StarStuff side by side bar etc.

[avandonk]

I have various imaging optics and all suffered from the same thing, it was a pain to change from one setup to the other. I have lashed out and bought the side by side bar etc from StarStuff

Here
http://www.starstuff.com.au/index.html

What this all means now everything is a 'module' and can be easily swapped and added as need be. Here is some images of the 300mm Canon lens imaging setup.

The black lens is a 16 to 180mm F1.8 zoom and I can just see the Helix nebula in real time through it with the Gstar on the computer screen. Obviously most other nebs are easier than this. The 100ED in this configuration is the guidescope.
What is even better the center of gravity is closer to the RA axis so there are less weights on the counterbalance shaft. Dynamic balance can now be far more easily obtained. Whats even better it is far easier now with or without the fridge to get very good dynamic balance.
I will show the other combinations when the weather cools down. When it is 38C it is not good for me or the optics to be outside.
The whole assembly is far solider than the 100ED mounted on top of the 150mm achro and uses far less counterweights. when in this mode.

Bert

[avandonk]

Here is what it looks like with a Meade SN 10" and using the 100ED as a guidescope. Again with the zoom lens as a finder. I took images all last night and could not see any evidence of flexure between the 100ED and SN 10". There was northerly gusts every now and then overnight. this did not seem to affect the stabilty of the mount. The EQ6 did not have any trouble with this load.

There are a couple of images taken with the Meade SN 10"

Bert

[skwinty (Steve)]

Hi Bert
How many counterweights do have on the setup and how much would you estimate is the weight of all the scopes, camera etc.?
Also, how well (ie duration) did your eq6 track unguided?

[avandonk]

The mount has five counterweights in this configuration. Three large (5.4kg) and two smaller (4kg?). The total load of the scopes and hardware above the mount would be close to 26kg (60lbs). If the polar alignment is good a minute without guiding is as good or almost as good as guided.

As youcan see this mount has no gearboxes it has instead belt drives. This eliminates 'microjumps' due to the usual gearboxes. It also has no backlash.
If I set a tiny amount of backlash compensation in the guiding program the autoguiding just oscillates.

The good thing about the side by side is it that lowers the center of gravity of the load toward the RA axis.

This is about as much as the mount could handle. If it is well balanced should not give me any problems.

Bert

[peter_4059 (Peter)]

Bert,

I notice you have replaced the grub screws that fix the Starstuff bar to the EQ6 with bolts. Do you know what diameter/thread you used? Did you drill out/tap the holes to a larger diameter or stay with what the mount already had?

I'm looking at getting the same Starstuff bar arrangement.

Cheers,

Peter

[avandonk]

Peter the grubscrews in mine were 6mm so I just simply replaced with 6mm cap screws. Standard is 4mm I think.

Just weighed all the bits with bathroom scales.

100ED assy 7.0 kg
150mm assy 10.5 kg
300mm assy 6.5 kg
10SN assy 17.0 kg

The 100ED and 150mm achro weigh more as they both have a 2.7" Astro Physics focuser which are quite heavy and very solid.

Finder assy 6.0 kg
Fridge assy 2.0 kg

So 10SN + 100Ed + finder is 30 kg or 68 lbs the Canon would add more and the main bar of the side by side is about 2.0 kg. So the EQ6 is doing quite well to hold and autoguide this little lot.

The 300mm set up is about 21.5 kg or 48 lbs
The 150mm and 100ED etc is 25.5 kg or 57 lbs.

I think I should carefully balance from now on. Although this is relatively straightfoward with this side by side.

Bert

[peter_4059 (Peter)]

Cheers Bert,

My SBS bar arrived Thursday - Got to use it for the first time last night and all went well.

It's good to hear someone else is giving the EQ6 a good workout. I'm now up to 20 kgs of counterweights.

Peter