Choosing a Surveyor's Tripod...
#1
Posted 16 December 2012 - 11:00 AM
Also, does anyone have any faves on the surveyor's tripod front? The surveyor's tripods relabeled by the mount makers are ridiculously overpriced. You can generally find the same, low end surveyor's tripods on engineering supply sites for less than half what the mount head makers are asking for them, and as I said, they look to be low end tripods.
Any preference for wood or fiberglass over aluminum for such a mount? Any other features to look for or avoid?
Thanks!
- Jim
#2
Posted 16 December 2012 - 11:30 AM
There were some unexpected problems.
1) No crossbars between legs and they are free to move all the way past vertical. I put mine on a hardwood floor and the little pointy things on each leg slipped and it went kersplat on the floor.
2) The aluminium hinge area is pretty weak and 2 of them broke with my first tripod when this happened.
3) The top face of this one is curved, apparently so surveyors can fine tune the tilt. You can see the curve better in this photo link. This might be a problem.
4) Do you really want the little pointy things on the bottoms of the legs? They're great in some situations, not so good with others.
I've given up and will try to fit a Meade standard tripod to the LT6 as better surveyor's tripods will still have the same issues and the LT/LS tripod by itself seems impossible to find.
#3
Posted 16 December 2012 - 11:42 AM
Agree, in regards to the pointy leg tips and lack of a tripod spreader, but both can be remedied.
My preference would be a all wood surveyors tripod with double leg locks. I think Manfrotto sells a spreader that can be affixed to the legs and furniture leg pads or rubber tips can make the tripod floor friendly.
Universal Astronomics sells 5/8" adapters for his mounts to work with surveyor tripods and his heavy duty surveyor tripods are not a that expensive compared to a Berlebach.
http://www.universal...yorTripods.html
#4
Posted 16 December 2012 - 11:46 AM
As a general rule, wood legs will dampen out vibrations much faster than aluminum. The trade off, of course is that wood weighs more and usually costs more.
If you're looking at the surveyors tripods on the Desert Sky site, one reason they're more expensive is that they've added their own custom spreader to reduce vibrations. The question is, how much do those really help. There are lots of places you can get an inexpensive CS/Bergen tripod for about $60-70 that seems pretty solid on it's own. I've seen them online and at my local Home Depot. Not sure how much better the 2x-priced Desert Sky tripod will perform with the spreader. People who have used the Desert Sky tripod seem to report that they are very solid.
-Dan
#5
Posted 16 December 2012 - 11:53 AM
http://www.cloudynig...wflat.php/Cat/1,2,3,4,5,8/Number/3432349/Main/3421250
A quote from it: "I originally bought a tripod without the bars because it was cheaper ... big mistake. If I could do it over today I'd defiantly spend the extra money."
-Dan
#6
Posted 16 December 2012 - 12:30 PM
The most confusing part for me has been the attachment at the top. I've been also on Universal Astronomics site many times doing some "window shopping." For some reason, I keep coming back to the Sokkia tripod. You know, the beautiful green one. I'll be watching this thread with interest.
Thanks for bringing this up Jim.
Best, Linda B.
#7
Posted 16 December 2012 - 12:52 PM
http://bigbinoculars.com/obwtri.htm
or
http://bigbinoculars.com/tradeins.htm
#8
Posted 16 December 2012 - 01:29 PM
Great tip.
It looks like the short version did not sell for binoculars. For an alt-az head, though, and a telescope, the standard and tall versions are too tall, and the shorty looks to be perfect. Figure the unextended height is 32" plus 10" to 14" for an alt-az head, and that should be about perfect of an SCT or apochromat.
Regards,
Jim
#9
Posted 16 December 2012 - 11:12 PM
#10
Posted 17 December 2012 - 04:32 AM
http://i253.photobuc...G_3797_zps0c...
Since I have that 3-1/2x8 connection I have to do a little more to get mine to work. Maybe even buy that adapter to convert it to a 5/8x11 before I try anything, but I'll figure it out. I do not think it will be to much of a problem for me though as I made a thread the other day asking for suggestions so I could figure something out, and thankfully I got some replies with good suggestions. The people here have been great and very helpful.
I just now need to wait for my new scope to get here so I can see what I am working with before I move forward on the suggestions I got.
