Breeze and scope size / length

[brantuk]

Plus one for ADM - I change all my dovetails and saddles for ADM as a matter of course now - gave up on SW ones a long time ago cos they're just too flimsy.

[Stu]

5 hours ago, CraigT82 said:

I'l give you a reason - future proofing.  Can be kept and used for bigger, future scopes.

But I'm perfectly happy with my scope and won't be selling it. For a lightweight grab and go a Losmandy is overkill and just adds weight.

I really struggle to believe that an ADM Dovetail milled out of solid aluminium will flex with a scope like an ED100, if used with some decent CNC rings with a flat face that clamps onto the flat face of the Dovetail. You may well get flex in other areas, perhaps in the tube itself or even from the lining of the rings (felt or cork or whatever). It is tricky to get rid of all of it.

[Alien_Photons]

The rail rings and scope tube will act to stiffen each other as a whole. My 100mm f7.5 refractor has a three second dampning time on my mount. My 80ED f7 has a one second dampning time on the same mount even though its heavier. Vibrations can be changed or removed by stffining or changing the geometry.

Start with the legs.

[Stu]

7 minutes ago, Alien_Photons said:

Start with the legs.

Too true. Most important bit of all is a steady tripod.

[CraigT82]

2 hours ago, Stu said:

But I'm perfectly happy with my scope and won't be selling it. For a lightweight grab and go a Losmandy is overkill and just adds weight.

Might be a crossed wire here somewhere.

I wasn't suggesting a losmandy dovetail for your grab and go setup... I was suggesting it for the OP. You said you couldn't think of any reason to swap to a losmandy dovetail so I suggested one:  Futureproofing.

My thinking is if Alan already has a sturdy tripod and mount, and is thinking of upgrading his dovetail, then going for a losmandy one could be a good idea.

I applied that logic when I bought a new tripod. I was considering a berlebach uni but ended up getting a planet and couldn't be happier with it.  Granted it's overkill but when I come to upgrade I know the tripod is good for whatever I can throw on it.

No harm in overmounting!  

[Alien_Photons]

Just another idea is adding a flat ali plate across the top of the rings. I had one on my vixen rings years ago to mount a small guide scope. When the little scope went I kept the bar more for a handle than anything. But had I convinced my self it helped.

My money is on those little screws used to lock the leg extensions in those plastic rings half way up the legs. I cant remember when I stopped using this tubular legs and made some big hefty wooden legs. But for the record I cant remember last week either.

[Alan White]

Firstly, again thanks for the input, but Guys please, STOP about the tripod and mount.

Its on 2" steel CG5 Tripod, Giro Ercole Head!!!    The mount is solid and damps out <1second, it's fine.

 

THE PROBLEM is in a breeze and the optical tube at higher magnification, I am mainly planetary and lunar observing at present.

 

If I mounted the scope on a 12" 20 foot deep pier the tube would still do what it's doing at certain times I am sure.

The tube need better rigidity, probably 3 rings and a decent dovetail I think.

 

I love SGL in the wholesome debate and multiple differing answers, provides plenty of food for thought.

 

[SonnyE]

I'm still putting my bet on the change of diet...

Say maybe try Mediterranean? South of France?

Or come try some of Sonny's Interstate Famous Road Kill Bar-B-Que!

Half a world away should relieve that wind.

You need a block wall like I have. I hunker down behind it and the wind can blow its brains out, but it can't touch dis. And my little 80 mm sez, "Hah!"

Like they say in Real Estate, it's Location, location, location.....

See, I didn't say a damned thing about your mount...

[Alan White]

12 hours ago, SonnyE said:

I'm still putting my bet on the change of diet...

Say maybe try Mediterranean? South of France?

Or come try some of Sonny's Interstate Famous Road Kill Bar-B-Que!

Half a world away should relieve that wind.

You need a block wall like I have. I hunker down behind it and the wind can blow its brains out, but it can't touch dis. And my little 80 mm sez, "Hah!"

Like they say in Real Estate, it's Location, location, location.....

See, I didn't say a damned thing about your mount...

Sonny E 

No mention of the mount gets top marks.

BBQ sounds good too.

I think we are on the same page in that I need some shelter to break the wind.

 

[Bukko]

Hello, Alan,

I have a spare 13" Vixen (Skywatcher) dovetail bar you are welcome to try, just to rule this out...

 

Just let me know.

Gordon.

[SonnyE]

14 hours ago, Alan White said:

Sonny E 

No mention of the mount gets top marks.

BBQ sounds good too.

I think we are on the same page in that I need some shelter to break the wind.

 

I would agree whole kindheartedly. Might be a good time to consider some form of an Observatory or Astronomy shed? (Well anchored I would add.)

But not too tight. You still need ventilation for any occasional foul wind that occurs.

[Dave In Vermont]

You can also hang a weight on a thin cord from close to the center of the tripod. I use a 10-pound weight from some barbells (any other type of weight can be substituted) on a 15-inch piece of twine from the center-bolt of an AZ-4 - loopingover the accessory-tray in the middle of the tripod. Although it seems counter-intuitive to do so, the hanging weight causes the mount to dampen-out vibration in wind, and other causes vibrations.

It works great! Even if the combined weight surpasses the stated weight-limit of the mount & tripod.

Dave