Mounting two scopes on a Celestron AVX

[Luter68]

Hello, 

I am thinking of buying a side-by-side mount like this one

https://www.teleskop-express.de/shop/product_info.php/info/p223_Starway-VC4-side-by-side-mount-for-two-telescopes---cameras.html

to mount two scopes in my Calestron AVX. The idea is to have a small newtonian (130 or 150 pds) on one side and a bar with a camera with a 200 mm lens on the other (currently the camera is attached at the end of the counterweight shat but so far I am not satisfied with what I get as results). Thus, I am looking for different solutions (like the side by side mounting).

However, on the mount, when the white marks on the declination axis are aligned (as requested at the start of the two star alignment procedure), the slot on the mounting saddle is aligned along the polar finder direction. Thus, if I use the VC4 at alignment stat the mounted tubes would be pointed at a 90 degree angle.

The question is, can I start the two star alignment with the index not aligned (that is, with the slot in the mount turned 90 degrees with respect to the position where the reference marks are aligned) without losing accuracy in the star alignment? Since nights of clear sky are damm rare, I would like to find out if anyone knows about before spending a valuable night testing around (and spending the 129 Euro for the rig).

Thanks a lot!

[LunaSwift]

This is an extract from the AVX manual, 

I think this is what you require

oTa orientation – Some users may wish to use an optional tandem bar adapter which allows you to attach two optical tubes to the mount at the same time When most tandem bars are attached to a mount, the optical tubes are positioned at a 90° angle from the standard con guration In order for the mount to be successfully aligned with the stars, it must know that a tandem bar is being used and in which direction the optical tube(s) are positioned (East or West) when beginning an alignment The tandem option must be set before beginning any of the initial star alignments To set this option, go to the Scope Setup menu, select the Tandem option and press ENTER Then select from one of the

following options:

• east – If the attached optical tubes are facing towards the east when the declination index makers are align, select East

• West – If the attached optical tubes are facing towards the west when the declination index makers are align, select West

• normal – If the tandem bar is no longer being used, select “normal” to turn off this feature

Meridian – This feature instructs the mount on how to

respond when it is slewing to objects that are accessible from both sides of the Meridian The Meridian feature allows the telescope tube to remain on a desired side of the mount when slewing, and continue to track according to the R A slew limits the user has set. See R.A. Limits below. The Meridian feature allows for four choices:

• Favor current – Allows the mount to favor whatever side of the mount that it is currently on when slewing to objects close to the Meridian For example, if your R A slew limits are set to allow the mount to track 10° past the meridian, then the telescope will continue to stay on its current side of the Meridian when slewing to objects that are as far as 10° beyond your Meridian

• Favor West – If the target object is accessible from both sides of the mount, selecting “Favor West” instructs the mount to point to the object as if it were on the west side of the meridian The optical tube will then be positioned on the east side of the mount and pointing west

• Favor east – If the target object is accessible from both sides of the mount, selecting “Favor East” instructs the mount to point to the object as if it were on the east side of the meridian The optical tube will then be positioned on the west side of the mount and pointing east 

[Beeko]

The avx will struggle with a 150pds by itself let alone side by side mounting. 

[Luter68]

Thanks a lot LunaSwift, indeed it is exactly the information I need.

I read the manual long ago but I didn't notice it at that time and didn't check it again........

Have a nice evening.

[Luter68]

53 minutes ago, Beeko said:

The avx will struggle with a 150pds by itself let alone side by side mounting. 

The idea, when using such an arrangement, woiuld be to use the 200 mm for photography and the 130 or 150 for visual.

At the moment the camera with the 200mm  is mounted at the end of the counterweight bar, but I am not very satisfied with the results. Still not fully understanding where the problem is. Besides that, I find the location unconfortable (the camera is always upside down).

would I decide trying photography with a 150 or 130, then I would mount it solo and use an off-axis guide.