JerryWise
Postmaster
Reged: 12/26/03
Posts: 7007
Loc: Lexington, SC
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Must be a simian (monkey) on my back!
Working with a replacement LX200R 10" the scope can be carefully collimated on outside focus. Move to inside focus and central obstruction shadow is off center. Carefully collimate on inside focus (just inside), get it perfect and move to just outside focus and CO shadow is off center indicating out of collimation.
The resolution seems fine but a standard collimation technique just will not work. Has anybody done a careful collimation of any size LX200R OTA and looked at the CO shadow just on the other side of focus?
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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NeoDinian
Experienced Postmaster
Reged: 10/05/05
Posts: 12227
Loc: Rockford Illinois
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Sounds like it may just be the mirror shift... Did you turn the focus knob back to match the other direction before testing? (ie: Last turn clockwise for both in and outside focus)
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Neo... (Jeff)
-=-=-=-=-=-=-
10" LX200-GPS/SMT UHTC "Draco"
 Rockford, Il.
NeoDinian's Eye on the Sky!
Coming soon:
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tboss70
Carpal Tunnel
Reged: 11/25/05
Posts: 2092
Loc: Missouri
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Is this another problem with the new tube Jerry? Just curious.
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Todd
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7007
Loc: Lexington, SC
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Yes Jeff, I understand collimation technique. I also have a number of SCTs and other scopes for comparison. Matter fact, I collimated 4 OTAs last night (including the LX200R) in order to do some more resolution testing. I got the other 3 collimated perfectly. Each scope is fine collimated with a FeatherTouch. Have you any experience on LX200Rs? I am looking for some hands on detail. 
Yes Todd. It may not be a problem but a type manifestation.
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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Gary
sage
Reged: 06/12/05
Posts: 357
Loc: Southeast, Ga
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Post deleted by Gary
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LX200R Gps8
LXD650, M????? 127EDT w/Moonlite
Meade EMC AR5
C/Vixen 102 Fluorite APO w/Moonlite CF2
C80ED (Orion 100ED, FS or Trade) needs painting.
LXD75 WO Megrez 90mm FD
GIRO II w/EQ6 Tripod (DSV-1, FS or Trade)
P/S R-2 Daig.
Meade DS2000 2090AT-TC(497Autostar) FS or Trade
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Joad
Wordsmith
Reged: 03/22/05
Posts: 12028
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All I know, Jerry, is that my very imperfect LX10 presents the same CO "shadow" on each side of focus when I collimate. My collimation efforts are never to "critical" standards, but I do not believe that I notice the problem that has hit you again. My point is that I believe you: you know darned well how an SCT should be collimated, so if your LX200R is acting differently, it must be different. Whether that means poorly designed or simply different, I certainly cannot say. You say the resolution is fine? Maybe it is just different, and you're the first SCT expert to notice the difference?
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7007
Loc: Lexington, SC
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Thanks Joad. I think you are right in that we may be on to a characteristic instead of problem. This is the third 10" LX200R with this problem on collimation. (Well actually the second.)
1. First LX200R 10" sent back to Meade with this collimation problem. Meade checked it out and sent it back as fixed.
2. Same problem on LX200R 10" sent back for exchange.
3. Hand picked replacement LX200R 10" has same collimation problem.
Thanks for all the replys. It is not a matter of collimating, more a matter of the size OTAs showing this problem. We know everyone with an SCT would check collimation before a astrophotography session or heavy visual session. Would like to hear other LX200R owners report their results along with the size OTA they have. LX200Rs only, no need for RCX results.
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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Moggi1964
Carpal Tunnel
Reged: 11/07/05
Posts: 2515
Loc: Madison. NJ. USA
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Jerry, I'm too afraid to change the settings on mine just now as the views are good (though maybe not perfect).
It's going back to Meade at the beginning of next month so I will fit the Bob's KNobs when it comes back and will have to recollimate then.
Sorry I can't be of help jusy now. Of course, I may change my mind as I have been known to fiddle with stuff (should see my computer).
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Morris
WO Megrez 80 ED F/7
WO 8x42 binoculars
Seymor Rosin F/4.5 Astrograph in the making
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gavinm
professor emeritus
Reged: 08/26/05
Posts: 572
Loc: Auckland New Zealand
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I haven't needed any collimation - just straight out of the box but..
the CO seems dead centre both inside and outside focus.
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Gavin
Mt Albert Grammar School Observatory
Auckland, New Zealand
http://www.mags.school.nz/astronomy/index.html
12" LX200R w/ UHTC
SBIG ST7-XME + CFW10
Skywatcher Equinox ED80 Pro (ADM dovetail)
+ other stuff
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7007
Loc: Lexington, SC
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Spent last evening re-running test again. Here is EMail sent to Dealer, Mike Fowler and Scott Roperts (Meade). (I understand under TOS their reply cannot be posted without their permission.)
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Hello Craig:
This LX200R 10" is better.
There still is the collimation manifestation. When the scope is collimated outside focus and then moved through focus to inside focus using a FeatherTouch focuser (to eliminate mirror shift or travel) the central obstruction shadow is offset indicating an out of collimation condition on inside focus. Meade's collimation instructions on previous scopes indicate the central obstruction shadow should be centered on inside and outside focus for proper collimation.
Here is a carefully compiled image of over 40 Canon 300D shots on a EIA 1956 test target and artificial star. Below the LX200R 10" sequence is a Celestron C-11 sequence under identical conditons taken a few minutes after the Meade sequence. While the resolution of the LX200R 10" looks good you have to wonder if it is optimized. This is the second OTA with identical collimation presentation. Can we get a deffinitive answer from Meade engineering saying the scope is optimized when collimated on one side of focus and off on the other.
