hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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The star test is the ultimate method for the collimation and quality verification of your telescopes. Sadly, a real star is not always available, and you really may not want to spend your precious observation time doing collimation and verification even when it is available. Of course, you will also need a good tracking system for doing star test with the moving real star. After all the troubles, due to the turbulence, the real star may not even reveal the true quality of your telescopes.
An artificial star will provide you an excellent alternative mean to do the star test anytime and anywhere you want, without all the drawbacks of the real stars. However, the problem with artificial star is that you really need different size of artificial stars for different telescopes of different apertures with different F/#, and even for the same telescopes but at different distances, and under different lighting environment.
Our five-star artificial star is a perfect solution to this problem. It has 6 bright white LEDs with 5 precision pinholes (50/100/150/200/250 microns). It will enable you to test practically all the telescopes of different apertures with different F/#, from any reasonable distances needed!
-You can instantly find out which star is best for your particular telescope at that particular distance under that particular lighting environment.
-You can adjust the brightness of the stars by twisting the LED head.
-You can mask out any 4 stars with a provided magnetic mask.
Please make sure the cleanness of the mask, and use it only when needed to prevent the blockage of the pinholes.
To purchase a 5-star Artificial Star at $14.95:
http://hubbleoptics.com/artificial-stars.html
or
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=200331472146
Thank you,
Tong
Hubble Optics
Edited by hubble-optics (04/15/09 09:40 PM)
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skyjim
professor emeritus
Reged: 01/13/07
Posts: 589
Loc: Long Island, NY
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Hi Tong, will you be at Neaf this weekend maybe??? If not I dont use ebay, do you have a sight or phone # I can contact your company at?
Jim
--------------------
Skywatcher 120ED Pro,Skywatcher 8"SCT
Skywatcher 10" Truss Tube Dob
Astro-Tech AT80FD w/WO/TMB co-designed Fluorite Doublet,Orion Sirius EQ,CG5 EQ mounts
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Daniel Mounsey
Vendor - Woodland Hils
Reged: 06/12/02
Posts: 3200
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Sounds like a good price too.
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Posts: 25187
Loc: NE Ohio
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Quote:
Sounds like a good price too.
Yup. For $20 I'll give it a shot (should be better than the Christmas tree ornament I spent a few hours staring at last weekend at 600X). 
--------------------
John C
Urban Observatory
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 178ED F/9 "APO"
Meade ETX-125AT
C14
Teeter 20" F/3.8 truss Newt w/ServoCat
CI-700, NJP, GPDX/SS2KPC, CG5-GT
ST-10XME, DSI Pro
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Hi Jim,
I am sorry that we will not be in NEAF. However, we have just added a page in our website where you can order it directly:
http://hubbleoptics.com/artificial-stars.html
You can contact us at info@hubble-optics.com
Thank you and best regards,
Tong
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snowdragonusa
Pooh-Bah
Reged: 09/04/07
Posts: 1128
Loc: Denver, CO
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Yup, me too. I just ordered one. For $20 shipped I'll give it a go. Our Colorado skies make it difficult to get a good collimation most evenings.
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Adam
12" LX200R, AT80LE
Lunt 60mm Ha & CaK solar scopes
DMK41.AS, DSI Pro, DSI-C, LPI
Denver Astronomical Society
Brighton Astronomical Group
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Thank you all for the support. BTW, we have just added a note in our website to indicate the products will be shipped in about week. Sorry for the late notice and the waiting time.
Tong
Hubble Optics
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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I just pulled the trigger on this gizmo. I've always heard that to properly collimate your optics or to test your optics, you should do a star test. The catch-22 is that to do a proper star test you need close-to-perfect seeing. Yeah, like that's going to happen on a regular basis where I live. So now we'll see if I have a long enough run in my house to perform the test. I guess I could rig up a system of mirrors to fold-up the rays. Why not? We do it all the time in our Newts and Cats and Binos.
Mike
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Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Tong's website brought up another positive point about using an artificial star for collimating. If you use a real star, you really need to track it. Otherwise you'll be pulling your hair out glancing at the out-of-focus star at high power, jumping back to adjust the screws on back of the mirror, nudging the star back into view, jumping back to the screws, nudging the star back ... Not something I would want to do. I suppose you could teach a friend or your wife how to adjust collimation screws or interpret an airy disk. Also, something I may not want to do. Forgetaboutit. Some things are better done alone.
An idea: If you set up the artificial star in your house right beside your scope, and point them both at a mirror at the farthest distance away at the other end of your house, you would be able to set it up in half the distance and could just reach over to select a different size pinhole or adjust the brightness as needed. It may even be possible to insert the artificial star in your optical or laser finder mount attached to your scope tube, or via a 1/4-20 screw to your scope's ring, and adjust its position easier from there.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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jsiska
super member
Reged: 07/12/06
Posts: 193
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Interesing. Can you provide a little more detail on how to determine which of the 5 precision pinholes (50/100/150/200/250 microns) are to be selected based on the telescopes of different apertures with different F/#, and also with usage of different reasonable distances.
Thanks,
Jim
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Jim,
I'm at a loss as to those details, myself. This sounds like a good question for Mr. Tong.
Mike
For Mr. Tong,
We'd appreciate a little help in this regard, Mr. Tong.
Thanks,
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Dick Suiter’s Star Testing Astronomical Telescope has a full explanation on this topic, in particular, the section 5.2.1, Distance of Artificial Sources and 5.2.2, Diameter of Artificial Sources.
Here is a direct quote from page 86:
“We must carefully select a pinhole size in the artificial source so that it is smaller than the resolution of the instrument. On the other hand, it must be large enough to allow sufficient illumination to fill a defocused image with light. To calculate such a diameter, we extend the Airy disk radius to the distance of the pinhole”
Table 5-2 gives out the min telescope to artificial star distance, and Table 5-3 gives out the max diameter of artificial stars for different telescope (Apertures, F/#).
As for the 5-star artificial star, the rule to choose the best star is very simple; for whatever scope at whatever distance, you should always choose the smallest possible star, but which still give you the clear defocus image.
Best regards,
Tong
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snowdragonusa
Pooh-Bah
Reged: 09/04/07
Posts: 1128
Loc: Denver, CO
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Quote:
An idea: If you set up the artificial star in your house right beside your scope, and point them both at a mirror at the farthest distance away at the other end of your house, you would be able to set it up in half the distance and could just reach over to select a different size pinhole or adjust the brightness as needed. It may even be possible to insert the artificial star in your optical or laser finder mount attached to your scope tube, or via a 1/4-20 screw to your scope's ring, and adjust its position easier from there.
Hmmm, an interesting idea. However, wouldn't you be be collimating any surface errors of the mirror? Similar to collimating with or without your diagonal?
--------------------
Adam
12" LX200R, AT80LE
Lunt 60mm Ha & CaK solar scopes
DMK41.AS, DSI Pro, DSI-C, LPI
Denver Astronomical Society
Brighton Astronomical Group
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Tong,
"Dick Suiter’s Star Testing Astronomical Telescope"
Oh yes, I'd like to own a copy of this guide and be able to consult it at my leisure, but with it being apparently out of print, and used copies selling for $127, I think for the immediate future I'll be limited to little snippets such as you have given graciously here.  
