Domerman
Just Lucky, I Guess.
Reged: 07/21/07
Loc: PA
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Advantages of side by side setup?
#2944243 - 02/23/09 04:40 AM
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What are the advantages of a side by side setup as opposed to a piggy back setup? Is it easier or harder to balance? Would it make a difference for two relatively small 80mm refractors?
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Samir Kharusi
Carpal Tunnel
Reged: 06/14/05
Loc: Oman
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Re: Advantages of side by side setup?
[Re: Domerman]
#2944266 - 02/23/09 05:54 AM
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Small 80mm refractors are only "small" on a heavy mount. Any mount behaves MUCH better when it is lightly loaded, eg at one quarter or even less than its design load. Loading a mount is not just a matter of weight. It matters even more how much the moment arm is. A very long refractor weighing, say, 10kg, would be much more unstable than a short SCT of the same weight on the same mount. Side-by-side mounting reduces the moment arm that the mount sees because the center of gravity of the combined OTAs is much closer to the mount's axes than if one OTA was mounted piggyback. That is the main advantage of side by side, and when you are dealing with heavy OTAs (eg myself with a C14 and a 6") then piggyback is just plain absurd, while side by side is still practical. The disadvantage of side by side is that it takes longer to balance on all axes, but that's only an extra few minutes once you get the hang of things. Piggyback has the advantages of lesser flex (given equal quality mounting accessories) and easier to get the scopes to point at more-or-less the same FoV. If you suspect that your mount is approaching its load limit, then the sensible choice is side-by-side. Hope that helps.
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TheMenace
sage
Reged: 10/21/08
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Re: Advantages of side by side setup?
[Re: Samir Kharusi]
#2944292 - 02/23/09 07:00 AM
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The side by side lets you mount 4 scopes instead of two.
 
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groz
Carpal Tunnel
Reged: 03/14/07
Loc: Duncan, BC
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Re: Advantages of side by side setup?
[Re: TheMenace]
#2944538 - 02/23/09 10:31 AM Attachment (277 downloads)
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Depending on how you do the configuration, there is another huge benefit for side by side. We bought dual saddle adapters for our two mounts. All of our telescopes have the same dovetail on them. We can mix and match in 'any old combination' by simply pulling one out of one of the saddles, and putting a different one in.
Here's a shot of or configuration a while back. Today, we have it set up a little different, the ST80 is beside the SCT. If you have multiple tubes, all on the same style of dovetail, then the dual saddle adapter method of side by side leaves you with a lot of flexibility swapping tubes around.
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jgraham
Postmaster
Reged: 12/02/04
Loc: Dayton, Ohio
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Re: Advantages of side by side setup?
[Re: groz]
#2944580 - 02/23/09 10:57 AM
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When mounting multiple telescopes I like to try and keep the scopes as close to the center of mass as possible, this reduces the moment of inertia, the amount of counterweights needed, and the overall weight. To accomplish this I use side-by-side as much as possible.
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Canadian
Vendor
Reged: 01/11/05
Loc: Calgary, AB, Canada
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Re: Advantages of side by side setup?
[Re: TheMenace]
#2946135 - 02/24/09 03:27 AM
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Quote:
The side by side lets you mount 4 scopes instead of two.
How many?
 
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DennisF
Pooh-Bah
Reged: 03/03/06
Loc: Northern IL
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Re: Advantages of side by side setup?
[Re: Canadian]
#2946144 - 02/24/09 03:37 AM
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That's the most impressive grab n go setup I've ever seen.  BTW, how many therapy sessions do you have left? 
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alanon
Nobody tells me anything
Reged: 06/29/07
Loc: Las Vegas
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Re: Advantages of side by side setup?
[Re: Canadian]
#2946145 - 02/24/09 03:40 AM
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I am Speechless!
You are going to poke your eye out one of these days. 
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alanon
Nobody tells me anything
Reged: 06/29/07
Loc: Las Vegas
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Re: Advantages of side by side setup?
[Re: alanon]
#2946147 - 02/24/09 03:44 AM
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Question:What kind of scope are you interested in buying sir??
