Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Hi,
I'm thinking I need an OAG so I can guide in front of my filters / CCD, but behind the AO unit.
Anyone know if there are any options apart from the MOAG-A?
Thanks.
Brian
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12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Joseph Gillman
Carpal Tunnel
Reged: 12/06/05
Posts: 2976
Loc: Due south of the North Pole (A...
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Your compatriot Nick Cook is the one to ask.
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Hi Joseph,
I know what you mean, Nick has a reasonably similar setup and has been a great help. I'm hoping he might read this thread  But all ideas welcomed.
Seems to be limited options that are compatible with the AO unit in place. I quite liked the idea of the 9mm TSOAG9T2
http://www.teleskop-express.de/shop/product_info.php/language/en/info/p641_Off-Axis-Guider---nur-9mm-Baulaenge---T2-Anschluss---fuer-CCD.html
But it can't be mated with the AO unit.
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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Perhaps you can get Precise Parts to fabricate something for you?
Clear skies!
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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I've considered FLI's MOAG to shorten the back focus, but fitting it with the AO-L seems impossible...
Now, if only SBIG made a larger AO-8! 
In the mean time, this is the best I can do...
Clear skies!
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Space Photons Observatory
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Nick Cook
Pooh-Bah
Reged: 01/28/06
Posts: 1239
Loc: Somerset, England
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Hi Brian,
I'd defintitely look into an adapter for that guider. I love the fact it's such a low profile. If you can squeeze that into the optical path, you could have the dream setup. No more problems guiding through green filters! 
Keep us all posted. I may well be following your example on this if you succeed! Perhaps Precise Parts would consider a discount if they received a multiple order for that custom connector!
Nick
--------------------
Meade 14" RCX + Astro Physics 0.75 Reducer (27TVPH)
Meade 5000 ED80 APO (Guider/widefield)+ WO 0.8 Reducer
William Optics Zenithstar 66 Petzal
SBig STL11000M + AO-L + 3" Pyxis Rotator + 3" PDF Focuser 
Canon 20Da + IDAS Filter
Pulsar 9ft Dome
www.nick-cook.net
www.cavebear.co.uk
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Thanks all for your posts:
Never heard of Precise Parts before - but one google-search later, they now have an email enquiry from me! Thanks for the tip Wirelessdude.
BTW... errr, your set up off the back of your scope is awe inspiring! Is that your 6" scope? What counter-weights have you got? Do the city lights dim when you turn it on?
Hi Nick, yep, the 9mm low-profile does look good - especially as I get some vignetting already, so I don't really want to add too much more length to my image train. In my naivity it surprises me that I get the vignetting just with the STL 6303+AO-L on the AstroPhysics AD2003 and ADASCTLM27 2.7" adapters - isn't the later supposed to increase the clear aperature? - I presume with your bigger scope it's not an issue?
Regards,
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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Hmmm... After further looking into the German MOAG, it looks very promising! I can see slipping it into the STL/AO-L-only configuration. I'll have to measure to see if it would work with my FW8...
Clear skies!
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Space Photons Observatory
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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Nope... That's my 10" LX200R, soon to be replaced with my new, just-delivered 12" LX200R. I don't know how much current everything consumes (haven't put an ammeter onto it), but it is powered by a 300W Meanwell switched, regulated 12-15VDC/26A power supply set at 13.8VDC! ;o)
Clear skies!
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Space Photons Observatory
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Cool set up Wirelessdude - would love the rotator!
What's the German MOAG you refer to?
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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Oh, yeah! To answer your other questions... I have Losmandy "D" dovetails running the entire length of the OTA on the top and bottom. I have attached Losmandy counter weights at the front (4x 3.5-pounders). I expect to use less when I put the 12" OTA on the CGE mount, since it is rear-heavier than the 10" OTA, and will attempt to put the primary mirror at the DEC pivot this time (at least as close as I can get it...) ;o)
Clear skies!
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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The link for the 9mm TSOAG9T2 you provided. It is much thinner than FLI's version, I think. I am highly considering it!
See how informing each other works in these forums? ;o)
Clear skies!
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Space Photons Observatory
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Lol! No wonder I couldn't find it in the FLI website.
So let me get this right... you've just directed me to my own information??? Whhoooh! Well, that's my take on it
Still, I have to agree with myself, it does look interesting...