"To calculate such a diameter, we extend the Airy disk radius to the distance of the pinhole”
Whoa! English is my native language and a know something about astronomy and optics, but ... huh?
"As for the 5-star artificial star, the rule to choose the best star is very simple; for whatever scope at whatever distance, you should always choose the smallest possible star, but which still give you the clear defocus image."
I like your precedure better, Tong. Much simpler and easier to understand. 
Thanks for the help,
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Adam,
"Hmmm, an interesting idea. However, wouldn't you be be collimating any surface errors of the mirror? Similar to collimating with or without your diagonal?"
Hey, I'm new to any kind of collimating beyond peephole caps, cheshires, sight tubes and laser collimaters. (And I've stopped using the lasers. They give a false sense of perfection, as I see it.) I am still trying to figure all this out. I've never done a "star test." (Why waste a rare night of good seeing on collimating? I want to observe stuff.) I collimate with the diagonal. How and why would you do it any other way?
Seriously though, I might be wrong, but I think that surface errors of a flat mirror wouldn't really affect the collimation. Maybe I'll use an old diagonal that's about 25 years old and is up in the attic. I could mount it on a tripod. Hey, unless I do something to fold the light path, I might not have enough room in my house to do the test! I don't have a back yard I can utilize for such things. And I don't want to wait until I'm out in the field to do the artificial star collimation, though I guess that is possible if I travel to a dark site.
Mike
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Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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The HRS's must have Star Testing Astronomical Telescopes, Second Edition, is ready to ship now! Better yet, it is still priced at special pre-publication offer at $29.95, at least for now!
http://www.willbell.com/TM/tm5.htm
Thanks,
Tong
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Hi Tong,
Thank you much for the heads up about the Star Testing book. Yes, ordering it pre-publication is probably the only way to get it at a reasonable price. I'm still awaiting the next publication announcement for Rukl's Atlas of the Moon.
Thanks,
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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I just ordered Star Testing Astronomical Telescopes, Second Edition from willbell.com. I also picked up a copy of Bright Star Atlas so I can take it out with my binos and grab-n-go scopes.
Thanks again, Tong!
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Mike,
You are welcome! BTW, here are some very useful online helps on star test:
http://perso.club-internet.fr/legault/collim.html
http://www.astunit.com/tutorials/startest.htm
Some very helpful star test examples, and an extremely useful star test simulator to get familiar with star test
http://aberrator.astronomy.net
Best regards,
Tong
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Tong,
I'll check them out. I've used telescopes since the early '70's, but I'm still a newbie when it comes to star testing, so I need all the help I can get.
Thanks,
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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raf1
super member
Reged: 11/18/05
Posts: 145
Loc: Texas
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Greetings Tong,
While I have already placed my order for the artificial star, I was wondering ..... would the artificial star(s) allow one to check autofocus routines via FocusMax, MaxImDL, etc? Being able to run these routines indoors in a controlled environment would really be an added benefit in addition to collimation.
Just curious.
--------------------
-Ron
****************************
Too much "stuff" and too little time to use it .....
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Hi Ron,
Thank you for your support! We have not tried it yet, but I am very sure it should work; but of course you do need to put the star(s) far enough to bring the focus within the travel of the focuser.
BTW, you should be able to use a wonderful free software, MetaGuide by Frank Freestar8n (http://www.astrogeeks.com/Bliss/MetaGuide/index.html), to collimate your scope precisely (quantitively!) with the artificial star and a web-cam.
Best regards
Tong
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jim_m
member
Reged: 10/25/08
Posts: 51
Loc: Virginia, USA
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Hi Tong,
You just sold another one, really need this to save the little "good seeing time" for seeing.You are just up the road from me ny about 50 miles, so you can probably understand my mess.
Looking forward to delivery.
Jim
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Hi Jim,
Thank you for your support. The products will be shipped from HK via HKPS air service on April 22, 2009. It will have a more suitable black finishing, very sleek.
BTW, I am in HK right now, much less and worse seeing than VA
Best regards,
Tong
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Trever
Carpal Tunnel
Reged: 08/18/03
Posts: 2978
Loc: North Alabama
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I ordered one also and am excited to try it out!
--------------------
Trever
Explore Scientific 152mm F/6.5 Achromat
Celestron CGEM 11 XLT SCT
Lunt LS60THaDS50 B1200 w/pressure tuner
Nikon 8x42 Trailblazer Binos
Stellarvue M1 mount
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Trever,
Thank you for your support. We are on schedule to ship most (if not all) outstanding orders tomorrow. Please note that 3 AAA batteries needed are NOT included.
Best regards,
Tong
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Strgazr27
Vendor - Deep Space Mods and Composites
Reged: 10/04/04
Posts: 6984
Loc: StonyHill Observatory
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Tong,
Picked mine up yesterday off Ebay. Looks real nice and can't wait to see it in action. Hoping it helps make collimating my RC a bit easier.
CS's
--------------------
Bobby
StonyHill Observatory
Skywatcher EQ6 Pro (On it's way)
AT 130 F/6 Prototype
Royce 10" f/4 Astrograph (Under Construction)
Self Modded 40D
70-200 F2.8 L IS
SSAG
YAHOO TMB 130SS Group
Astronomy Technologies Yahoo Group
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Bobby,
Thank you very much and hope it will be indeed a very helpful tool to you! BTW, your order, actually all outstanding orders have been shipped out today! Your feedback will be much appreciated.
Best regards,
Tong
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Tong,
I went ahead and took a pre-publication order for Dick Suiter’s Star Testing Astronomical Telescopes from willbell.com at a discount. I received it yesterday! It's a treasure trove of information on star testing and the various abberations. This will be highly educational for me. At first glance, many of the star images look pretty much the same. It will take a while to recognize the subtle differences. Thanks for telling me about willbell.com. I highly recommend them. Now I'll be able to put your artificial star to good use when it arrives.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Hi Mike,
Great to know you got the book already, the star is on the way. I have found running aberrator while reading the book is very rewarding.
Best regards,
Tong
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Hi Tong,
Yes, the program looks very impressive. I'll have to download it and check it out. I think we have a little computer camera around here somewhere that my son used to play interactive games over the internet. I have no experience with that gizmo. (Or texting or internet-on-a-phone.) Is it what would be needed to use the program?
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Mike,
Actually you don’t need a web-cam to use this program. The aberrator is a star test simulator, you input your scope parameters(Aperture, Obstructgion ratio, Focal Ratio), the defocus, and the possible aberrations, then the aberrator will generate the corresponding star test images. You can then compare the genetared images with what you see in the real star test to get a very good idea about the quality of your scope. Of course, it will be better if you can use the web-cam to capture your star test images and compare with the generated images side by side. You do need a web-cam with 1.25” adapter, such as Philips SPC1290NC, otherwise you will need a separated web-cam/1.25” adapter (http://www.scopetronics.com/webcam.htm).