Your answer: Wi Wi Wi Wi Wi Wi Wi William Optics.
The sales rep didn't realize you had a speech impediment. 
Edited by alanon (02/24/09 03:55 AM)
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ibase
Vendor Affilliate
Reged: 03/20/08
Loc: Manila, Philippines 121*E 14*N
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Re: Advantages of side by side setup?
[Re: alanon]
#2946173 - 02/24/09 04:11 AM
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Any feelings of guilt at having 4 scopes have been completely obliterated. Thank you sooo much Garry!!! 
Best,
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TheMenace
sage
Reged: 10/21/08
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Re: Advantages of side by side setup?
[Re: ibase]
#2946189 - 02/24/09 05:01 AM
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Do I see refractor freak?
The tears involved when that setup gets knocked over?
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Lord Beowulf
Pooh-Bah
Reged: 10/13/08
Loc: Cedar Park, TX
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Re: Advantages of side by side setup?
[Re: Canadian]
#2946223 - 02/24/09 06:22 AM
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How the heck do you get that many heads that close together? You must have a really close knit family! 
Beo
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AlienFirstClass
Vendor
Reged: 02/13/09
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Re: Advantages of side by side setup?
[Re: jgraham]
#2946802 - 02/24/09 11:59 AM
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Quote:
When mounting multiple telescopes I like to try and keep the scopes as close to the center of mass as possible, this reduces the moment of inertia, the amount of counterweights needed, and the overall weight. To accomplish this I use side-by-side as much as possible.
How do you deal with a side by side arrangement when you only have one tube attached?
Counterweights?
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LLEEGE
True Blue
Reged: 03/03/05
Loc: Cloud-chester,NY
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Re: Advantages of side by side setup?
[Re: AlienFirstClass]
#2946821 - 02/24/09 12:04 PM
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Quote:
Quote:
When mounting multiple telescopes I like to try and keep the scopes as close to the center of mass as possible, this reduces the moment of inertia, the amount of counterweights needed, and the overall weight. To accomplish this I use side-by-side as much as possible.
How do you deal with a side by side arrangement when you only have one tube attached?
Counterweights?
Remove the double saddle.
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: LLEEGE]
#2946859 - 02/24/09 12:19 PM
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Quote:
How do you deal with a side by side arrangement when you only have one tube attached?
Quote:
Remove the double saddle.
Or, in my case, slide the side by side plate to position the single tube over the mount.
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CounterWeight
Postmaster
Reged: 10/05/08
Loc: Cloudyopolis, OR.
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2946973 - 02/24/09 01:22 PM
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Garry, quite an eyepiece turret there WOW.
I am thinking of going in this direction (side by side) with my CGE, and also have a bunch of questions. Soup to nuts really. I was looking at Cassidy products and there was a triple plate that got me thinkin'...Taks on the outboard and the 80ed 'tween...
Looking through the CGEM manual I saw there was a setting for this type setup... what needs to be done differently to accomplish this on a CGE? Or should I ask how are folks doing this on a CGE? Who all makes saddle plates and all the goodies? Thanks.
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TheMenace
sage
Reged: 10/21/08
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Re: Advantages of side by side setup?
[Re: CounterWeight]
#2946980 - 02/24/09 01:26 PM
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I'm guessing there is at least $2000 just in mounting accessories.
ADM
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: TheMenace]
#2946998 - 02/24/09 01:34 PM
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I'm guessing there is at least $2000 just in mounting accessories.
A couple hundred bucks will net an adjustable side by side plate from ADM or Losmandy.
The reason the CGE has a setting for SBS use is that, unlike nearly every other GEM, it incorporates a DEC index switch. This means that, unlike nearly every other GEM, it knows that it has been set up "sideways". When they were originally shipped, there was no such setting and no need for one - an offset of 90 degrees would be entered by the operator to tell the mount about the new initial position and everything worked fine. That's how mine was, at least. Later, folks started having problems with SBS setups, possibly due to firmware changes in later models, or perhaps just a misunderstanding of the DEC offset setting. I never owned a later one, so I have no way of being sure about that. Now they've added the SBS setting to make it work again (or, perhaps, just to make it easier to make it work).