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12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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LLEEGE
Running out of Oxygen
Reged: 03/03/05
Posts: 9782
Loc: Cloud-chester,NY
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I checked one of those out at NEAF. Seems flimsy to be putting a heavy camera/CFW on. I think it was designed with DSLR's in mind.
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"Okay! You draw the straws. I'm-a taking the parachute."
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LLEEGE
Running out of Oxygen
Reged: 03/03/05
Posts: 9782
Loc: Cloud-chester,NY
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Here is the FLI OAG. A bit pricey. 
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"Okay! You draw the straws. I'm-a taking the parachute."
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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Thanks for the review and heads up, LLEEGE!
Clear skies!
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Nick Cook
Pooh-Bah
Reged: 01/28/06
Posts: 1239
Loc: Somerset, England
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Hi All,
I love it when we all start pooling knowledge like this. I'll have a chat with the guys at FLI about their guider and see if I can persuade them to produce the necessary adapters.
BTW, FLI have been brilliant at trying to sort out my focuser problems. Talk about fantastic after sales support, I can't recommend these guys highly enough.
Yeah Brian, I do get some vignetting, but not enough to make me worry.
Am I the only person not using the FW8??? Kit envy! LOL
Nick
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Meade 14" RCX + Astro Physics 0.75 Reducer (27TVPH)
Meade 5000 ED80 APO (Guider/widefield)+ WO 0.8 Reducer
William Optics Zenithstar 66 Petzal
SBig STL11000M + AO-L + 3" Pyxis Rotator + 3" PDF Focuser
Canon 20Da + IDAS Filter
Pulsar 9ft Dome
www.nick-cook.net
www.cavebear.co.uk
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LLEEGE
Running out of Oxygen
Reged: 03/03/05
Posts: 9782
Loc: Cloud-chester,NY
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Quote:
Hi All,
I love it when we all start pooling knowledge like this. I'll have a chat with the guys at FLI about their guider and see if I can persuade them to produce the necessary adapters.
BTW, FLI have been brilliant at trying to sort out my focuser problems. Talk about fantastic after sales support, I can't recommend these guys highly enough.
Yeah Brian, I do get some vignetting, but not enough to make me worry.
Am I the only person not using the FW8??? Kit envy! LOL
Nick
They have an in house ME who can design anything you need. But, they are pricey. Might be cheaper to use Precise Parts. FLI is great to work with and I'm lucky to be 20 miles away.
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"Okay! You draw the straws. I'm-a taking the parachute."
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Ok, LLEEGE - thanks for your input - I'm now nervous about going with the 9mm OAG - as you say, maybe it's not strong enough. I assume it is metal?
BTW I got a quick response back from PreciseParts - they reckon approx us$123 for an adapter to fit the AO-L and STL. Not certain they've understood the solution completely yet (although I did attach photos and technical diagrams of the AO-L and STL).
Maybe the FLI OAG is a better option - although the price is a killer - plus with the need to buy the SBIG Remote Head Guider - as apparently the AO-L won't work with my existing DSI Pro II Mono as the guide camera
Yikes, I'm having trouble selling this to myself, let alone she who must be obeyed...
Nick: it was a lot cheaper when I had my guiding problems. Now you've helped me resolve them, all these other temptations arise
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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WirelessDude,
Looking at your set up again, your autoguider is behind your AO-L on the MOAG: What is your guiding camera? It's not an SBIG Remote Guiding Head?
Are you not using the guider connected to the AO-L connected to your mount to bump the scope when the AO-L exceeds it max deflection?
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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WirelessDude
sage
Reged: 01/02/08
Posts: 254
Loc: San Tan Valley, AZ, USA
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Sorry... I should mention that this a test setup where I was trying all sorts of stuff! Typically, I would have the RGH connected in this configuration with the AO-L in order for the system to work. Sorry for the confusion! And, too bad the ST-402ME doesn't have an AO/SCOPE port...
Clear skies
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Space Photons Observatory
Astrophotography Equipment...
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Ok, I'm no closer to a solution, but my thinking (at least re requirements) is a bit clearer thanks to all the feedback:
- The off-axis guider must sit between the AO and the CCD camera so I can guide in front of the RGB filters and take advantage of the performance improvement from the AO unit.
- I do not want to use the Astrodon MOAG-A (a frequently recommended solution) as I'm concerned re (1) too thick (increasing vignetting???), (2) expensive (I might be able to sweet talk the missus...), and (3) non rotatable.