Somehow the aberrator’s web site is down (http://aberrator.astronomy.net) now, but you can download it from our web site for the time being (http://www.hubbleoptics.com/files/aberrator30.exe)
Hope this help,
Tong
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Tong,
Thanks again for the help. Maybe the interest that you have generated in the program has overloaded the web site.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Hi Mike,
I have no problem if our site gets overloaded(  ).
Anyway, the fun continues (But I am afraid this thread will be moved to DIY forum...). You can even try out your FREE 3M Bahtinov focusing mask with it if you want:
(1) Go to http://astrojargon.net/MaskGen.aspx to generate a mask for your scope.
(2) Use Mozilla Firefox to print it on a 3M transparency film; make sure to use the right kind of film for your printer (InJet, or LaserJet) and print it on the right side! That's it, a Lightweight 3M Bahtinov focusing mask.
(3) Now, try it out with the Hubble 5-star! You need use the brightest star now.
Best regards,
Tong
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SilentLight
member
Reged: 11/29/08
Posts: 83
Loc: Los Angeles, CA
|
|
Tong,
Can you possibly import some of your artificial stars to US and ship domestically? I quite often have trouble with international deliveries. Normally caused by our mail carrier. 
Thanks...
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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|
Thank you for the suggestion. Although we wouldn’t be able to do it on our own, but one (and maybe more) of the well-known Astro Products dealers has stepped in to help. The products are already on the way to their store, and they will make an announcement later. BTW, they are in LA area, not far from you...
Best regards,
Tong
|
LDb
professor emeritus
Reged: 02/01/08
Posts: 533
Loc: Cleveland, Ohio
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|
Hi All,
I ordered one -- for the $20.oo I'll give it a try -- looks like a clever tool and concept and you can't beat the price because the precision pinholes I use in my lab each cost more than the whole artificial star from Hubble.
We'll see how it goes.
Clear skies all,
Howard
--------------------
10" LX200R-UHTC (on ScopeBuggy which is terrific)
ETX-90-RA
ATM'ed-8"f/8 and 4.25"f/10 planetary Newtonians
Brandon eyepieces: 48mm,32mm,24mm,7/8",12mm,16mm,8mm,6mm,4mm (yes-4mm; special build in 1985 from 1960 optics)
Double set for binoviewing
Dakin 2.4x Barlow
Vintage ep's:
Gailand 7mm WF, 16.3mm (THE Galoc), Bertele 18mm
Siebert Optics:
Black Knight BinoViewer, 0.6x-1x-2x Power Wheel, 4x-8x telecentric zoom barlow
Astro-Tech Titan WF ep's: 38mm, 32mm, 26mm, 20mm, 15mm, 10mm
|
Manish
Vendor (AGENA AstroProducts)
Reged: 02/22/05
Posts: 115
Loc: Los Angeles Area, CA
|
|
Hi everyone,
We are pleased to announce that we are now an official distributor of Hubble Optics' 5-Star Artificial Star. We have this item in stock, ready to ship from our office in the Los Angeles area. Our price includes USPS first class shipping in the US.
You can view/purchase this item from the following link:
Hubble Optics 5-Star Artificial Star
Thanks,
Manish
Agena AstroProducts
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Tamiji Homma
Pooh-Bah
Reged: 02/24/07
Posts: 1084
Loc: California, USA
|
|
Hi Tong,
I received 5-star Artificial Star today. I just tried it inside house with two refractors (102mm f/8 and 80mm f/7.5)
The smallest star works perfectly inside house (about 40 feet). Star test can be done inside house
Thank you for functional and affordable product.
Tammy
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Tammy,
Thank you for your feedback. It is great to know the 5-star works out for you!
Best regards,
Tong
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Hi Manish,
Thank you for your help! Let your star shine...
Best regards,
Tong
|
Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
|
|
Tammy,
Quote:
The smallest star works perfectly inside house (about 40 feet). Star test can be done inside house
That's good to know. I live in a two-level condo, no backyard, and need to be able to do the test inside my house.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
Tamiji Homma
Pooh-Bah
Reged: 02/24/07
Posts: 1084
Loc: California, USA
|
|
Quote:
Tammy,
Quote:
The smallest star works perfectly inside house (about 40 feet). Star test can be done inside house
That's good to know. I live in a two-level condo, no backyard, and need to be able to do the test inside my house.
Mike
Hi Mike,
There are a few gotchas though. One is to able to focus that short distance (need plenty backfocus, extension tube), and the size of star isn't quite small to be point of light with the short distance.
Having said that, it is excellent alternative. I don't have to wait for perfect seeing night I even can do star test on rainy day inside.
I think it is perfect for collimation. I'll try it with Vixen VMC260L this weekend. I may need to do it outside to get enough distance. I have only about 60 feet straight line inside house.
Tammy
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
|
|
Hi Tammy,
Quote:
One is to able to focus that short distance (need plenty backfocus, extension tube)
I knew that set of focus tube extensions that I bought would come in handy one day!
Quote:
I don't have to wait for perfect seeing night I even can do star test on rainy day inside.
Yes. If it were ever perfect seeing outside, I want to be looking at planets, not doing a star test.
Quote:
I may need to do it outside to get enough distance. I have only about 60 feet straight line inside house.
My mom lives in the court behind us, so I suppose I could arrange with her to set up the artificial star in her garage or on top of her car, while I look at it through a telescope from our window. It would be much more convenient, though, to do the entire test within the confines of my own house anytime of the day or night. I still like the idea of using a mirror to fold the light beams and halve the actual distance needed.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
Greg K.
Reged: 12/11/03
Posts: 11505
Loc: Clifton Park, NY
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Just ordered one of these. At this price it sure beats making one myself.
--------------------
Astro-Tech AT111EDT f/7 - Celestron CGEM
NexStar 11 GPS
Orion SkyView Pro 8EQ (w/ Autostar mod)
15x70 Celestron SkyMasters
Orion 90mm Mak
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Hi Mike,
Your mirror folding star test is a wonderful idea! I have just tried it, it works GREAT! But I am using a mirror quite flat (It is a flat, I admit), but you will be surprised to find out how flat your dressing mirror can be!
Best,
Tong
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
|
|
Hi Tong,
I'm happy to hear that it works. Using a mirror to decrease the required distance will make collimation a lot easier for me. Not everybody has a long basement or backyard they can set up in. I have a couple extra diagonal mirrors that I could choose from for the purpose. They are both about 35 years old, though, so I don't know how bright they will be. I suppose I could buy an inexpensive optical flat somewhere. Maybe I could even attach the flat or a diagonal to a 1/4-20 adapter and mount the mirror on a tripod. Then I'll set the scope and the artificial star side-by-side, both aimed at the mirror, thereby halving the distance required for collimation. If the collimation requires 80', then my setup would only need 40'. An array of two mirrors might be put together to require only 20'. It would be a snap to adust the mirror on the tripod. You would only need to reach right beside you to adjust the artificial star.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Hi All,
Some customers have reported the units can not be turned on. Please make sure all batteries are in good contact at both ends. Twist the batteries a bit if necessary, and make sure it can be turned on before put the battery cage back into the tube.
