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Celestron VX and tandem bar

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#1 Night2Fire

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Posted 05 April 2013 - 11:17 PM

Is there anyone out there using the VX with the Tandem setup. I for the life of me can understand what I'm doing wrong. I have a bar set up with a 66MM and then a SSAG. I have date, Time and location set correct. I have in menu OTA west. When I move mount to both white marks the mount is pointing west. But every time I goto align I am no where near the ball park. This is the 1st night I'm getting to use the VX. Any suggestion or advice would be great.

Thanks in advance...

#2 Whichwayisnorth

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Posted 05 April 2013 - 11:21 PM

I need you to clarify. Define "tandem" as you are using it.

Also the first alignment star is not going to be close. Second will be closer(er) but still not that close. By the time you are on the second calibration star you should have them pretty close and by the time you are done with your 4th calibration star it should be really really close.

I digress, I need more info on how you are tandem.

Thanks

#3 Night2Fire

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Posted 05 April 2013 - 11:28 PM

I have a Dovetail with a 66 mm on one end and the SSAG with the 50mm on the other end. The 66 MM is more towards the middle for balancing issues. I just received the SSAG and mount last week and haven't figured out the best way to mount everything. I got a set of 76mm rings form Orion. I just don't see a way to really mount the 50 MM to the Orion rings real easy. I guess if I figure this out I can just use the mount the regular way.

#4 jrcrilly

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Posted 05 April 2013 - 11:33 PM

The first alignment star slew will be off by 90 degrees in dec because you are starting with dec rotated 90 degrees compared to where the mount thinks you are. Go ahead and slew in dec to get the first star centered. After centering the first alignment star that is fixed so alignment will be normal after that - and operation after alignment will be completely unaffected. The mount keeps track of the corrections required to center the first alignment star so eventually it will adjust to what you are doing and that first star will be closer.

#5 Whichwayisnorth

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Posted 06 April 2013 - 12:06 AM

So are you using a side by side saddle/dovetail? Any way you can post a photo? I would think that you just loosen the clutches, rotate it 90 degrees counter clockwise, tighten the clutches and align as usual. Or maybe I am still confused.

#6 jrcrilly

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Posted 06 April 2013 - 12:10 AM

Geez; I was thinking of the CGE, which has home switches. On that mount, there are no home switches. Just ignore the white marks and start with the telescopes aimed North. That's where the mount thinks they are aimed and it has no way of knowing that you ignored the marks so all will be normal.

You could still do as I described first and sooner or later it would figure it out and compensate - but you don't need to.

#7 cn register 5

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Posted 06 April 2013 - 02:44 AM

NO! NO! NO!

Your best option is to use the mount in the way that Celestron designed it to be used.

Fit the scopes to the tandem bar and fit the assembly to the mount.
Set the mount to the white alignment markers.
Set the OTA orientation to East or West, to match the way the OTAs are pointed. You have to do this before you start aligning, Press the Menu button when the scope is at the Press Enter to begin Aligning state just after power on.

Then do the alignment as usual. You should find that the stars ae reasonable close to where you are pointing but won't be perfect because the mount won't be perfectly polar aligned.

The second star should be much closer, the first Calibration star may also be out but the other should be close.

If it doesn't work like this do a factory reset.

Chris

#8 Night2Fire

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Posted 06 April 2013 - 07:45 AM

Hey Everyone,
Thanks for the info you all have been posting. When I said tandem I guess I should have said Side by Side.

Chris - That how I am Doing it. The way you said. Thats how i thought the book explained it. The 1st star seems to be way off. I even tried to do a factory reset to see if it gets closer. If I spin it 90 deg sow the scope is pointing north should be able to see Polaris almost dead center? Or is there a easier way to get it closer to polar align before I do my 1st alignment star?

#9 skyward_eyes

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Posted 06 April 2013 - 10:32 AM

This is very odd as I have used the VX in a tandem set up before and worked flawlessly. I did a simple alignment just as you would a regular alignment. The VX should not really care if it is set to its white mark points. You should be able to turn the mount on and do a simple alignment, it just happens to have the saddle side ways.

#10 rmollise

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Posted 06 April 2013 - 11:00 AM

Geez; I was thinking of the CGE, which has home switches. On that mount, there are no home switches. Just ignore the white marks and start with the telescopes aimed North. That's where the mount thinks they are aimed and it has no way of knowing that you ignored the marks so all will be normal.

You could still do as I described first and sooner or later it would figure it out and compensate - but you don't need to.


