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View Full Version here: : ArgoNavis placement on a Big Dob


AstroJunk
03-10-2006, 08:03 PM
I’ve been asked about this a few times, so I thought I’d open a topic to see if anyone else has views/experience in the matter.

I recon:

When using a big Dob with just ArgoNavis, Mount it up top just where you need it to be. It is really good for fine tuning/locating objects by hand, and when you are cruising around a constellation, the object will never be too far away from the starting position so it’s quite possible to see a few targets with out moving the ladder – just by leaning over a bit (but not too far).

However, if you have ServoCAT (or plan to have it) it’s a different matter.
The ArgoNavis really should be mounted on a stalk for one main reason: The torque in ServoCAT is amazing. It slews a monster scope faster and more quietly than your Meade/Celestron would do. The system used in the 18” is exactly the same as used in the 30”. You (or worse, a guest) don’t want to be teetering up a ladder when you press the Goto button on a big slew in your direction ‘nuff said!!

What do you think?

I've put some before and after photos for consideration - the ServoCAT wireless handpad now lives where the AN did.

wavelandscott
03-10-2006, 09:41 PM
My opinion is that you are right in your thinking...I have an AN on a 12.5 inch Dob and I wish that the AN was mounted regularly near the focuser...

Unfortunately it is not (mine was all obtained second hand)...I do have cables long enough to let me hold the AN and hand drive but mounting it near the focuser would be better (I think). Alas, to change now would mean adding some counterweights and removing a nice brass holder...

I don't have a Servocat so can't comment on slew speed etc. I enjoy the AN a great deal by itself so I bet that the combo (AN and Servocat) would be killer...

Rodstar
03-10-2006, 09:50 PM
I have decided to place my Argo Navis next to the EP too. I tend to work the same area of sky as much as possible during a night's observing session, and I would rather avoid getting up and down the ladder as much as possible.

Sounds like with Servo-cat however, caution dictates the set-up you now have, Jonathan. Maybe I'll never get servo-cat??!

Peter Read is having a think for me about how he might organise the cabling to avoid lots of messy loose cables running down to the LTA.

AstroJunk
03-10-2006, 10:09 PM
You've got it right Rod - plan for now! you can always move the thing when you succumb to the joys of ServoCAT later.

Tick, Tock, Tick, Tock ... (sorry, wrong thread :lol: )

JimmyH155
05-10-2006, 04:40 PM
I have only recently installed AN on my 12" Lightbridge. The cables that came with the AN were far too short for me to use standing up. I sent Gary of Wildcard Innovations an email and he very kindly sent me a longer set of cables. Thanks Gary
I then tried to mount the control box holder on the top knob that holds the secondary mirror can in place (loop of wire). Splendid when the scope was pointing directly up, but hopeless when I moved the scope down about 20 degrees- the scope kept going:lol:
I have ended up making a simple stand with one leg and a piece of ply nailed to the top and bottom of the 3" x 3" leg. Very stable. I then made up an inclined holder for the controller, so all I do is place the "stand" close to the scope, put holder on top and then I can easily read the screen when standing at the EP. Only danger to watch out for is dont move the scope too far without also moving the stand and be careful of how long the cables will stretch. Don't trip over them like I did the first time. I think a few sessions and the procedure to adopt will become second nature:D Hanging the controller off the top of the scope - on the 12" anyway - would only work if you put a large counterweight on the botton (Loudspraker magnet ??) That's more stuff dangling off the scope!:)

gary
05-10-2006, 10:47 PM
Hi and thanks for the post.

Mounting Argo Navis on the top-end of large Dobs is a popular choice,
particularly for scopes of between 15" to 20". See here. (http://www.wildcard-innovations.com.au/images/hector3.jpg)

For units with the original-style enclosure, Velcro self-adhesive tabs or
an acrylic holder (http://www.obsessiontelescopes.com/accessories/ArgoNavis/Argo_holster.jpg) are both popular choices.

Units in the new-style enclosure come with a mounting cradle (http://www.wildcard-innovations.com.au/argo_describe.html) that is designed
to be mounted in a variety of ways including with wood screws, thumb-screws
and brass inserts, Velcro self-adhesive tabs and Velcro OneWrap straps.

For smaller aperture Dobs (e.g. 8" to 15") and very large aperture Dobs,
(25", 30"+) many mount the unit either on the side of the rocker or
on a stalk. For example as seen here (http://www.wildcard-innovations.com.au/images/mann_obsession15_1.jpg) and here (http://www.wildcard-innovations.com.au/images/scheirman1.jpg).

Markless Astronomics in North Carolina manufacture a stalk (http://www.marklessastronomics.com/#dscstalk) for use with the
Argo Navis which is a popular choice.

I've routinely used an Argo Navis mounted near the eyepiece of a 20"
and this location is very convenient for the reasons you cited.

Thanks again for the post.

Best Regards

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au

wavelandscott
05-10-2006, 11:54 PM
Gary,

Thanks for those links...lots of good ideas on one page :thumbsup:

JimmyH155
24-10-2006, 02:52 PM
Yes forget my previous post. As Gary from Wildcard Innovations says, a stalk is the way to go. I just used a 2 inch x 1 inch piece of pine from Bunnings, about 700mm long, two 6mm bolts through the bottom box (to right of the supplied EP bracket) :D and screwed up with wing nuts so no tools. on the top of the stalk I put a little 4 inch x 4 inch piece of ply,- angled a bit to suit my eyes, and screwed the Argo Navis controller bracket to that. Two coats of white gloss and it fits in with the white of the LB. Now I can move the scope from vertical to horizontal and it wont touch the stalk, and no wires to get in the way. :D :)

gary
24-10-2006, 09:51 PM
Hi JimmyH155,

Congratulations!

Great to hear about your stalk and from the description the total solution
sounds very economical.

Best Regards

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au

wavelandscott
25-10-2006, 10:07 AM
After looking through some of Gary's links, I too put together a "Bunnings Stalk" out of pine...I've not had a chance to try it out yet "in the field" but at home it seems to work well.

I used velcro to affix it to the scope...just need to prove it works and then a little paint and viola...so far so good!

gary
25-10-2006, 10:39 PM
Hi wavelandscott,

Great to hear of another DIY stalk. Once you give it a paint, we'd love to see some
pictures.

Best Regards

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au