Best,
Tong
Edited by hubble-optics (04/30/09 10:32 AM)
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
|
|
Tong,
My artificial star arrived yesterday in good shape. I inserted the AAA batteries. Everything works fine. It may be a while before I can actually set it up and test it out. I'll have plenty of time to work on it, though, because of the rainy weather lately and the waxing moon. But I plan on seeing if I can attach it to my 10" Newt using a finder mount. That way it would be easier to adjust to line up with the flat mirror, and I could just reach over to select a different brightness. Also, I need to find a flat/diagonal and attach it to a tripod. This plan seems to me the best way to use the artificial star, at least for me.
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
Trever
Carpal Tunnel
Reged: 08/18/03
Posts: 2978
Loc: North Alabama
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Hopefully mine will be here in the next couple of days. Too many clouds here so I have a great opportunity to collimate.
--------------------
Trever
Explore Scientific 152mm F/6.5 Achromat
Celestron CGEM 11 XLT SCT
Lunt LS60THaDS50 B1200 w/pressure tuner
Nikon 8x42 Trailblazer Binos
Stellarvue M1 mount
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SilentLight
member
Reged: 11/29/08
Posts: 83
Loc: Los Angeles, CA
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Received mine. Thanks Manish for super quick shipment
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Mike,
Thank you for the good news. I am looking forward to hearing the feedback on your folding star test.
BTW, another possiblity is to use the 5-star with the CCDInspector (http://www.ccdware.com/downloads/) in Single Star Collimation mode, http://pk.darkhorizons.org/CCDI/1StarCollimation.htm I have not tried it myself, but sounds very interesting.
Tong
Edited by hubble-optics (05/02/09 07:53 PM)
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Trever
Carpal Tunnel
Reged: 08/18/03
Posts: 2978
Loc: North Alabama
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Mine came in also. Works great. Thanks again!
--------------------
Trever
Explore Scientific 152mm F/6.5 Achromat
Celestron CGEM 11 XLT SCT
Lunt LS60THaDS50 B1200 w/pressure tuner
Nikon 8x42 Trailblazer Binos
Stellarvue M1 mount
|
Trever
Carpal Tunnel
Reged: 08/18/03
Posts: 2978
Loc: North Alabama
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Quote:
Mike,
Thank you for the good news. I am looking forward to hearing the feedback on your folding star test.
BTW, another possiblity is to use the 5-star with the CCDInspector (http://www.ccdware.com/downloads/) in Single Star Collimation mode, http://pk.darkhorizons.org/CCDI/1StarCollimation.htm. I have not tried it myself, but sounds very interesting.
Tong
The link doesn't work until you take the period off of the end of the address.
--------------------
Trever
Explore Scientific 152mm F/6.5 Achromat
Celestron CGEM 11 XLT SCT
Lunt LS60THaDS50 B1200 w/pressure tuner
Nikon 8x42 Trailblazer Binos
Stellarvue M1 mount
|
netwolf
member
Reged: 09/03/05
Posts: 91
Loc: NSW, Australia
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Did you guys recive an email from Huble about a pottential overheating issue? They have provided a DIY fix guide. To blacken the inside of the mask so it does not reflect light back in. And to cut the spaces between the led holes in the reflector to provide better ventalation.
For those that have not seen it yet here is a link to there proposed fix.
http://hubbleoptics.com/files/5-StarOverheatingRepairment05-05-2009.pdf
Edited by netwolf (05/02/09 01:32 PM)
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zjc26138
Postmaster
Reged: 02/24/05
Posts: 5246
Loc: Mingo Junction, Ohio and Morga...
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I really should pick one these up.
--------------------
Custom AR5
Stellarvue 80/9D
Bosma Goto Mount
Clear, dark skies everywhere,
-Zachary
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Greg K.
Reged: 12/11/03
Posts: 11505
Loc: Clifton Park, NY
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netwolf, I ordered from Agena and received those instructions as well.
--------------------
Astro-Tech AT111EDT f/7 - Celestron CGEM
NexStar 11 GPS
Orion SkyView Pro 8EQ (w/ Autostar mod)
15x70 Celestron SkyMasters
Orion 90mm Mak
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Trever
Carpal Tunnel
Reged: 08/18/03
Posts: 2978
Loc: North Alabama
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Did the overheat repair. You definitely do NOT want to get ink on the holes. I had a very hard time getting it out of one of them. I had to use a very small drop of alcohol and compressed air to gently blow it out.
--------------------
Trever
Explore Scientific 152mm F/6.5 Achromat
Celestron CGEM 11 XLT SCT
Lunt LS60THaDS50 B1200 w/pressure tuner
Nikon 8x42 Trailblazer Binos
Stellarvue M1 mount
|
BSJ
member
Reged: 12/22/08
Posts: 98
Loc: Grand Isle, VT
|
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I found it easier to blacken the disc before removing it from the light. That way you have the whole thing to hold on to.
I touched up the edge before flipping it around for reinstallation.
--------------------
Brian S. Johnson
________________
Zhumell Z10D, Orion ST80, 114mm Meade Telestar (Re-hab'd)
8-24mm Hyperion Zoom
8mm, 17mm, 21mm Baader Hyperion 14mm & 28mm Fine Tune Rings
OPT OIII, Baader Fringe killer, Baader Moon & Sky Glow
Nikon 10x50 Action Extreme
StarDust Observing Chair
Astro-Tech Voyager Mount
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Trever,
Thank you very much for your tips, I also fixed the link. We did expect 5-star to be a hot product, but really not this HOT... 
We apologize for the problem and inconvenience caused! Please rest assured that we will work with all of you to have this issue taken care of to your complete satisfaction.
Best regards,
Tong
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Hi Brian,
Thank you so much for your early, and the first report, which has enabled the development of the quick fix to avoid further damage to other customers and keep this product to be a hot product, but not too HOT.
Best regards,
Tong
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Statement by Hubble Optics
Released on 05/07/2009
Certain amount of heat will be generated and trapped in the LED chamber by the super bright LEDs in the 5-star unit once it is turned on, which will eventually lead to an overheating problem. We have developed a procedure to fix this problem and have sent it out to all affected customers. However, we have realized that it is not convenient for our customers to perform this procedure. Therefore, we will send out new units to all our customers who have purchased our 5-star Artificial Star(s) with this problem, free of charge. The new unit has been thoroughly tested to have this problem completely eliminated. You do not need to return the old units; however, please do not use the old unit if you have not repaired it based on the instruction we have given via emails.
We are grateful to all our customers; and we appreciate your feedback, suggestion, and critics. We apologize to you for this problem and the inconvenience caused. There is no excuse for this problem; we should have done a much better job. Please rest assured that we will have this issue taken care of to your complete satisfaction.
Tong Liu,
Hubble Optics
info@hubble-optics.com
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Dear 5-star customers,
All replacement units have been sent out already. You should be able to receive it in about a week.
Thank you,
Tong
Edited by hubble-optics (05/12/09 07:41 PM)
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snowdragonusa
Pooh-Bah
Reged: 09/04/07
Posts: 1128
Loc: Denver, CO
|
|
Thanks Tong!