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mclewis1
Thread Killer
Reged: 02/25/06
Loc: New Brunswick, Canada
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Re: Advantages of side by side setup?
[Re: CounterWeight]
#2947022 - 02/24/09 01:49 PM Attachment (146 downloads)
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Jim,
You'll need a Losmandy D type side by side sold by Cassidy, Losmandy or ADM. The Cassidy is the triple as you know, the Losmandy and ADM are doubles.
First think about the spacing, with a C11 there is not a lot of room beside it on the Losmandy or ADM setups. I have a TMB115 beside my C11 and there is maybe another inch between them. It will depend on which tubes, the type of rings and where they are mounted. Generally you want the heaviest tube(s) over the center of gravity and as close to the mount as possible, not hanging far out on a lever. Think about which side your tube rings open and close on, it's usually a function of which way you slide a plate into the saddle ... but you should think about it.
Also think about the saddle type on the side by side, I prefer a saddle that I can tip in from the side rather than having to only slide a scope in from the end.
Balancing is the key to setting up and using a side by side configuration. You need to balance side to side (sliding the cross bar back and forth in the stock saddle) and then each scope back and forth in their own saddles and then the standard balancing with the mount's counterweight. It sounds complex but like anything with a little practice it comes fairly naturally. It also helps and makes things go much faster to take notes and/or mark the bars with the popular configurations.
Smaller scopes with vixen compatible rails can be handled with an adapter in one of the D type saddles or in the case of the triple you may permanently bolt a vixen compatible saddle into one of the positions.
On a CGE you'll need either the latest HC firmware (4.15) or the ADM CGE adapter (which rotates the side by side mounting bar another 90°). The clutch levers stick up a bit on the CGE which means you can't easily just slide the side by side setup out of the stock saddle ... on my ADM setup I need to remove one of the saddles to do this, so I tend to leave my scope setup in its side by side configuration.
Here is a shot of my setup (without the ADM CGE adapter in place), notice the spacing between the scopes and that the C11 is positioned closer over the original saddle because it weighs more than the refractor.
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Domerman
Just Lucky, I Guess.
Reged: 07/21/07
Loc: PA
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Re: Advantages of side by side setup?
[Re: mclewis1]
#2947151 - 02/24/09 02:46 PM
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I want to use the ADM side by side setup, but I do not want to use the three point adjustable rings offered by ADM. What type "clam shell" rings would I need for an ST80 and Orion 80ED so that I can attach them to the ADM saddle and which dovetails would I need?
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TheMenace
sage
Reged: 10/21/08
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Re: Advantages of side by side setup?
[Re: Domerman]
#2947192 - 02/24/09 03:08 PM
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We need to know which mount you have,and which dove tail you are currently using or wanting to use.
ADM has side by side plates that fit losmandy,vixen,EQG etc.
They have any option you could possibly want,and will make you something if they don't already make it.
Great stuff!
losmandy to losmandy
vixen to vixen
adapter vixen to losmandy
dual saddle EQG
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Domerman
Just Lucky, I Guess.
Reged: 07/21/07
Loc: PA
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Re: Advantages of side by side setup?
[Re: TheMenace]
#2947199 - 02/24/09 03:11 PM
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Oh, I'm sorry I forgot to mention. I don't have the mount yet, but I'm planning on purchasing the Sirius EQ-G.
I'm pretty sure I need the vixen saddle but I do not know which rings I need for my two refractors.
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TheMenace
sage
Reged: 10/21/08
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Re: Advantages of side by side setup?
[Re: Domerman]
#2947327 - 02/24/09 04:13 PM
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The scope will most likely come with rings and vixen dove tail,but if you buy used,you may need to buy extra sets.
http://www.scopestuff.com/ss_rings.htm
http://www.scopestuff.com/ss_scops.htm
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Domerman
Just Lucky, I Guess.
Reged: 07/21/07
Loc: PA
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Re: Advantages of side by side setup?
