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Tripod orientation, single leg north side or south side?

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#1 f300v10

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Posted 25 June 2019 - 04:48 PM

I've always used my EQ6-R oriented the way it shipped, which is with the single leg pointing south, and counterweights between the others.  I use two fairly heavy scopes to image with, an MN190 and a C11, both of which require a good bit of counterweight.  With the weights on but the scope off, the mount is much to easy to tip over if pushed toward the north for my liking. 

 

The angle adjustment post on the tripod can be moved to the opposite side, thus turning the tripod 180 degrees.  Doing so would greatly reduce the chance of the mount tipping when mounting the scope as the counterweights would be over the north leg, and at my latitude the weights will clear the leg no problem.  This change would also give the long tube of the MN190 much more clearance to the tripod leg when imaging near the meridian.  Easier access to the polar scope would also be a plus.  

 

So my question to the group is there a downside I'm missing in having the single leg to the north?

 



#2 bobito

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Posted 25 June 2019 - 04:55 PM

I can't imagine why it would make a difference if clearance isn't an issue. 



#3 Dynan

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Posted 25 June 2019 - 04:56 PM

Northern Hemisphere - single leg pointing North

Southern Hemisphere - single leg pointing South

 

Edit: Example: https://www.celestro...zed-telescopes#


Edited by Dynan, 25 June 2019 - 04:58 PM.

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#4 petert913

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Posted 25 June 2019 - 05:04 PM

Northern Hemisphere - single leg pointing North

Southern Hemisphere - single leg pointing South

 

I always felt this orientation was best for two reasons:

 

1.  Helps me point the mount towards the Pole.

2.  On traditional GEM's  (not CGEM)  there is considerably more weight toward the front of the

tripod.   Polar facing leg helps support the offset load.



#5 Eddie_42

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Posted 25 June 2019 - 05:10 PM

I switched my EQ6-R pro to be north for the single leg, just for the ease of accessing the polar scope. 

 

Just speaking to the physics of it all....So long as your center of mass for the whole rig is within the triangle formed by the legs, you are fine. Thats the purpose of a tripod, stability.  The closer the center of mass gets to the edge, the less stability you have, you also have a long lever-arm wtih the tripod legs, so a small force (push) is amplified compared to a shorter tripod.  With the north leg, you are tipping NE or NW, not a chance you are going up and over the leg directly.  With the south leg,  the geometry between the two northern legs is the limit, and is likely a touch closer to the CoM. 

 

When dismatling or assembling, maybe do a peice-wise approach, half the weight -> scope -> other half? The clutch and clamp are plenty to hold while you configure the assembly. 


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#6 kathyastro

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Posted 25 June 2019 - 05:12 PM

Since the azimuth post on your tripod is moveable, set it up whichever way you want.  For mounts with a fixed azimuth post, the post is typically over the single leg, so the single leg points towards the pole.



#7 Garyth64

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Posted 25 June 2019 - 07:02 PM

I have heard both arguments over the years, and except for clearance  I don't think it matters.  Even if the CW is over one of the legs, the center of gravity is approximately over the tripod or pedestal.

 

For example:  My old CG5 mount has the tripod leg pointing south

 

tripod north.jpg

 

The pedestal leg on my Meade RG mount points south.

 

The tripod leg on my CGEM II mount also points south.

 

Just put it where you want it, if it doesn't work for you, switch it. smile.gif



#8 johnsoda

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Posted 25 June 2019 - 07:29 PM

On my CEM60EC with tripod, it can make a big difference with my long refractor. If I plan to image in the south, I put the single leg in the north, and vice versa. My camera can definitely hit one of the legs if I’m not careful. For my short refractors and my SCT, it doesn’t really matter.  I usually put the single leg in the north, if clearance isn’t an issue. 



#9 AhBok

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Posted 25 June 2019 - 09:17 PM

I prefer 1 leg north (northern hemisphere) for a practical reason. I make my own telescope dollies with my scopes permanently set up. They are made in a T shape with 2 wheels on the south side and 1 wheel pointed north. I can easily access my PAS by doing it this way.



#10 CharlesW

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Posted 25 June 2019 - 09:28 PM

It’s not a tremendous amount of weight but I have run 90lbs of counterweight on a tripod. Trust me when I say, for economics sake, you want the single leg pointing north. Despite the “triangle” that was mentioned earlier, the fact of the matter is, a single leg pointed north supports the weight of the counterweight shaft beyond the triangle and keeps it from tipping forward if you have an unforeseen event. I know this from personal experience when I almost dumped my MX while loading my C14 onto it because I had two legs forward. I’m running 120lbs on a pier now and have been as heavy as 180, but even if it was only 20lbs, I would still operate single leg north on a tripod. 


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#11 f300v10

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Posted 26 June 2019 - 09:09 AM

Thanks for all the replies folks, I will be switching to single leg north.



#12 Garyth64

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Posted 26 June 2019 - 12:50 PM

Thanks for all the replies folks, I will be switching to single leg north.

Ok, I'm sure it will be ok.

 

On my mounts, I have the single leg south, as I mentioned.

 

Here is a shot of my Edmund mount with the leg pointed south.  When the  telescope is swung to view an object in the south,  the CW is over one of the legs.  Looks very stable to me.

cw over leg.jpg

 

Here was my 10" f/7 newt on a homemade mount with lots of heavy CWs. The leg is pointed south.  For viewing, the CWs are over one of the other legs.  Also, very stable.  There's  no danger of this tipping over.

10 2nd light 2.jpg

 

One more.  On this tripod I rotated the mount so the leg would point north.  I swung the scope and you can see that the CW is out over and between two of the legs.  Being a small mount, I can get away with it.  If it were larger and heavier, I would be concerned that if bumped hard, it could time over.

cw over two legs.jpg

 

You'll just have to determine which is best for you.  I try to have all my mounts with the leg pointing south.smile.gif


Edited by Garyth64, 26 June 2019 - 12:53 PM.



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