--------------------
Adam
12" LX200R, AT80LE
Lunt 60mm Ha & CaK solar scopes
DMK41.AS, DSI Pro, DSI-C, LPI
Denver Astronomical Society
Brighton Astronomical Group
|
SilentLight
member
Reged: 11/29/08
Posts: 83
Loc: Los Angeles, CA
|
|
Comes to think of it, one can use this gizmo to test the autoguider or fiddle with the guiding program in the comfort of the home, too. What is needed is something to slowly move the flashlight around.
Food for thoughts... 
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
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Very interesting idea! I am wondering what will happen if you just move the star slowly by hand, will the autoguider/mount follow? Surely you wouldn't move the real star this way, but...
Best, Tong
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BSJ
member
Reged: 12/22/08
Posts: 98
Loc: Grand Isle, VT
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What about putting it on a GEM?
On a stalk of some sort to enlarge the apparent motion.
--------------------
Brian S. Johnson
________________
Zhumell Z10D, Orion ST80, 114mm Meade Telestar (Re-hab'd)
8-24mm Hyperion Zoom
8mm, 17mm, 21mm Baader Hyperion 14mm & 28mm Fine Tune Rings
OPT OIII, Baader Fringe killer, Baader Moon & Sky Glow
Nikon 10x50 Action Extreme
StarDust Observing Chair
Astro-Tech Voyager Mount
|
SilentLight
member
Reged: 11/29/08
Posts: 83
Loc: Los Angeles, CA
|
|
Quote:
Very interesting idea! I am wondering what will happen if you just move the star slowly by hand, will the autoguider/mount follow? Surely you wouldn't move the real star this way, but...
Best, Tong
Since my computer is tethered to my mount using a short cord, I will be needing a very long hand 
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Posts: 25187
Loc: NE Ohio
|
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Quote:
Very interesting idea! I am wondering what will happen if you just move the star slowly by hand, will the autoguider/mount follow? Surely you wouldn't move the real star this way, but...
Best, Tong
You can achieve the same effect more easily by nudging the telescope and observing the autoguiding as it recenters the artificial star.
--------------------
John C
Urban Observatory
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 178ED F/9 "APO"
Meade ETX-125AT
C14
Teeter 20" F/3.8 truss Newt w/ServoCat
CI-700, NJP, GPDX/SS2KPC, CG5-GT
ST-10XME, DSI Pro
|
BSJ
member
Reged: 12/22/08
Posts: 98
Loc: Grand Isle, VT
|
|
I got my second unit today.
Thank you very much Tong! Works like a charm.
--------------------
Brian S. Johnson
________________
Zhumell Z10D, Orion ST80, 114mm Meade Telestar (Re-hab'd)
8-24mm Hyperion Zoom
8mm, 17mm, 21mm Baader Hyperion 14mm & 28mm Fine Tune Rings
OPT OIII, Baader Fringe killer, Baader Moon & Sky Glow
Nikon 10x50 Action Extreme
StarDust Observing Chair
Astro-Tech Voyager Mount
|
snowdragonusa
Pooh-Bah
Reged: 09/04/07
Posts: 1128
Loc: Denver, CO
|
|
Ditto! Thank you so much for taking the time to not only do the upgrades but for doing it all at no extra charge.
You run a very honorable business Tong. Many thanks.
Cheers!
--------------------
Adam
12" LX200R, AT80LE
Lunt 60mm Ha & CaK solar scopes
DMK41.AS, DSI Pro, DSI-C, LPI
Denver Astronomical Society
Brighton Astronomical Group
|
KevinUK
Vendor (DSLR-AstroMod)
Reged: 08/22/07
Posts: 720
Loc: N 51'53 W 00'25
|
|
Hi thank you for the item was received yesterday after 1 week. I tried to do some preliminary tests but could only manage to place it 10m or so from my scope a C9.25 2350mm F/10 due to space contraints. I could not attain focus using a 10mm ep only a 20mm??
How do I calculate how far away I have to put the torch from scope to be able to attain focus at the eyepiece?
Is there a formula for type of scope, focal length, focal ratio, ep??
Thanks!
|
Manish
Vendor (AGENA AstroProducts)
Reged: 02/22/05
Posts: 115
Loc: Los Angeles Area, CA
|
|
Dear all,
We just received our shipment of the new artificial stars from Hubble Optics a few minutes ago. We will have the replacements on their way to our customers within the next couple of hours.
Thank you once again for your patronage, understanding, and patience.
Regards,
Manish
Agena AstroProducts
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Hi Kevin,
We have added a FAQ section in our web page to some common questions, here is a printable version:
http://www.hubbleoptics.com/files/Hubble5starFAQ.pdf
Of course, the star should be at least far enough to be within the travel of the focuser.
Hope it is helpful.
Best,
Tong
|
SilentLight
member
Reged: 11/29/08
Posts: 83
Loc: Los Angeles, CA
|
|
Manish/Tong,
Thank you for the excellent customer service.
 
|
Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
|
|
Hi Tong,
I received the new artificial star yesterday. You really go the extra mile for your customers. In this case, about 8000 extra miles!
Thanks,
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
7331Peg
professor emeritus
Reged: 09/01/08
Posts: 718
Loc: North coast of Oregon
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Manish,
Received my replacement today. Now, you really didn't have to do that since I modified the first one. However, I'll take your advice and use one of them for a flashlight, which will be handy.
You and Tong set a heck of an example for others by going far beyond what could be expected in shipping replacements to everyone. My hat's off to you!
John
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CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 2069
Loc: Morganton, GA, USA
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|
Tong:
Just have to add my own appreciation for the lengths you went to to take care of your customers - the modified unit arrived today. I'm sure it was a difficult decision, but I know it will pay off in the long run as you have earned many life-long customers by going above and beyond the call of duty!
--------------------
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KevinUK
Vendor (DSLR-AstroMod)
Reged: 08/22/07
Posts: 720
Loc: N 51'53 W 00'25
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Quote:
Hi Kevin,
We have added a FAQ section in our web page to some common questions, here is a printable version:
http://www.hubbleoptics.com/files/Hubble5starFAQ.pdf
Of course, the star should be at least far enough to be within the travel of the focuser.
Hope it is helpful.
Best,
Tong
Tong
I sent you an email but had no response as yet.
Two issues im grappling with:
1.
I have followed the advice about setting the distance of the star to the scope according to your given formula but I still cant seem to get the scope to focus, using both 10mm and 20mm eyepieces.
Are you sure the formula is correct? The reason I ask this is I have a Celestron C9.25. According to your formula my focus distance is only 7.25m!!
Normally without the star device focusing on just a terrestrial object in the distance outside, I cannot attain focus on anything at least less than 20-30m away, so for the star 7m seems awfully short?? 
2.
More worrying, as I don't have enough room to place the star in my garden I set up a mirror system, to double the distance from star to scope to assist in attaining focus.
I now am getting donut shaped stars from the device; when I come into focus the stars seem to rotate and deform into weird donut twisted shapes so determining collimation is impossible.
Is this an optical aberration due to the light path of the star->mirror->scope. You mention in your PDF that is hardly matters how the star is set up as long as its pointing in the general direction of the scope!
