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Thoughts on evaluating tripods ?

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#1 SteveInNZ

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Posted 18 September 2012 - 03:17 PM

I want to compare some lightweight tripods/arrangements/mods and am looking for suggestions of reasonably simple tests to compare them. Any thoughts ?
Other than wind loading, when is a tripod at its worst ?

Steve.

#2 Midnight Dan

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Posted 18 September 2012 - 06:20 PM

A tripod is at its worst when the legs are fully extended, and when you have a long, heavy load like a long refractor.

-Dan

#3 SteveG

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Posted 19 September 2012 - 12:23 PM

One of the things that stands out to me is the tripod leg to hub connection. Take note of the most expensive, solid tripods in the market, you will see that the spacing between the leg halves or tubes is always very large. Surveyors tripods and the super lightweight Rob Miller tripods are made like this.

#4 Footbag

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Posted 19 September 2012 - 01:15 PM

Wind load is a must, but I wonder how you would test it?

It would also be nice if you could test vibration dampening. If a wire falls or a bug bumps the tube, how quickly does it settle?

#5 herrointment

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Posted 19 September 2012 - 06:34 PM

Check out the post by Dick Parker toward the bottom of THIS page. Tells you five things to design into/look for in a tripod.

I'm building that design right now and it looks to be a winner.

#6 SteveInNZ

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Posted 20 September 2012 - 03:24 PM

Thanks for your replies. Spreading the connection point of the legs was one of the mods on my list of things to try.

My thoughts at the moment are to use an artificial star, telescope/long lens and a DSLR. I'll take a series of images with no mirror lockup, etc and see how much the dot moves around in the image. The most portable setup with just a dot wins (that test). I thought about using a scanning laser so that the image tells me frequencies, but that is getting beyond what I'm looking for.
For the wind loading, I was going to do a longer exposure with a household oscillating fan fairly close to one end of the telescope. It won't give me numbers to three decimal places but it should provide a comparison.

Thoughts ? Critique ?

Steve.






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