- The "solution" must have 2" clear aperture;
- Be thin to limit the length of the image train;
- Be adjustable (rotatable) while leaving the CCD position / angle unaffected;
- Not interfere with (sit in the view of) the main CCD chip; and
- Take the weight of the SBIG without flexing.
It would need to be able to mate with the AO-L and the CCD camera. If necessary I would be prepared to consider getting custom connections made if that was feasible.
Does anyone use / know if the Lumicon 2" Easy Guider is an option?
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Doug Sanqunetti
super member
Reged: 12/19/05
Posts: 174
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Hi Deskman,
There is a reason the MOAG is "thick". Remember the distance between the pick-off mirror and the main imaging chip must be the same as the distance between the pick-off mirror and your guide chip. Otherwise you will not be able to focus both the camera and the guider at the same time. One advantage the MOAG has is that a lens is available to shorten the distance between the pick-off mirror and the guide camera. I am uncertain whether the lens magnifies the image or not.
Here is another Off Axis Guider option for you http://www.sciencecenter.net/hutech/mitsub/oag.htm
I modified one of these mitsuboshi OAG's to fit my ST10-XME. I made a flat plate for the OAG which bolts the OAG directly to my AO-8. On the other side of the OAG, I originally put another flat plate that I intended to bolt directly to the CFW-8. I found that additional space was required between the OAG and the CFW-8 because the distance between the pick-off mirror and the guide chip was longer than the distance between the pick-off mirror and the imaging chip. My imaging train is as follows: ST10-XME, CFW8A, spacers, Off-Axis guider, and then the AO-8.
So far, I have only been able to test the setup inside with an artificial star, but I have been able to get both the imaging camera and the guide camera to focus with this setup.
Just to make sure everyone is aware, you must use the SBIG remote guide head as a guider with this setup. There is no way to make this work with a separate autoguide camera. At least none that I am aware of.
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http://www.dougsastro.net
Cicero, Indiana
Edited by Doug Sanqunetti (06/14/09 02:12 PM)
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Doug Sanqunetti
super member
Reged: 12/19/05
Posts: 174
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Here is a picture of the custom plate necessary to attach the AO-8 directly to the Mitsuboshi OAG. It was also required to drill and tap holes into the OAG to make this work.
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http://www.dougsastro.net
Cicero, Indiana
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Hi Doug,
Thanks for your posts - the Hutech looks quite good - and reasonably "thin" Also like your adapter.
I know the guide chip and imaging chip need to be at the same distance, but if the OAG can be as thin as possible that will (I assume) minimise any increase in vignetting experienced on the main chip, and any extra focus distance required for the guider can be accomplished through extensions... unless it's the other way around - which is what you are getting at!
Darn it! All these measurements and things get confusing!
The Huetech looks a good option though. I've emailed a few questions to them, and will need to get my tape-measure out to check distances...
Cheers,
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Doug,
When I started this thread I assumed I could use my DSI Pro II as the guider... in an email somewhere I was advised the RGH was required, another blow to the cash flow
Thanks for alerting all to the issue though as it was not immediately obvious to me and I guess others.
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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rat156
super member
Reged: 09/21/07
Posts: 100
Loc: Melbourne, Australia
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Hi Brian,
FWIW I have the "recommended" setup, and I don't think that the distance is much shorter with the other guiders. I haven't had much of a chance to test my setup out as the weather is not co-operating, but maybe tonight! I was planning on replacing the 8-32 grubscrews in the MOAG with 8-32 thumbscrews, this allows rotation of the imaging chip relative to the guide chip around the v-groove adapter.
Cheers
Stuart
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Hi Stuart,
Thanks for the post and the pic.
You're probably right about the distance thing... I'm just a bit paranoid about how much an extra inch or two will impact the vignetting. If I knew it was no real issue the choice would be a lot easier:)
The other issue is the ability to rotate the OAG - I get (and like) your idea, but I'm not sure that will work with the "L" shaped AO-L in place? - see pic below (ignoring the trendy belt-and-braces bungy cord!)
Well, I've orderd the SBIG Remote guiding head (took advantage of the $100 off sale price), so I'm gonna need to make an OAG choice soon otherwise I've got one expensive paper-weight
Clear (southern) skies,
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Ok, I've gone and done it... decided to go with the MOAG-A. I think Flats will deal with any extra vignetting. As for rotating, well, I'll get by for now (maybe a rotator in the future somewhere..? )
The RGH arrived today too - two days to get here from the US - not bad eh!