!!
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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|
Hi Kevin,
Sorry for the late response. Harold Suiter's book Star Testing Astronomical Telescopes will be very help (actually, a must have book) in this regards. The book actually do not recommend such a short distance (page 85), as the focuser tube normally does not allow such motions without extension tube or seriously vigneting the telescope. So the distance less than 20 times the focal length "are not recommended if they can be avoided"
But, what if this can not be avoided? Then you will have to try it out; start with 20 times focal length, you may need one or two extension tube(s), slowly go down to see how close you can go for your scope. The closer you go, the smaller the pinhole is required.
Best, Tong
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Kevin,
The mirror folding is an excellent idea, which I have tried and worked very well. But you do need a mirror/flat with optical quality, a dressing mirror will not work.
Best,
Tong
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Tamiji Homma
Pooh-Bah
Reged: 02/24/07
Posts: 1084
Loc: California, USA
|
|
Quote:
Tong:
Just have to add my own appreciation for the lengths you went to to take care of your customers - the modified unit arrived today. I'm sure it was a difficult decision, but I know it will pay off in the long run as you have earned many life-long customers by going above and beyond the call of duty!
I totally agree. Tong, you are 5 star vendor
Tammy
|
KevinUK
Vendor (DSLR-AstroMod)
Reged: 08/22/07
Posts: 720
Loc: N 51'53 W 00'25
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|
Quote:
Kevin,
The mirror folding is an excellent idea, which I have tried and worked very well. But you do need a mirror/flat with optical quality, a dressing mirror will not work.
Best,
Tong
Ahhh thats the problem then, cheap glass on the dressing mirror is no doubt the cause of the abberrations!
What type do you recommend?
--------------------
DSLR AstroMod
DSLR filter removal and replacement packages
http://www.dslrastromod.co.uk
-------------------------------
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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You may want to try this one:
http://www.surplusshed.com/pages/item/l3602.html
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Fred1
Pooh-Bah
Reged: 09/19/07
Posts: 1000
Loc: Garnet Valley, Pennsylvania
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|
That one is $100. Would this one work as well for $18? Or is it too small?
http://www.surplusshed.com/pages/item/pm1055.html
--------------------
Fred
Celestron 8" SCT w/Starizona Feathertouch Microfocuser/JMI Motofocus;
Stellarvue SV80ST Triplet APO
Tele Vue Binoviewers w/Orion Filter Wheel,Siebert Galaxy Viewer FR, Siebert 0x/1.3x MultiMag OCA
Earthwin Optical Binoviewers w/Pwr-Fltr Slide
Stellarvue BV3 Binoviewers w/Siebert 1.25x OCA
Celestron CG5-ASGT
Astro-Tech Voyager w/JMI Micro-Slew
Edited by Fred1 (05/25/09 08:21 PM)
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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You need a flat with a clear aperture at least about half of the aperture of your scope. So this one will work for a scope up to a 90mm aperture. Of course, a larger flat will be better for an easier setup and will also enable you to avoid the edge zone of the flat.
Edited by hubble-optics (05/25/09 08:58 PM)
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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|
Hi Kevin,
The formula M = 336 D / F^3 (D is in inch, F is the focal ratio) was derived by Roger W. Sinnott (Sky and Tel, May, 1991) based on Ray trace for Newtonian reflector, included in Suiter's book. Actually, as Suiter pointed out in his book (5.3.4), this will give "incorrect distance" for SCT. Suiter suggested M of 24 for a 8" f/10 SCT for a real star test. Our experience and Ray trace indicate that you do need at least this far for a real star test but not nearly as this far for an excellent collimation. To do a perfect collimation, you do need to go as far as to see the Airy disk! This has to be done by experiment for your scope.
However, you still can go much closer to do a (at least a preliminary)star test as long as you can focus on the star, and as long as you know what kind of impact/aberration the closer distance will introduce (yes, spherical aberration!)
We will make a clarification on this formula on our web site. Thank you for raising this question.
-Tong
Edited by hubble-optics (05/26/09 04:12 AM)
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dougspeterson
Pooh-Bah
Reged: 09/01/04
Posts: 1041
Loc: Murrieta, CA
|
|
I looked at Suiters book 2nd ed. that discusses the calculations around pg 90. I expected the distance to be a function of aperture only, but it turns out to be very sensitive to focal length. Why? Because long F# scopes have a large depth of focus and are therefore relatively insensitive to small amounts of abberation induced by a star at finite distance and the calculation seems to give intuitively silly numbers, but are just minimums. On the other hand a fast system has a very small depth of focus and the star needs to be much further away.
So there is no simple rule of thumb that works, like x times the focal length. It must be calculated.
--------------------
18" Dob
12" SCT
8" TMB F6 + Chromacor
6" F6 APM/LZOS Fluorite triplet, 32", 32lbs
2ea. 6mm singlets, one blind
"--Granted, that's a worse case scenario. The destruction might in fact be ... limited to our own galaxy."
Edited by dougspeterson (05/26/09 08:35 AM)
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Yes, it must be calculated (or tried out). It is determined by the spherical aberration of a nearby object for particular scope. There is an excellent explanation here:
http://www.telescope-optics.net/lower_order_spherical.htm#Wave_aberration_function
A simple OSLOing will reveal much more accurate information. E.g., to have the spherical aberration less than 1/4 wavefront, you need to put the star ONLY at 40 times focal length for the Hubble Space telescope. I am wondering why they did not do it then
Edited by hubble-optics (05/26/09 01:39 PM)
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Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
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Tong,
Quote:
to have the spherical aberration less than 1/4 wavefront, you need to put the star ONLY at 40 times focal length for the Hubble Space telescope. I am wondering why they did not do it then
My understanding is that the optical company that prepared the mirror figured it as a very fine paraboloid, but that no one thought to consider that it may deform to a different figure when in the zero gravity of space. In fact, in space the mirror "relaxed" to a spherical figure. You'd think somebody would've warned'em ....
Mike
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Mike,
It is really a fascinating story I can never learn enough! Actually, the star test has been used extensively (and exclusively, because it is the only test method available up there!) AFTER the HST had been launched into space to test and eventually to fix it. A great number of articles and reports have been written on this. Attached is the star test image and a vivid, but somehow sounds familiar, description by Burrows et al (http://articles.adsabs.harvard.edu//full/1991ApJ...369L..21B/L000021.000.html):
“… ,the left two columns (note that the first and third columns in the first two rows are not clear enough to be visible) show observed images of bright stars at two different scales, while the right columns show correspond models. The top two rows show images taken on each side of the nominal focus position. These images clearly demonstrate the presence of spherical aberration. Instead of a uniformly illuminated pupil image, the inner or outer edges are brighter”
-Tong
Edited by hubble-optics (05/27/09 05:57 AM)
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dougspeterson
Pooh-Bah
Reged: 09/01/04
Posts: 1041
Loc: Murrieta, CA
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|
Paraboloid relaxing into a sphere? That is an urban myth. An industry consultant who knew the people involved told me, the mirror was figured to the wrong asphere because of an incorrectly spaced null mirror set, so from day one it was doomed to disaster. It is said that an optical engineer with a ladder, flashlight and razor blade could have knife-edged and detected the problem at the center of curvature of the mirror. I actually know the name of the tech who made the initial error, but it doesn't matter, everyone makes mistakes, Perkin Elmer QA should have checked the work, the system failed the taxpayer. He used a metering rod to space two small mirrors, but instead of focusing on the ends of the rod as seen thru a hole in each protective cap he focused on the plastic cap itself, causing the spacing to be off by that <1mm thickness.
