Mounting scope on scope

[lazjen]

I've got a GSO RC10 mounted on my G11. I have just bought the SharpStar 107PH (http://www.iceinspace.com.au/forum/showthread.php?t=147620).

I'd like to have both mounted at the same time, ideally in a manner that I can take the SharpStar off for travelling and to allow the Coronado to go back onto the RC10 for daytime use.

The rings and mount bar on the SharpStar are I think the V type?, as I can mount it direct to the G11. The top of the RC10 has a Losmandy dovetail on it
(http://www.teleskop-express.de/shop/Bilder/shop/ts-ritchey-chretien/rc-10-inch-carbon-1000.jpg).

My thoughts are to get something like this: http://www.admaccessories.com/Miscellaneous_DV-SAD.htm? to join the two scopes. Would this work? Or is there a better way?

P.S. I'm aware I'm getting closer to the weight limits of the mount. :)

[blink138]

hi chris, what is the reason you want them on the mount at the same time?
i have a very similar setup..... c11, apm 107 and a g11 but i take off which ever i am not using and rebalance and it is very easy this way
pat

[lazjen]

It is mostly a convenience factor (some people might term it laziness :p ).

However, I'd like to set up one of my cameras on the RC10 and another on the SharpStar. I don't want to have to pull it all apart each time I want to swap over. I also don't really want to be lifting and moving the RC10 around a lot.

I admit it's very unlikely I'll be using both at exactly the same time, but I could see it being possible to use both within the same night.

[blink138]

perhaps consider a side by side then chris?
if it is iffy weight wise a side by side would be a better option as both scopes are closer to the swivel point i think
pat

[lazjen]

I am not sure if I'd be opening up more issues going side by side with balance and maybe flexing?

For now, I'm going to do as you're doing: swap scopes around. I'll try that out for a while and see what pain points I get.

[doppler]

Side by side works for me. I screwed a vixen dovetail bar to a length of 60mm x 10mm aluminum bar and a saddle on each end. It is easy to balance by sliding each scope forward or back and the bar left or right. Much easier than a top mounted second scope. Here's my setup with a 6" RC and 102mm f7 achro finder scope on a HEQ5 mount.

[lazjen]

What's the weight of each scope? I'm going to have a 10 kg difference between my 2 scopes. I suppose it's still just a matter of finding the centre point (probably with a 2:1 ratio in my case). It would need to be a wide plate to fit them side by side.

[doppler]

Not sure of the weights but the 6" RC is a lot heavier than the 4" refractor. There is plenty of movement in all directions to tweak the balance with each scope and accessories. I can fit my 180mm mac cass on this mount instead of the RC (with an extra counterweight) but that is pushing the mounts capacity a bit. You can buy purpose made side by side plates but my diy was a lot cheaper.

[lazjen]

Something like this: http://www.bintel.com.au/Accessories/Dovetail-Plates---Adapters/Losmandy-DVSBS-Plate/1083/productview.aspx I guess. I'll have to do some measurements/calculations to see if that would work or if I need to get something larger.

[doppler]

My setup has 300mm centre to centre which has plenty of room to spare, so that bintel one at 250mm should be ok. You should try and search the threads for side by side mounts there would be a few people with that set up here.

[lazjen]

Yes, I think you're right, it should work fine.

I did a brief search and read a few threads - one mentioned using the setup with a dome, so that was useful info for me. Thanks.

[beren]

I have used side by side configurations with some of my gear but always end up going back to the bottom/top way because I found it easier to balance. ADM have two products called the max guider and mini max guider which permit movement up/sideways and work with losmandy style plates. I have a max guider and I really like it , handles the small refractors that I piggyback on my sct. Maybe worth checking

[lazjen]

@beren: When you used side-by-side, did you change your gear around often?

Your suggestion is what I had in mind when I first created this thread. I'll look into it.

For my purposes, it will be the same gear all the time - the only change will be putting the solar scope on instead of the refractor. And when it's on, I'm not too concerned with the balance being out a bit, so I hopefully won't need to adjust things too often.