You can do that OR...the VX HC (and CG5) has a function that lets you tell it that when you are on the marks, the scope is pointing 90 degrees west...east...etc. ;)

#11 Night2Fire

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Posted 06 April 2013 - 01:12 PM

I'm going to give it another go tonight w/o the side by side and see if it works well this way. I went out and got some bolts so I can set it up on top of my 66mm. BTW - can you pot a polar scope on this mount? i never used a polar scope b4 so that's why I'm asking. I see a hole that runs threw the mount but see no info in manual.

#12 rmollise

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Posted 06 April 2013 - 03:01 PM

Why would you want a polar scope when the HC has the AllStar polar align procedure?

#13 Patrick

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Posted 06 April 2013 - 07:40 PM

NO! NO! NO!

Your best option is to use the mount in the way that Celestron designed it to be used.

Fit the scopes to the tandem bar and fit the assembly to the mount.
Set the mount to the white alignment markers.
Set the OTA orientation to East or West




I used a side by side setup for quite a while on several different CG5 mounts and a CGEM mount. I always pointed my scopes north as John C mentioned and ran my alignment from there with no issues. Even though Celestron has an East-West OTA orientation feature in the firmware I don't think it applies to the VX, CG-5, and CGEM mounts. It may be necessary for those mounts with motion limiters.

Patrick

#14 rmollise

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Posted 06 April 2013 - 11:53 PM


I used a side by side setup for quite a while on several different CG5 mounts and a CGEM mount. I always pointed my scopes north as John C mentioned and ran my alignment from there with no issues. Even though Celestron has an East-West OTA orientation feature in the firmware I don't think it applies to the VX, CG-5, and CGEM mounts. It may be necessary for those mounts with motion limiters.

Patrick


Nope. It most assuredly applies to those mounts. ;)

#15 Patrick

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Posted 07 April 2013 - 07:22 AM

Nope. It most assuredly applies to those mounts.



I'm not saying it doesn't work with those mounts. I'm saying it's an unnecessary step to go through to align those mounts. I've aligned my mount(s) hundreds of times with the white marks 90° off.

Patrick

#16 DaveJ

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Posted 07 April 2013 - 08:06 AM

Nope. It most assuredly applies to those mounts.



I'm not saying it doesn't work with those mounts. I'm saying it's an unnecessary step to go through to align those mounts. I've aligned my mount(s) hundreds of times with the white marks 90° off.


Exactly what I've encountered, as well. It's not the limit switches that's the problem on the CGE and CGE Pro, but rather the fact that they have homing switches that require the use of the "OTA Orientation" function to indicate east/west starting position. With the CGEM/CGEM DX/CG5/AVX I always just use the "scopes north" technique and don't mess with the OTA orientation settings regardless if I'm s-b-s or single OTA.

#17 Night2Fire

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Posted 07 April 2013 - 09:28 AM

Ok, So If I leave the mount on the normal north position, do I point the scope North or do I leave it facing east or west (west in my case) ? I assume I just point it north.

#18 DaveJ

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Posted 07 April 2013 - 12:21 PM

Ok, So If I leave the mount on the normal north position, do I point the scope North or do I leave it facing east or west (west in my case) ? I assume I just point it north.


Oh, man...I hate to tell you this, but "It depends." IF you've played with the "OTA Orientation" settings in the hand controller then point the OTAs which ever direction you've indicated. IF you haven't set the OTA Orientation, then point the OTAs north. This is why I don't mess with the OTA Orientation setting on the CG5/AVX/CGEM/CGEM DX. I just point the OTAs north and turn the mount on. :grin:

#19 Whichwayisnorth

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Posted 07 April 2013 - 12:48 PM

Ok, So If I leave the mount on the normal north position, do I point the scope North or do I leave it facing east or west (west in my case) ? I assume I just point it north.


Oh, man...I hate to tell you this, but "It depends." IF you've played with the "OTA Orientation" settings in the hand controller then point the OTAs which ever direction you've indicated. IF you haven't set the OTA Orientation, then point the OTAs north. This is why I don't mess with the OTA Orientation setting on the CG5/AVX/CGEM/CGEM DX. I just point the OTAs north and turn the mount on. :grin:


Exactly. That is what I suggested earlier. Forget the white alignment marks. Forget setting orientation in the hand controller. Just unlock the dec clutch, point the scopes north so they are lined up with the counter weight shaft too (both should be pointed north). Tighten the clutches and align as normal. If it helps you out put a sticker or something that lines up with the white line in that position so you can see it in the dark.






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