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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steddyman
super member
Reged: 03/02/06
Posts: 169
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As you know Jerry I have the collimation pattern you describe on my LX200R.
I am somewhat confused though. I thought on your original post with this latest OTA you reported this collimation issue no longer existed and you had great imaging results with it.
Have you repeated your resolutions tests to see what the results are like now?
I think I am losing all hope now.
Steddyman
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Skywatcher 100ED2
Skywatcher HEQ5 Pro
Nikon D200
Sony HDR-HC1E
Philips Toucam Pro II
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7007
Loc: Lexington, SC
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Quote:
I am somewhat confused though. I thought on your original post with this latest OTA you reported this collimation issue no longer existed and you had great imaging results with it.
Have you repeated your resolutions tests to see what the results are like now?
Yes Steddyman, you are right in my original post. It was a hurried inspection and I wanted to get right to the resolution which showed a near perfect LX200R 10" vs the one sent back. I spent the time on resolution test and did not dig deeply down into the original collimation issue. The test last night were at a much higher magnification. My apologies about the confusion. But do not give up hope on the scope. I think a LX200R 10" with the collimation issue (based on the resolution test only) should best most similar sized SCTs out there.
The second OTA Meade sent, even with a small collimation offset on the other side of focus has great resolution. It easily paces the larger C-11 on these test. The LX200R optics will be or already are a winner. There is just some little manifestation of these optics that does not match the collimation presentation of other SCTs and it does not seem to hurt the resolution. I would just like for Meade engineering to say "its ok, collimate one side of focus, don't worry about the other side of focus and you will have the best the scope can offer".
That's all we need to be happy. Hang on till they answer.
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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Joad
Wordsmith
Reged: 03/22/05
Posts: 12028
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Wow, Jerry, it would not be possible to present a clearer, more complete demonstration of what you have been describing than what you show us in this thread. How odd it is: there is unquestionably a "flip" as you move through focus, yet the resolution results look excellent. Last night I carefully collimated my LX10 (star test at 285X) with your experience foremost in my mind, and I most certainly did not see the "flip" that you have been discussing in so many threads. (I did get nice resolution too!  )
So you have really discovered an interesting phenomenon (I use the word "phenomenon" deliberately, rather than "problem," because maybe that's all it is--though I'm not sure of that).
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Rlnd300
member
Reged: 01/02/06
Posts: 59
Loc: Louisiana USA
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Hi Jerry I was getting the same results with my 8 inch "R" until I collimated the inside of focus first, then the outside of focus, now the patterns are the same and the resolution is out of this world. It might be worth a try to see what happens.
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Roland Hebert
12" DBA Certified
Meade 114/NT 4.5" Newt.
20x80 Binos
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7007
Loc: Lexington, SC
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Roland, I gave that a try too. I see you have an 8". I suspect the 10" is just a hair different. I am getting excellent resolution on test targets. No star test yet until the sky clears. Thank you for the info on the 8". Another member said their 14" doesn't have the characteristic either. I don't recall seeing it in the 12" LX200R I had either. I did no indepth work on that one though. It had a lot of white grease in the baffle tube making reflections and it went back to Meade.
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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Rlnd300
member
Reged: 01/02/06
Posts: 59
Loc: Louisiana USA
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Jerry, I wish you the best in your adventures with Meade. I did some research before I purchased, and chose the 8" because of the weight. But I was real close to getting the 10. Hope you get this resolved.
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Roland Hebert
12" DBA Certified
Meade 114/NT 4.5" Newt.
20x80 Binos
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Jeff Young
Post Laureate
Reged: 08/04/05
Posts: 3260
Loc: Ireland
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Jerry --
I'm not sure I've got any help for the LX200R, but look at the collimation pictures you posted on the C11. Note that the tiny dot in the center of the secondary shadow isn't centered. As you get closer and closer to focus, you can see more and more clearly that the dot is off-center. Then in your infocus image, the star is showing what looks like coma (the dot is now slightly outside the star).
I *think* this means that your secondary isn't centered in the corrector. My 9.25 also has this problem, only a bit worse. I fixed it once, but I can't tighten the secondary holder enough without taking the corrector off, which I haven't gotten around to yet.
Anyway, if my suspicion is correct, then your C11 might deliver even better results with the secondary centered....
-- Jeff.
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Nikon 18x70s / UA Millennium Colorado:
Solarscope SF70 / TV Pronto / AP400QMD Coronado SolarMax40 DS / Bogen 055+3130
APM MC1610 / Tak FC-100 / AP1200GTO Tak Mewlon 250 / AP600EGTO
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physics911
super member
Reged: 02/28/06
Posts: 195
Loc: Indianapolis
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Jerry,
Just for a minute lets suppose the collimation issue is just the nature of this device. Of course it probably isn't but.... To what do you attribute the cause of the poor optics on the two previous scopes? Your new scope is light years ahead of your previous one as far as resolution yet it shows the same collimation issue.
Chris
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There is no such word as alot!!!
CGE
10" LX200R OTA
WO Megrez 90
Canon 300D
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Moggi1964
Carpal Tunnel
Reged: 11/07/05
Posts: 2515
Loc: Madison. NJ. USA
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Good question Chris!
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Morris
WO Megrez 80 ED F/7
WO 8x42 binoculars
Seymor Rosin F/4.5 Astrograph in the making
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chef_josh
member
Reged: 07/01/06
Posts: 22
Loc: New York
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Is it possible to use a laser collimator for a SCT?
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Meade ETX-90AT, LX200R 8"
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