[Re: TheMenace]
#2947349 - 02/24/09 04:19 PM
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Will these rings screw on to this ADM dovetail?
http://www.admaccessories.com/ADM%20Products/VDUP.htm
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Trebor777
Hazy
Reged: 01/04/08
Loc: Connecticut - U.S.
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Re: Advantages of side by side setup?
[Re: Domerman]
#2947433 - 02/24/09 05:24 PM
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Don't mean to jump in here - but I am.
Would it make more sense for me to piggyback (which I have been doing) my AT80ED on my SN10 (on Atlas EQ-G) or to mount them side by side.
The SN10 is a beast, while the AT80ED looks like a finderscope on it. I'm thinking that side by side would make balancing more of a pain. If I had 2 similar size scopes, side by side would definitely make more sense, but the difference between the 2 sizes has me questioning - hence my question.
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: Trebor777]
#2947629 - 02/24/09 07:15 PM
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Quote:
If I had 2 similar size scopes, side by side would definitely make more sense, but the difference between the 2 sizes has me questioning - hence my question.
Balance is balance. There's no difference between balancing two identical loads and balancing two widely dissimilar ones. The dual plate is positioned wherever it needs to be to place the center of gravity over the DEC axis.
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TheMenace
sage
Reged: 10/21/08
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Re: Advantages of side by side setup?
[Re: Domerman]
#2947723 - 02/24/09 07:58 PM
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Will these rings screw on to this ADM dovetail?
http://www.admaccessories.com/ADM%20Products/VDUP.htm
The holes make mounting the dove tail pretty easy.
The clam shell rings have threads to accept bolts from underneath,through the dove tail.
The link you provided should work fine as long as you use the holes outside the mounting head of the mount,as they protrude on the underside of the dove tail.
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CounterWeight
Postmaster
Reged: 10/05/08
Loc: Cloudyopolis, OR.
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2947726 - 02/24/09 08:01 PM
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John, mark, everyone,
Thanks for the answers ... great informational thread. Steve thanks for asking the question.
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Samir Kharusi
Carpal Tunnel
Reged: 06/14/05
Loc: Oman
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Re: Advantages of side by side setup?
[Re: CounterWeight]
#2948153 - 02/25/09 12:30 AM
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Quote:
Garry, quite an eyepiece turret there WOW.
I am thinking of going in this direction (side by side) with my CGE, and also have a bunch of questions. Soup to nuts really. I was looking at Cassidy products and there was a triple plate that got me thinkin'...Taks on the outboard and the 80ed 'tween...
Looking through the CGEM manual I saw there was a setting for this type setup... what needs to be done differently to accomplish this on a CGE? Or should I ask how are folks doing this on a CGE? Who all makes saddle plates and all the goodies? Thanks.
I would not load up a CGE too much if one of the OTAs is already a C11. The Casady saddles are for serious stuff, heavy enough to cope with even a couple of C14s. They are heavy, before you put any OTA on. So I would suggest that you restrict yourself to a C11 plus something very light, otherwise you are just destroying the performance of the CGE unnecessarily. For minimal weight you could consider a kangaroo joey arrangement, C14 with an autoguider under it, on a CGE:
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t.r.
Post Laureate
Reged: 02/14/08
Loc: Upstate NY
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Re: Advantages of side by side setup?
[Re: Samir Kharusi]
#2948431 - 02/25/09 07:43 AM
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With the ADM side-by-side plate, is there only a 10" center to center or is there a longer one? The C-11 with a 115mm leaves an inch of clearance, could I get a 120mm tube in there???
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t.r.
Post Laureate
Reged: 02/14/08
Loc: Upstate NY
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Re: Advantages of side by side setup?
[Re: t.r.]
#2948432 - 02/25/09 07:44 AM
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Add: I'd like to mount a C-11 with the 130GT on the CGE...
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: t.r.]
#2948439 - 02/25/09 07:51 AM Attachment (44 downloads)
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Quote:
With the ADM side-by-side plate, is there only a 10" center to center or is there a longer one? The C-11 with a 115mm leaves an inch of clearance, could I get a 120mm tube in there???
