lenses good for symmetricals & Plossls, as well as a couple of triplets that might work for orthos, however prices have risen in the last few years. If it looks like lens prices alone will exceed fifteen dollars, I'm less inclined to make the effort. I would have to sell all of these kits to make it worthwhile, and once you get around $20-$25, there isn't much motivation to make your own eyepiece other than curiosity. Bill Kelley has contacted me regarding some nice little achromats that will work, if we can get enough of them. (Thanks, Bill!) My own parts bins have only enough lenses for perhaps four or five eyepieces right now. Stay tuned. C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy
Hi Gary, good to hear from you again, hope you're on the mend. You wrote:
Down to business... I have improved my Excel spreadsheet on eyepiece design. I would be more than willing to release it to the eyepiece seminar group for their free use. I would rather not release the version that I gave to you just because it is not as polished as I wanted it. I'll email you the "latest greatest" as soon as I tweak it a little more and include a text file to explain its use.
I'd love to have it with the seminar material, thanks!
Bye the way C.H., what happened to your webpage on eyepiece design? The old link doesn't work and a modest search for it only shows your wooden telescope making pages. That e.p. design page was great and to the point.
I've never had my own Web-page. Everything I've ever had up was on other people's servers. I guess Roger Philips has other plans for his site. One of these days, I plan to put up my own site, divided into two halves. One side will reflect my ATM work, the other will be devoted to WW1 aircraft & pilots. C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
The tragedy over the weekend reminded me that Frank Moss passed away recently. Senator Moss tried very hard to get a shuttle landing facility built in the west desert, only to lose-out to Edwards, IIRC. When I was a senior in high-school, in 1977, Senator Moss brought the entire crew of Apollo-Soyuz to Utah. They spoke at an assembly at my school, after which I presented the Soviet commander with a model of the two spacecraft linked together...I wonder if he still has it? I sketched a pen-and-ink drawing of the mission patch, and had all five crew members autograph it. I still have it today, even though I believe that 2 of the crew members have since passed-on. One of the newspapers did a small story on my presentation to Leonov, I still have a clipping. The most fortuitous part was that I filmed 4 or 5 minutes of the assembly on 8mm film, which I still have. I'd like to convert it to a digital file one of these days. Even earlier, when I was in grade school, I remember that the Apollo-11 capsule was displayed on Capitol Hill in a large touring trailer. I think I was in seventh or eighth grade, but went prepared....I had a roll of scotch tape in my pocket. Stood quietly in line, waiting my turn to view the capsule. When it came, I noted when the armed guard (!) turned away, and quickly slapped a piece of tape on the capsule. Pulling it back, I saw that some of the capsule patina had come off on my tape. I had a piece of Apollo-11! Then the guard turned back, saw what I was doing, and chased me off! Probably my most proud NASA story is that I was born on the day the agency was signed into existence (actually NACA, it's predecessor): Oct. 1, 1958. There are good memories associated with the space-program. We need to hold onto those. C. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
BTW, Deb, you probably already know that Dawe's limit is for equal brightnes 6th magnitude stars.Brighter stars like zeta Bootis, 52 Orionis, beta Delphini, Lambda Ophiuchi, and 32 Orionis are more difficult than Dawe's limit suggests. Brent --- UTAHDEB@aol.com wrote:
Has anybody had success splitting these doubles?:
Lambda Oph 52 Orionis 32 Orionis 36 Andromedae Zeta Bootis Lambda Cygni
If so let me know the magnification and aperature.
Thanks,
Debbie
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I'm glad you added that caveat, Brent! With unequal brightness, sometimes the companion is swamped in the glare of the primary, even though it should be an easy split, by the numbers. Good advice. C. --- Brent Watson <brentjwatson@yahoo.com> wrote:
BTW, Deb, you probably already know that Dawe's limit is for equal brightnes 6th magnitude stars.Brighter stars like zeta Bootis, 52 Orionis, beta Delphini, Lambda Ophiuchi, and 32 Orionis are more difficult than Dawe's limit suggests.
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participants (12)
-
Bill Kelley -
Brent Watson -
Chuck Hards -
Gary Liptrot -
Greg Taylor -
Howard Jackman -
Jim Gibson -
Jim Stitley -
Joe Bauman -
Marilyn Smith -
Richard Tenney -
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