I will say that I did think about some bracing bars and a trey to go under it. Like sort of mentioned here the regular Surveying Tripods do not carry that. Which is mainly do to the fact that it would get in the way as they use a plumbob to center the tripods over the spots they are doing the measures from, and that it is just harder to get a fixed tripod to work on the many different surface contours out in the field. So I was planning on making my own. What ever I make, it has to be easily removable as I use my Surveying Tools. It is going to be easy to make. I already have some ideas and even thought of adding a cup holder.
#11
Posted 17 December 2012 - 08:31 AM
Wood tripods are renown for damping vibration, but are considerably heavier than the alloy models.
#12
Posted 17 December 2012 - 08:53 AM
I have an old military wood one that I got for free that was OD green, that I stripped and re-varnished, that is a rugged tripod. That's another place to look around - at military surplus places.....
Russ
#13
Posted 17 December 2012 - 09:02 AM
Thanks.
Great tip.
It looks like the short version did not sell for binoculars. For an alt-az head, though, and a telescope, the standard and tall versions are too tall, and the shorty looks to be perfect. Figure the unextended height is 32" plus 10" to 14" for an alt-az head, and that should be about perfect of an SCT or apochromat.
Regards,
Jim
Jim
The short version collapsed height is still 38", but extends 6" less than the standard is what I'm reading.
http://www.bigbinocu...om/tradeins.htm
I like the Oberwerk wooden tripods (own two), but think they are medium duty and may not be robust enough, as far as dampening, to handle a TEC-140.(If that's you intention.) The fixed spread is also a little narrow, imo, when handling top heavy loads.
#14
Posted 17 December 2012 - 09:33 AM
#15
Posted 17 December 2012 - 10:26 AM
#16
Posted 17 December 2012 - 11:36 AM
Those test results are no longer on the web as far as I can find. I found the URL but it's no longer available.
Leica now has made test results available showing that their tripods exceed the ISO standard performance of the Tri-Max. Many aspects of the ISO specs don't necessarily apply to telescope use but certainly the tripod's ability to maintain a stable orientation over time and withstand torque loads would be appropriate. Heavy tripods were tested with a 30kg load and light tripods with a 10kg load; twice the rated load.
Leica's results are available here; take the results as you may...
Surveyor tripod white paper
Rich
#17
Posted 17 December 2012 - 12:17 PM
#18
Posted 17 December 2012 - 02:12 PM
Tons of tripod feet here:
http://www.bhphotovi...30/N/4289955530
Tons of spreaders:
http://www.bhphotovi...29/N/4200777867
#19
Posted 17 December 2012 - 02:34 PM
#20
Posted 18 December 2012 - 02:27 AM
One thing that I think you need to keep in mind is the load that surveyor's tripods are designed to take. Having used them for their intended purpose, they are generally not used with equipment that is anywhere near as heavy as most astronomy equipment, much less a longer, heavier OTA. For truly light weight use they may be fine, but I would not risk anything heavy on one. The Oberwerk tripods are rated at 35 pounds and I would say that is the max for sure. There is a reason why heavy wood astronomy tripods are as expensive as they are.
I recently purchased a StellarVue MG-2, it's a dual sided alz-az mount with geared slow motion controls rated for 20-25lbs. It came with aluminum surveyors tripod with a custom spreader assembly. I primarly use it with my NP-101 which fully out fitted with a heavy eyepiece weighs about 13 lbs. I was very skeptical that it would be stable but it is rock solid with the NP-101, I can focus and track up to the limit of the scope (~300x) without any vibration. It is definitely sufficient for a scope this size.
I have used it with my 8 inch F/5 Newtonian, it goes about 20lbs with a lot of bulk. I handled it reasonably well.. there was some vibration when tracking or focusing but it was acceptable.
I am not sure what Jim is planning to use a surveyors tripod for but I will say I was impressed with the StellarVue. Currently it sells for $250 with the custom spreader. That's a fair amount of money, I am sure there are better values out there.
Jon
#21
Posted 18 December 2012 - 08:21 PM
Since I am looking for a GEM too for a 5.5" refractor, I might get the AZ EQ-6 and call it a day?!
#22
Posted 19 December 2012 - 12:26 AM
Regards,
Jim
#23
Posted 19 December 2012 - 02:06 AM