I don't remember the center to center distance of the Losmandy DSBS, but I had no problem mounting a C11 beside a VX120NA on that. I could have gone bigger yet (those three point adjustable rings add quite a bit of diameter; I believe they were 160mm ID).
Edited by jrcrilly (02/25/09 07:54 AM)
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JerryWise
Postmaster
Reged: 12/26/03
Loc: Lexington, SC
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Re: Advantages of side by side setup?
[Re: Canadian]
#2948502 - 02/25/09 08:48 AM
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The side by side lets you mount 4 scopes instead of two.
How many?
Just plain wow. I've never seen so many Takahashis on one mount..... ever. Way to go. (I think one buried in the center is in backwards. Of course that could be a super widefield setup.)
DISCLAIMER: This was subtle humor. No brand slam intended or implied. While white is used by Tak I know full well the white scopes are Astro-Physics models. Take the humor with a grain of salt.
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t.r.
Post Laureate
Reged: 02/14/08
Loc: Upstate NY
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Re: Advantages of side by side setup?
[Re: JerryWise]
#2948764 - 02/25/09 11:22 AM
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Thanks John C, just what I needed...do you think the mount would be fine pushing 15#GT + 27#C11 +5#accessories or too much in side by side mode?
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t.r.
Post Laureate
Reged: 02/14/08
Loc: Upstate NY
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Re: Advantages of side by side setup?
[Re: Domerman]
#2948774 - 02/25/09 11:28 AM
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Another question, the way the DSBS goes on the mount, requires the slot to be 90 degrees from polar, does this not throw off the encoders for GoTo???
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JerryWise
Postmaster
Reged: 12/26/03
Loc: Lexington, SC
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Re: Advantages of side by side setup?
[Re: t.r.]
#2948797 - 02/25/09 11:39 AM
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Quote:
Another question, the way the DSBS goes on the mount, requires the slot to be 90 degrees from polar, does this not throw off the encoders for GoTo???
Good question. That very thing gave me a fit on the CGE. There are a number of threads dealing with that on the CGE. AP mounts it doesn't bother in the least. Well, there is the issue of orthogonal alignment which seems to crop up more on side by side mounting. This is where the scopes always point a little higher or lower than the true polar axis when moving from east to west. Especially on a double plate. This will nick the gotos even on the best of mounts. You can shim it out but if you change scopes a lot the shimming takes more time than dealing with it. I always sync on a bright star near a new object anyway do the gotos are always dead on regardless of orthogonal alignment.
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t.r.
Post Laureate
Reged: 02/14/08
Loc: Upstate NY
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Re: Advantages of side by side setup?
[Re: JerryWise]
#2948802 - 02/25/09 11:42 AM
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So for the CGE Jerry, you sync each time before a move...I did read somewhere there is a feature in the Hand Controller to set it up to read Side by side...anyone doing this and elaborate please?
Edited by t.r. (02/25/09 11:43 AM)
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CounterWeight
Postmaster
Reged: 10/05/08
Loc: Cloudyopolis, OR.
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Re: Advantages of side by side setup?
[Re: JerryWise]
#2948831 - 02/25/09 11:52 AM
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Not sure if I'll be using the sxs setup with the C11, I am more interested in using for the refractors, am just plain uncomfortable with them that high riding on the C11... had my 102 on top and it worked perfectly. But the 128 or especially the 130... 'nyet - ne hachoo'(no-I dont want).
Of course having the C11 an option doesn't hurt, and I'd be all about a solution that includes more than excludes, like t.r. posted, a C11 with a 128/130, and an 80 somewhere sounds pretty good too. Sure it's loading the mount a bit bit I think the CGE will tote it.
I am liking these refractors so much ... the SCT hasn't seen much light lately - other than some CCD testing I've been almost exclusively using the 128 and 130 with the 80.
Another question - what if I dont want to use 3 pointers and just go with any of the clamp rings... are 3 pointers really necessary? Is that to make one for aligment scope?
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mclewis1
Thread Killer
Reged: 02/25/06
Loc: New Brunswick, Canada
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Re: Advantages of side by side setup?
[Re: t.r.]