Edited by dougspeterson (05/27/09 08:07 AM)
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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Here is the NASA final report on this problem:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19910003124_1991003124.pdf
-Tong
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dougspeterson
Pooh-Bah
Reged: 09/01/04
Posts: 1041
Loc: Murrieta, CA
|
|
Fascinating, so it was the spacing error between one mirror and a field lens, creating .5 waves RMS, a huge error.
--------------------
18" Dob
12" SCT
8" TMB F6 + Chromacor
6" F6 APM/LZOS Fluorite triplet, 32", 32lbs
2ea. 6mm singlets, one blind
"--Granted, that's a worse case scenario. The destruction might in fact be ... limited to our own galaxy."
|
Sarkikos
Pooh-Bah
Reged: 12/18/07
Posts: 1051
Loc: Suburban Maryland
|
|
Good. Another urban myth laid to rest - at least here. I wonder where and how the myth started? Well, in any case, the mirror flaw was caused by an improperly setup null mirror test and the reliance on that test alone, rather making other types of tests and comparing the results. (Is there a moral here for amateur astronomers?) Both Perkin Elmer and NASA were ultimately culpable: the former for an incorrect test, the latter for lack of oversight. But the optical flaw was eventually corrected and we have had excellent astrophotography and discoveries as a result. Another reason for me not to do AP myself: I'd rather look at the Hubble photos.
--------------------
Celestron 10" f5 Newt on 1stBase (DSO)
Zhumell 8" f6 Newt, Bosma 6" f12 MCT (NSO)
6" f5 Newt, 130ST, 4.5" f4.4 Ball w/GLP, ST80 w/Crayford (RFTs)
C4-R (NSO/DS)
90mm f13 MCT (Luna/DS)
SkyMaster 25x100, 15x70
Zhumell 20x80
Barska XWA 10x50, 8x40
OptiView LPR 10x50
Const View 2.3x40
BV-125C
CG5, 2 drv / CG4, 2 drv, wood legs, ScopeStuff saddle / CG3, 1 drv
SV AZ / 501HDV on Bogen 055XB / P+ on Oberwerk
QuikFinder, Telrad
Orion Dynamo Pro 12, Dew-Not
Have GLP and not afraid to use it!
|
dougspeterson
Pooh-Bah
Reged: 09/01/04
Posts: 1041
Loc: Murrieta, CA
|
|
I think that particular myth started because the error was spherical abberation which one might naively assume is only caused by spherical mirrors, but as we all know can be caused by incorrect non -spheres. I remember seeing the highly technical phrase "spherical abberation" in a newspaper headline, the only time in our lives I think that will ever happen!
--------------------
18" Dob
12" SCT
8" TMB F6 + Chromacor
6" F6 APM/LZOS Fluorite triplet, 32", 32lbs
2ea. 6mm singlets, one blind
"--Granted, that's a worse case scenario. The destruction might in fact be ... limited to our own galaxy."
Edited by dougspeterson (05/27/09 09:14 AM)
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Larry Geary
professor emeritus
Reged: 09/24/06
Posts: 732
Loc: NJ, USA
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Weren't a number of the image processing and deconvolution algorithms used today by amateurs developed in an attempt to improve the Hubble images prior to the installation of COSTAR?
--------------------
The future is not set. There is no fate but what we make for ourselves.
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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This is getting more interesting…
Yes, indeed, a number of methods including the famous Roddier method have been used and further developed during the Hubble Aberration Recovery Program (HARP) organized by JPL (F. Roddier, C.Roddier, Appl. Opt. 32, 2993-3008, 1993)
Here is a description on how the star test was conducted with HST, “ …we requested that the highly defocused images be taken in flight by Hubble Space Telescope (HST) so that the method (the Roddier method) could be applied to estimate the exact amount of spherical aberration. Because defocusing the imaging also defocus the telescope tracking system (a kind of off-axis auto guider), it was not possible to obtain images sufficiently defocused for the method to apply. However, defocused images recorded by the HST are not blurred by the atmosphere and can be taken through narrow-band filter. In this case the wave-front information is still preserved and can be recovered by using phase-retrieval algorithm”
Even HST had trouble tracking a moving star while doing the star test!
Edited by hubble-optics (05/28/09 06:39 AM)
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Larry Geary
professor emeritus
Reged: 09/24/06
Posts: 732
Loc: NJ, USA
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|
My point - question, really - was that good things came out of the initial failure of Hubble. It was eventually repaired, but during the three years before the repair mission, much software was developed that improved results for ground based imagers, both professional and amateur.
A further question: Did all the development occur in the professional community, or did amateurs develop techniques that were adopted by professionals?
--------------------
The future is not set. There is no fate but what we make for ourselves.
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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|
Larry,
Make no mistake, regardless of the initial setback, HST has been the greatest telescope ever built. Yes, a great amount of good things came out the Hubble Aberration Recovery Program (HARP), not to mention the vast amount of knowledge learned after that.
We are still learning from this fascinating achievement as today!
Tong
Edited by hubble-optics (05/28/09 09:59 AM)
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groz
Pooh-Bah
Reged: 03/14/07
Posts: 1074
Loc: Duncan, BC
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|
Ok, just saw a reference to this thread from another forum. I saw the 5 star gadget mentioned elsewhere, and promptly went off to ebay to see it. What can I say, at that price, it was impossible not to hit the 'buy now' button. I cant praise the shipping / delivery enough, from your side of the pond, delivered to my doorstep in Canada, in less than a week. timing was very fortuitous, we were leaving for a weekend at a very dark location, and the little gadget arrived in the mail about an hour before we left.
My sct was collimated better than it's ever been that night, and, I did the collimation in broad daylight.
But, I do have a question now, after reading about the overheating issue on earlier ones. When mine arrived, the diffuser and the little 5 hole faceplate did fall out when I was putting in the batteries the first time. When re-assembling, should the black side be on the inside facing the leds, or on the outside facing the telescope? I'm wondering if the black paint is part of the 'heat fix', and, it needs to be inside? I put it the other way around when I re-assembled, and haven't noticed any problems yet, but if this is a problem, I'd like to pre-empt it now.
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jimarshall
sage
Reged: 03/20/07
Posts: 206
Loc: Virginia
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Quote:
Ok, just saw a reference to this thread from another forum. I saw the 5 star gadget mentioned elsewhere, and promptly went off to ebay to see it. What can I say, at that price, it was impossible not to hit the 'buy now' button. I cant praise the shipping / delivery enough, from your side of the pond, delivered to my doorstep in Canada, in less than a week. timing was very fortuitous, we were leaving for a weekend at a very dark location, and the little gadget arrived in the mail about an hour before we left.