Thanks again for all the helpful advice.
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Nick Cook
Pooh-Bah
Reged: 01/28/06
Posts: 1239
Loc: Somerset, England
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Hey great stuff. Keep us posted!
Love the belts and braces approach of the bungee cords. Nothing like a like bit of extra insurance! Plus your RCX can double up as a mega catapult now!
Nick
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Meade 14" RCX + Astro Physics 0.75 Reducer (27TVPH)
Meade 5000 ED80 APO (Guider/widefield)+ WO 0.8 Reducer
William Optics Zenithstar 66 Petzal
SBig STL11000M + AO-L + 3" Pyxis Rotator + 3" PDF Focuser
Canon 20Da + IDAS Filter
Pulsar 9ft Dome
www.nick-cook.net
www.cavebear.co.uk
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Cheers Nick, as long as the thing being catapulted is not my camera et al  You can sense the type of DIY guy I am I suspect...
This hobby was much cheaper before I got the autoguiding problem sorted out - at least then there was no need for additional equipment
Looking forward to the challenges of tri-colour imaging now.
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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rat156
super member
Reged: 09/21/07
Posts: 100
Loc: Melbourne, Australia
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Hi All,
Well I finally had a chance to try the setup out last night...
The rotation of the RGH works OK, to a point. That point being the limits of the cable from the AO8 to the CFW. I have just had a look in the light and if I swap the two I2C cables around I'll have a bit more freedom. After all I only need 180deg. The only other problem is balance. I need to move the counterweights past the front of the OTA on my RCX! Which means off to the hardware store for me tomorrow to figure something out.
Cheers
Stuart
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Good result Stuart!
Definitely a win if you can rotate - the AO-8 is a bit more flexble that the AO-L in that respect.
Can you not add more weights rather than build an "extension" to your scope?
Brian
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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rat156
super member
Reged: 09/21/07
Posts: 100
Loc: Melbourne, Australia
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The problem with adding more weight is that it throws off the other axis, so I can balance vertically or horizontally now, but not both at the same time.
Now it's setup so that the tube is balance vertically, which means that the weight on the top and bottom of the scope is equal. When I shift off vertical, the plumbob effect of having so much weight a fair way off the back of the scope comes into effect. In order to counteract that I need to move the weight forward, or add more weight to the front. Which has just given me an idea, if I add equal amounts to the top and bottom of the scope at the front I won't stuff up the vertical balance and may correct the horizontal balance, yes???
Off to try that out.
Cheers
Stuart
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Deskman
super member
Reged: 09/22/06
Posts: 145
Loc: Devon, UK
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Difficult to visualise what your set up is.
Let us know how your experiment goes.
--------------------
12" Meade RCX 400
SBIG ST-L 6303E + AO-L
MOAG-A + SBIG Remote Guider
Astro Physics 27TVPH 2.7" Telecompressor
Astrodon 2" Tru-Balance E-Series LRGB Filters
Skywatcher Equinox 80ED 80mm refractor
Canon EOS 450D (unmodded...for now)
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Nick Cook
Pooh-Bah
Reged: 01/28/06
Posts: 1239
Loc: Somerset, England
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Quote:
The problem with adding more weight is that it throws off the other axis, so I can balance vertically or horizontally now, but not both at the same time.
Now it's setup so that the tube is balance vertically, which means that the weight on the top and bottom of the scope is equal. When I shift off vertical, the plumbob effect of having so much weight a fair way off the back of the scope comes into effect. In order to counteract that I need to move the weight forward, or add more weight to the front. Which has just given me an idea, if I add equal amounts to the top and bottom of the scope at the front I won't stuff up the vertical balance and may correct the horizontal balance, yes???
Off to try that out.
Cheers
Stuart
Hi Stuart,
I didn't catch whether you're using a 3D weight system. I use the ADM one and get great weight balance,clutch open and telescope holding position in nearly every axis. Getting good balance is key for those bump settings to work well.
Hope you get this sorted okay.