#2948832 - 02/25/09 11:53 AM
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My "about one inch of clearance" comment was from the edge of the split rings. Different scopes with different rings will all be, well, different in the spacing available.
The ADM and Losmandy side by side setups are 10" center of one saddle to the other. The plate is actually 14" wide so if you had a very tight configuration you could easily drill a couple of different mounting holes for the saddle a little farther apart.
47 lbs is not too much for a CGE visually, but it's more than I would be comfortable with if I was imaging with the C11. I could probably make it work but it's not something that I'd plan to do on a regular basis. When I image with the C11 I replace the 115mm refractor with an 80mm autoguiding setup, this saves about 7 lbs or so. It might be even better to consider Samir's suggestion of a very minimal autoguider (something in the 50-60mm range, much like the KWIK package from KW Telescope KWIK ).
The issue with the 90° setup is that the CGE has home position switches (and therefore unlike the CG5 and CGEM knows when it starts out 90° from it's home position) and requires a Declination offset to be entered into the HC. Early fimrware seemed to handle this, and as John mentioned later versions seemed to mess it up. Today there are two simple fixes, one is to purchase the ADM CGE adapter which rotates the stock saddle 90° or simply use the new 4.15 firmware which has a specific capability to handle side by side setups.
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t.r.
Post Laureate
Reged: 02/14/08
Loc: Upstate NY
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Re: Advantages of side by side setup?
[Re: mclewis1]
#2948885 - 02/25/09 12:27 PM
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Thanks Mark, I'm visual only...It would be a Killer rig!
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jtaylor996
scholastic sledgehammer
Reged: 09/02/08
Loc: North Texas
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2951247 - 02/26/09 03:40 PM
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Balance is balance. There's no difference between balancing two identical loads and balancing two widely dissimilar ones. The dual plate is positioned wherever it needs to be to place the center of gravity over the DEC axis.
I disagree. You need more of a lever for dissimilar loads, which requires a longer arm, and thus a greater polar moment of inertia. Mass distribution counts when it comes to applying motor torque...
In this case (2 very different weights at a larger distance between them), it's probably not as large a difference as the difference between having 2 similar weights close versus 2 similar weights far apart. However, it's still there.
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: jtaylor996]
#2951286 - 02/26/09 03:58 PM
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Balance is balance. There's no difference between balancing two identical loads and balancing two widely dissimilar ones. The dual plate is positioned wherever it needs to be to place the center of gravity over the DEC axis.
I disagree. You need more of a lever for dissimilar loads, which requires a longer arm, and thus a greater polar moment of inertia.
I can't see that - and none of my side by side setups ever worked that way. The spacing is what it is, determined by the side by side plate. The most commonly used SBS plate is the Losmandy, at 10" spacing. It doesn't matter how much weight I place on either side - the length is 10".
None of that is relevant to balancing, anyway. If the SBS plate were 20" long the DEC inertia when in operation would be greater, but the process of balancing would be identical - place the COG over the DEC axis. Inertia and lever arm, by the way, are reasons to avoid over-and-under rigs. The increased distance between the top of the taller payload and the bottom of the increased counterweight load is more substantial, and affects the more critical RA axis.
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jtaylor996
scholastic sledgehammer
Reged: 09/02/08
Loc: North Texas
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2951371 - 02/26/09 04:46 PM
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I agree that most are going to be limited by the standard spacing of the available SBS setups (btw, ADM is also 10"); but that's nothing a drill can't solve
I also agree it's not relevant to the actual process of balancing the SBS setup once the offset is fixed.
The point I'm trying to make is that balance isn't just balance. One balanced setup can be better than another balanced setup, based on polar inertia.
I didn't mean to offend. I probably could have been more specific in the original post about what part I was disagreeing with. I'll have to admit that some of my eagerness to point this could possibly have something to do with the fact that I track a car that has the engine mounted completely behind the rear wheels... I spend a lot of time fighting the polar moment trying to maintain the same balance.
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Timber
professor emeritus
Reged: 11/08/08
Loc: SW foothills of Mt. St. Helens
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Re: Advantages of side by side setup?
