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Off Centre Mount

Started by MarkS, May 14, 2013, 20:11:11

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MarkS


More planning for my observatory.

If I cast a 12" diameter concrete pier, is there any reason why the mount shouldn't sit off-centre as in the photo below (the 12" cardboard disk represents the top of the pier.

By doing it this way, the scope could access far more of the sky before hitting the top of the pier.


Carole

Looking through the polarscope might be difficult - looking at your picture, looks like the pier might be just where your chin needs to go.  I had this problem with my CG5 GT and I could never do a decent PA because of this reason.

Carole

Rocket Pooch


MarkS

Thanks Chris.

Carole - if I ever to need to use the polarscope (unlikely) I'll just use a small mirror.  

So I plan to bolt one of these:
http://www.altairastro.com/product.php?productid=16169  (25 quid from an odds and ends bucket at Kelling Heath)
to one of these (300mm diameter)
http://www.ebay.co.uk/itm/Mild-Steel-Plate-Profiled-Disc-10mm-Thk-Various-Diameters-/221214751172#ht_326wt_988
then attach the EQ6 using the centre bolt and then bolt the whole lot down onto thick studs protruding from the concrete pier.

If I change my mount I just need to redrill another 10mm mild steel plate.

Mark

Carole

You were lucky with the pier plate Mark.

Re: Polarscope, I tried to use a mirror but found it impossible.  Made an adapter to use a webcam on the polarscope, but that wasn't very successful because it didn't sit quite Square add to that an unlit reticle it was a nightmare until I got the NEQ6 which sticks out further.

Carole


Mike

There are many pieces of software available to do polar alignment without the polar scope at all. I use alignmaster.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

RobertM

I wouldn't worry about the polar scope because of what Mike mentioned.

An even better idea would even better would be something like this: http://www.astrosysteme.at/eng/mount_ddm160.html

julian

Here's is my setup, which works ok.






Julian

MarkS

Thanks Julian - interesting to see.

What is the diameter of your pier?

Did you do the metal fabrication yourself - or an engineering shop?

Quote from: RobertM
An even better idea would even better would be something like this: http://www.astrosysteme.at/eng/mount_ddm160.html

Nice!

Mark

julian


MarkS

Wow - detailed measurments of everything!

I can see the owls nest.  Can't see the robins nest!

julian

QuoteI can see the owls nest.  Can't see the robins nest!

give it time

Ivor

I'm in discussion about putting a pier in the garden so I'm following this thread with interest. With the cost of the Astair pier adapter I'm keen to see any alternative.

Julian you didn't answer Mark's question about your setup and I'd be interested in knowing

QuoteDid you do the metal fabrication yourself - or an engineering shop?

MarkS

Quote from: julian
Owls nest made by Astro part  01908586747

I think the quote above was Julian's answer.

The Thing

Quote from: Mike on May 14, 2013, 22:50:21
There are many pieces of software available to do polar alignment without the polar scope at all. I use alignmaster.

I use AstroTortilla.