Best wishes,
Nick
--------------------
Meade 14" RCX + Astro Physics 0.75 Reducer (27TVPH)
Meade 5000 ED80 APO (Guider/widefield)+ WO 0.8 Reducer
William Optics Zenithstar 66 Petzal
SBig STL11000M + AO-L + 3" Pyxis Rotator + 3" PDF Focuser
Canon 20Da + IDAS Filter
Pulsar 9ft Dome
www.nick-cook.net
www.cavebear.co.uk
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rat156
super member
Reged: 09/21/07
Posts: 100
Loc: Melbourne, Australia
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Hi Nick,
I use an STH (Stuart Thomson Homemade) balance system. I made it from some Aluminium bits from the hardware store. Even with an ADM or Losmandy system I would need to put the counterweight out the front of the OTA. With the top and bottom weights I get nice balance and no extensions. I'll take some pics next time it's in action, hopefully soon!
Cheers
Stuart
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Nick Cook
Pooh-Bah
Reged: 01/28/06
Posts: 1239
Loc: Somerset, England
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STH - brilliant, look forward to the images!
Thinking about it I've got a Losmandy mount and a APO balancing the top of the OTA out. In the past I've had 3D weights on that as well, but don't need them anymore since I moved to the heavier STL camera.
Hey... maybe all you need to do is just need to add more kit! What an excuse for buying a really big APO and having it sticking out the front!
Nick
--------------------
Meade 14" RCX + Astro Physics 0.75 Reducer (27TVPH)
Meade 5000 ED80 APO (Guider/widefield)+ WO 0.8 Reducer
William Optics Zenithstar 66 Petzal
SBig STL11000M + AO-L + 3" Pyxis Rotator + 3" PDF Focuser
Canon 20Da + IDAS Filter
Pulsar 9ft Dome
www.nick-cook.net
www.cavebear.co.uk
Edited by Nick Cook (06/26/09 07:01 AM)
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chicot
sage
Reged: 09/30/08
Posts: 239
Loc: Liverpool, UK
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The ADM one? I have that and I think it's a 2D system not a 3D one. In fact, I've just ordered a new weight system so that I can get better balance in RA.
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Meade 10-inch LX200 classic
Williams Optics ZII80
Starlight Xpress SXV-H9
Starlight Xpress SX-AO Active Optics
Starlight Xpress Lodestar autoguider
Meade DSI III
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rat156
super member
Reged: 09/21/07
Posts: 100
Loc: Melbourne, Australia
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Actually you don't want it balanced in RA, it should always "lean to the East" so that the RA drive gears always stay meshed. I have several bits of lead in the East fork where the batteries would normally sit. I've had to add some extra via the miracle of Velcro onto the outside as well. For me that's the RHS as you view from the control panel, probably LHS for Northerners.
Cheers
Stuart
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chicot
sage
Reged: 09/30/08
Posts: 239
Loc: Liverpool, UK
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That's what I meant by "balanced" (my post wasn't specific enough). Yes, I've heard from several sources that it should always lean to the east for exactly the reason you mention. However, at the moment, when I unlock the axis it always swings towards the west (I think because the focuser, both standard and electric are on this side). My new weight system (arrived about an hour ago!) allows movement along the tube, up and down, and also rotation about it's axis so I should be able to adjust this so that I get it leaning to the East. Hopefully, I should see a difference in tracking performance once I've done this
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Meade 10-inch LX200 classic
Williams Optics ZII80
Starlight Xpress SXV-H9
Starlight Xpress SX-AO Active Optics
Starlight Xpress Lodestar autoguider
Meade DSI III
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Nick Cook
Pooh-Bah
Reged: 01/28/06
Posts: 1239
Loc: Somerset, England
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Quote:
The ADM one? I have that and I think it's a 2D system not a 3D one. In fact, I've just ordered a new weight system so that I can get better balance in RA.
Aha.. Yes of course you're quite right, brain fade on my part... two axis directions = 2D not 3D... I actually have a second set of weights to offset it in RA (giving me the equivalent of 3D weight balance). I must photograph it some time. Of course even so, you want to weight it slight for uphill, so the RA gear is always engaged (to avoid any slop during guiding). One excellent tip in the RCX hints and tips thread is to put weights in the battery compartments. That should work really well.
Nick
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Meade 14" RCX + Astro Physics 0.75 Reducer (27TVPH)
Meade 5000 ED80 APO (Guider/widefield)+ WO 0.8 Reducer
William Optics Zenithstar 66 Petzal
SBig STL11000M + AO-L + 3" Pyxis Rotator + 3" PDF Focuser
Canon 20Da + IDAS Filter
Pulsar 9ft Dome
www.nick-cook.net
www.cavebear.co.uk
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