[Re: Canadian]
#2956904 - 03/01/09 01:42 PM
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Hi Gary,
I gather that the GT-One is no longer being produced, what is the rated weight limit on your two mounts?
Thanks, Richard
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David Pavlich
Transmographied
Reged: 05/18/05
Loc: Mandeville, LA USA
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Re: Advantages of side by side setup?
[Re: Timber]
#2959959 - 03/02/09 10:46 PM
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Here's my take. First, on the last CGE I had, you could use a SBS setup and can tell the mount that there's an offset. HOWEVER, when you do a typical alignment routine, 2 west and cone error east, the mount thinks the offset is cone error and the east side slews exactly 90° from where it should. I tried everything, but it won't do a 2 star/cone error stars alignment. It does the first 2 just fine, but not the other side. So, to solve the problem, ADM makes an adapter that allows a SBS setup with the CGE pointed in its normal position. It works well, but it adds weight.
And as far as balance goes, especially with two very diverse scopes, it's just about impossible. What I finally had to do was decide which side of the meridian I was going to view on and balance it there. And with a CGE, the Dec motor will tell you in no uncertain terms if you're stuff isn't balanced.
Paul Burke solved it by using a triple setup. He placed the heavy scope (SC) right over the mount and the two outers scopes (refractors) outboard. And if you want to argue the case, call Larry at Mountain Instruments. He's dead set against SBS because there's no way you can get the balance correct.
So....I have a TMB 80/480 piggybacked on a 12" LX200 and it balances easily. 
David
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Blixx
professor emeritus
Reged: 12/02/07
Loc: CO. Aurora, USA
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Re: Advantages of side by side setup?
[Re: David Pavlich]
#2959996 - 03/02/09 11:12 PM
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Hi all,
I hope that this is not off topic. I am getting a Skywatcher EQ6pro and am thinkg of going the SBS way with my SVP100 and my C80ed. I have read through this thread and have not seen what I would need to get for this mount. Can anyone help me with this. Thanks,
Dan
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mclewis1
Thread Killer
Reged: 02/25/06
Loc: New Brunswick, Canada
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Re: Advantages of side by side setup?
[Re: Blixx]
#2960151 - 03/03/09 01:27 AM
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Dan,
If you are going to stay with the smaller vixen compatible rails try one of the following ...
ADM VSBS http://www.admaccessories.com/ADM%20Products/VSBS.htm
Losmandy VSBS http://www.losmandy.com/v-series.html
Scopestuff DMD6 http://www.scopestuff.com/ss_dmd6.htm
Or you could upgrade the stock EQ6 saddle to a more robust D type saddle from ADM
ADM saddle EQG-SAD http://www.admaccessories.com/ADM%20Products/EQG-SAD.htm
and then one of the following ...
ADM LSBS http://www.admaccessories.com/ADM%20Products/LSBS.htm
Losmandy DSBS http://www.losmandy.com/secondary.html
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Chris Rowland
professor emeritus
Reged: 02/28/05
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Re: Advantages of side by side setup?
[Re: mclewis1]
#2960426 - 03/03/09 08:26 AM
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The new handcontrol software for the Celestron GEMs has a Mount orientation option that helps with a side by side setup where the OTAs are at right angles to the normal orientation.
Escape to the menus, find the mount Orientation option and set it to East or West.
Then do the alignment normally.
Chris
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Blixx
professor emeritus
Reged: 12/02/07
Loc: CO. Aurora, USA
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Re: Advantages of side by side setup?
[Re: Chris Rowland]
#2960633 - 03/03/09 10:30 AM
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Thanks Mark. So does anyone know if the Skywacher EQ6-pro has an option to orientate to scopes to the east west direction. if i'm correct, the scopes would be in this position. If it doesn't how do you correct for this?
Dan
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: Blixx]
#2960742 - 03/03/09 11:29 AM
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So does anyone know if the Skywacher EQ6-pro has an option to orientate to scopes to the east west direction.
Like most mounts, it has no way of knowing that you have rotated it before alignment so there's no need to do anything. There's no index switch. The CGE is a rare exception to this.