My sct was collimated better than it's ever been that night, and, I did the collimation in broad daylight.
But, I do have a question now, after reading about the overheating issue on earlier ones. When mine arrived, the diffuser and the little 5 hole faceplate did fall out when I was putting in the batteries the first time. When re-assembling, should the black side be on the inside facing the leds, or on the outside facing the telescope? I'm wondering if the black paint is part of the 'heat fix', and, it needs to be inside? I put it the other way around when I re-assembled, and haven't noticed any problems yet, but if this is a problem, I'd like to pre-empt it now.
Yes, black to the inside.
--------------------
Jim
|
varmint
I invite more abuse
Reged: 02/10/07
Posts: 1209
Loc: Pacifica, CA, USA
|
|
Quote:
Hi Kevin,
The formula M = 336 D / F^3 (D is in inch, F is the focal ratio) was derived by Roger W. Sinnott (Sky and Tel, May, 1991) based on Ray trace for Newtonian reflector, included in Suiter's book. Actually, as Suiter pointed out in his book (5.3.4), this will give "incorrect distance" for SCT. Suiter suggested M of 24 for a 8" f/10 SCT for a real star test. Our experience and Ray trace indicate that you do need at least this far for a real star test but not nearly as this far for an excellent collimation. To do a perfect collimation, you do need to go as far as to see the Airy disk! This has to be done by experiment for your scope.
However, you still can go much closer to do a (at least a preliminary)star test as long as you can focus on the star, and as long as you know what kind of impact/aberration the closer distance will introduce (yes, spherical aberration!)
We will make a clarification on this formula on our web site. Thank you for raising this question.
-Tong
I picked one of these up from AgenaAstro (Manish), and got to play around during the day with my SCT. I setup my scope in the shade of my "porch", which is elevated about 10 ft above the sidewalk, and pointed down the street. I mounted this artificial star by taping it to my grab-n-go mount and had my kids tend to it while I setup and aligned.
I could clearly get everything in focus at >130ft, and had to us a 80mm extension tube when I pushed it close to 70ft, but it was really difficult to see any diffraction patterns because of the daylight. Now, I wasn't really expecting this to work in broad daylight, but I thought I read some had had success and figured to give it a try (and it was a way to keep the kids out of my wife's hair for an hour or so).
My question: can this be used in the daytime, but not out in daylight? Or do I have to wait for dusk? I'll give it a whirl at dusk tonight when the sun is not quite set, but our street is cast in shadow.
I'll also try and figure out how close I can get with my setup for those who may be interested in SCT land.
--------------------
Clear Skies,
Jim
--
"Do, or do not. There is no try."-Jedi Master Yoda
Scopes: CGE925, 80ED, NP127is (w/ADM acc.)
EPs: Naglers: 31, 22, 17, 9, 3.5 Pan’s: 15
Misc: Telrad, 2x&4x Powermate, Sol/OIII/UHC/Var Pol. Filters
Imaging Gear: Pentax K100D, SPC900NC
|
varmint
I invite more abuse
Reged: 02/10/07
Posts: 1209
Loc: Pacifica, CA, USA
|
|
Ok, I think I found a decent setup in my yard, even during the daylight I could see some diffraction rings on the brighter "stars" when 86 ft away (my son and I measured!)
I am attaching a crude composite photo (done in less than 10 minutes!) showing my setup to achieve this (sorry the afocal shot is pretty horrible, but you can easily make out 3 of the 5 "stars" in the EP I can see all 5). If 86 ft is too close then I can flip the scope to point up the street to the East and get as much distance as I want (I'll just have the neighbors wondering what the heck is going on and probably have to enlist my boys to tend the mount for that exercise).
--------------------
Clear Skies,
Jim
--
"Do, or do not. There is no try."-Jedi Master Yoda
Scopes: CGE925, 80ED, NP127is (w/ADM acc.)
EPs: Naglers: 31, 22, 17, 9, 3.5 Pan’s: 15
Misc: Telrad, 2x&4x Powermate, Sol/OIII/UHC/Var Pol. Filters
Imaging Gear: Pentax K100D, SPC900NC
|
varmint
I invite more abuse
Reged: 02/10/07
Posts: 1209
Loc: Pacifica, CA, USA
|
|
Wow, it really works, even at 86 ft. I just have to keep direct sunlight off the artificial star so there's enough contrast to see the "airy disc" and you're good to go. I can't wait to see it against the stars tonight, my scope was pretty decently (and quite noticeably) out of collimation. Now I feel it's pretty darn spot on.
--------------------
Clear Skies,
Jim
--
"Do, or do not. There is no try."-Jedi Master Yoda
Scopes: CGE925, 80ED, NP127is (w/ADM acc.)
EPs: Naglers: 31, 22, 17, 9, 3.5 Pan’s: 15
Misc: Telrad, 2x&4x Powermate, Sol/OIII/UHC/Var Pol. Filters
Imaging Gear: Pentax K100D, SPC900NC
Edited by varmint (06/21/09 11:35 PM)
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hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
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|
A great article by Greg Nowell: SCT Collimation under Adverse Circumstances
|
Preston Smith
Military Observer
Reged: 04/24/05
Posts: 3436
Loc: Eureka, Pa
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|
Just ordered one from Agena Astroproducts! 
--------------------
Preston
Lift your eyes and look to the heavens: Who created all these? He who brings out the starry host one by one, and calls them each by name. Because of His great power and mighty strength, not one of them is missing. Isaiah 40:26
SV115T,NHII,SV70,SV50 and Tele Vue Ranger
Vintage Refractors: Asahi-Pentax, Edmund Scientific, Tasco, Unitron
60mm Telescope Club
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
We proudly announce that Hubble 5-star Artificial Star has been featured in
(1) The New Product Showcase page (p.40) of the September issue of Sky & Telescope
(2) The July/August (Vol 3 Issue 4) of Astronomy Technoloy Today (http://astronomytechnologytoday.com) New Products Section (page 28)
Thank you for your continue support!
Tong
Hubble Optics
Edited by hubble-optics (08/20/09 04:00 AM)
|
drago
member
Reged: 01/11/08
Posts: 95
Loc: Latvia
|
|
this artifical star is can be possible to used for roddier tests?
--------------------
Sky-Watcher 100ed refractor on old HEQ5
Sky-Watcher 15075 refractor on EQ5 with motors
Orion Optics Europe 200 F6 newton
wo 66sd on modified synta AZ3
npz 8x50 seeker
18x50 beer bottle telescope
|
hubble-optics
Vendor (mirrors)
Reged: 05/02/07
Posts: 52
Loc: Arlington, VA
|
|
Sorry for the late response. Yes, absolutely.
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drago
member
Reged: 01/11/08
Posts: 95
Loc: Latvia
|
|
ok. try to test in this purpose too, in near future. today received subj
--------------------
Sky-Watcher 100ed refractor on old HEQ5
Sky-Watcher 15075 refractor on EQ5 with motors
Orion Optics Europe 200 F6 newton
wo 66sd on modified synta AZ3
npz 8x50 seeker
18x50 beer bottle telescope
|
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