Mounting an Argo Navis - Truss dob users

[CoombellKid]

Just really getting peoples thoughts on mounting an Argo Navis on a stalk
or up on the secondary cage. What are the drawbacks of either approach?

I'm getting the impression that up on the secondary cage isn't always very
user friendly, meaning it isn't always located in best position. The only thing
really worrying me about the stalk approach is me running into it or bumping it
in the dark.

regards,CS

[madtuna]

there's not much weight in the argo hand unit so it shouldn't affect balance, have you concidered velcro strips located at random spots on the secondary cage?

I know it's not a dob, but on my G11 I have velcro strips at random places, so no matter where I poke in the dark it will stay somewhere and is in easy reach no matter where I am.

[gbeal]

My Argo was mounted on a stalk (Gary sells or sends a bracket that is easily mounted on the stalk), and the stalk attached to the rocker box, so the Argo always ended up in a similar place. This was for my homebrew 10 dob, housed in a sonotube.
The latest scope is the 16" truss dob, and for some weird reason I have it on the secondary cage, next to the finder and eyepiece, middle of them actually.
There is good and bad for either. Weight (contrary to what Steve says) to me was the issue, but I am sorely tempted to try it from the rocker box again, as the less weight I have "up there" the better.
Gary

[CoombellKid]

Gary,

My initial thoughts were it would be more convenient to have it up on the
SC and power it from the dew controller. But the more I think about it, it
seems no matter where you mount it on the SC there will always be a possy
where it isn't so convenient. Where as a stalk you can have it pretty much
follow you... yup the more I think about it a stalk is the way to go. besides
I have heaps of 16mm ali tube and the AN came with a holster/holder I can
easily a wooden bracket to mount the holder to the ali...

madtuna, thanks for your input with the velcro dots... it was worth
considering.

regards,CS

[CoombellKid]

The only other thing worth considering is I guess the stalk needs to be
located towards the back of the rockerbox (I'm building a 16" too) so
it doesn't get in the way when your close to the zenith.

regards,CS

[Starkler]

Mine sits up on the UTA but the scope was designed to balance that way, meaning it has to be there or I have balance issues.

The cradle is mounted on a stiff hinge which allows it to be angled and the argo is powered from the spare port on the dew controller.
I find it a very convenient place to have it and wouldn't have it any other way.

[tnott]

I have mine mounted on a truss pole, because I didn't have room for a stalk. Because it is lower down it does not affect balance.

A friend of mine has an 18 inch SDM with it on a stalk - it does not get in the road at all and works really well. Both these scopes have servocat as well so we do not use the Argo unit for guiding to a target.

I would imagine that having it near the eyepiece in such a case would be better. You just need to add it to your calculations when designing the scope, as it is a significant weight.

[Darkplague]

Heres mine on a stalk, always easy to read and use, never had any problems.

[CoombellKid]

Thanks guys

All options have their benifits, but I think the stalk is the most practical.
However if I were to mount it on the SC I'd do it like Geoff's SDM. Maybe
I can incorporate both...

regards,CS

[CoombellKid]

Geoff,

With the AN in that possy, does the AN's LCD panel ever interfere with
your view into the ep?

regards,CS

[Starkler]

Nope, not at all :)

[wavelandscott]

Mine is stalk mounted similar to Darkplauge's.

I got my stalk from SDM Telescopes...he had an extra and was willing to sell it to me. Works a treat.

I previously tried the secondary cage with velcro and also on a truss pole. I also spent a long time just holding it next to the eyepiece...weight was a bit of an issue for me on the secondary cage and on the truss pole and hand held I always felt like I was dragging along too much cable and was afraid I'd trip in the dark.

My scope is 12.5 inches and since I stay stanidng on the ground all of the time the stalk works like a champ. If I was going to be a ladder person I'd consider the secondary cage and balance it that way from the start.

Good Luck!

[Starkler]

If looking for a list of pro and cons to UTA mounting it might look something like this:

Pros:

Convenience - argo unit is close to the eyepiece so your attention can stay always at the business end.
Lack of stalk is one less thing to set up (or get broken).


Cons:

The argo's weight becomes an integrated part of the scope that must be designed in and cannot be separated. Need for higher mounted alt bearings to balance.
Possible extra wiring complexity if power is otherwise not required at the UTA. Dew control is a good reason to run power there in any case.

[ausastronomer]

Hi Rob,

I have tried it both ways on my 18" Obsession. I had it mounted at the top of the scope when I first got it, then I got a catstalk from Peter Read in late 2006. I have also spent a good bit of time using Andrew Murrell's 20"/F5 truss scope, where it is also mounted on the UCA.

Without question I much prefer to have it mounted on the stalk. I just find for my own observing style and preference it is much easier to use and more convenient.

Cheers,
John B

[AstroJunk]

In general terms I found the AN on the UTA much nicer for manual visual work.

However: For driven dobs - If you need a ladder, it should be on a stalk. If you don't, you can keep it on the UTA. It's all about what happens when you press the goto button and you are still teetering up a ladder in the dark!!

'The Horsehead was clear tonight, I think I'll go check out the Leo triplet ...'

[CoombellKid]

Which is why I'm inquiring now as I'm building the SC at present and need
to know if... well make a choice. The extra wiring is no problem I have all
the components to send power up the UTA and my TO dew controller will
be hard wired into the SC just like yours.

Thanks for the input guys, to tell you the truth I kinda like both ways.
I could build it in and make a UTA AN coutner weight, for when I have the
AN stalk mounted.

regards,CS

[AstroJunk]

My advice is make it bottom heavy.

You will need fewer counterweights at the top end to accomodate all of the fun stuff you will eventually put up there!

bino-viewer, video camera, dslr, photometer, the worlds largest eyepiece, etc etc ...