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CounterWeight
Postmaster
Reged: 10/05/08
Loc: Cloudyopolis, OR.
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2960795 - 03/03/09 11:46 AM
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Does the CGE Pro also have limit switches like the CGE? Just curious.
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Blixx
professor emeritus
Reged: 12/02/07
Loc: CO. Aurora, USA
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Re: Advantages of side by side setup?
[Re: CounterWeight]
#2960864 - 03/03/09 12:09 PM
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John,
Am I correct in thinking that the scopes would be 90* off when you use the SBS saddle? If this is true, wouldn't your gotos be off by 90*? And how would you correct this.? It just looks to me that the scopes would not be pointing in the right direction, not north south like when you use a standard dovetail.
Dan
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: Blixx]
#2960886 - 03/03/09 12:15 PM
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John,
Am I correct in thinking that the scopes would be 90* off when you use the SBS saddle? If this is true, wouldn't your gotos be off by 90*? And how would you correct this.? It just looks to me that the scopes would not be pointing in the right direction, not north south like when you use a standard dovetail.
Dan
The mount has no way of telling what the initial position is. It presumes that you are beginning with the OTA pointing North, and does the first alignment star slew based on that presumption. If, for some reason, you begin with the OTA pointed some other direction then the first alignment star slew will be way off and will require substantial correction to center the alignment star. After you center the alignment stars, all will be well again. Goto operation is based on the alignment stars, not on any initial, pre-alignment position.
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Blixx
professor emeritus
Reged: 12/02/07
Loc: CO. Aurora, USA
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2960896 - 03/03/09 12:18 PM
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So once you go through the alignment stars the mount will know where you are and not care that the scopes were 90 out at he begining, is this correct?
Dan
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: Blixx]
#2960905 - 03/03/09 12:21 PM
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So once you go through the alignment stars the mount will know where you are and not care that the scopes were 90 out at he begining, is this correct?
Dan
Yes. There's no reason to begin with the OTA pointed sideways, though. Alignment will be quicker and easier if you begin with the OTA pointed North.
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Blixx
professor emeritus
Reged: 12/02/07
Loc: CO. Aurora, USA
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#2960918 - 03/03/09 12:25 PM
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I have not gotten the eq6-pro yet, so this may be a dumb question. Does the eq6-pro have index marks like the cg5asgt mount that I have now. So I gues my question is, even if it does have index marks, you line them up(even though the scopes will be 90 out) then go through the alignment as normal?
Dan
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: Blixx]
#2960929 - 03/03/09 12:30 PM
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Quote:
I have not gotten the eq6-pro yet, so this may be a dumb question. Does the eq6-pro have index marks like the cg5asgt mount that I have now. So I gues my question is, even if it does have index marks, you line them up(even though the scopes will be 90 out) then go through the alignment as normal?
Dan
Better to ignore the index marks and point the OTA North. Alignment will be quicker and easier. The mount, having no index switches, will never know that you are not using the index marks.
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donsinger1
sage
Reged: 10/28/07
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#3018036 - 04/01/09 01:41 PM
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So, if I understand you correctly, in using the side by side configuration, with my EM11 and Temma II Jr, I would have to tell a program like TheSky6 or Astromist that the DEC is offset by 90 degrees?
Thanks,
Don
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jrcrilly
Refractor wienie no more
Reged: 04/30/03
Loc: NE Ohio
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Re: Advantages of side by side setup?
[Re: donsinger1]
#3018164 - 04/01/09 02:35 PM
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So, if I understand you correctly, in using the side by side configuration, with my EM11 and Temma II Jr, I would have to tell a program like TheSky6 or Astromist that the DEC is offset by 90 degrees?
Nope. Neither the mount nor TheSky knows or cares that the DEC is offset; they just know where the telescope is pointed. Just align or synch as usual. Works fine with my Temma NJP and TheySky6 in sidebyside mode.
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donsinger1
sage
Reged: 10/28/07
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Re: Advantages of side by side setup?
[Re: jrcrilly]
#3018270 - 04/01/09 03:15 PM
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Great!
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