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Portable Pier - AP or Parallax?

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#1 Jeff Morgan

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Posted 14 August 2009 - 07:28 AM

I have a D&G 8" refractor on order, and sooner or later I'm going to need a portable pier, 62" minimum height, 8" or 10" diameter. While the costs are fairly close, the designs are substantially different. The total weight to be supported will be 180-200 lbs. 90% of the time I will be only moving 30-40 feet from the basement storage to the yard. The rest of the time would be star party or remote observing.

So I was wondering if the CN brain trust might have some insights for me on this choice?

#2 RAKing

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Posted 14 August 2009 - 11:56 AM

I have been very happy with my A-P Portable Piers. They are solid, yet break down easily for transport. They also offer some flexibility. I can order different center tubes and struts for different scopes if necessary.

But my six inch pier sounds like a little toy compared to what you are planning. :cool:

Best of luck. It sounds like you getting one heck of a scope.

Ron

#3 D. Perry

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Posted 14 August 2009 - 01:54 PM

Sixty-two inches high?! Be careful on that ladder (during setup, that is)!

Have you looked into ATS (Advanced Telescope Systems) also? I've had one (albeit only 36" high) for the last 3 years and I've ordered another one for my new mount. They're extremely sturdy and don't require any tools for setup and breakdown.

http://www.advancedtelescope.com/

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#4 LLEEGE

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Posted 14 August 2009 - 01:58 PM

The AP portable piers are rock solid. I have an 8" that I use my 1200 on. It is a bit of a pain to set up and tear down though. So much so, I just got a Meade giant field tripod that is more convenient to use. Not sure if that will go to 62".??

#5 bluestar

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Posted 14 August 2009 - 03:18 PM

I find the turnbuckle struts on the AP mounts always getting in the way and are a PITA. I'm getting a Parallax for my AP1200...here's a pic of a past short-owned AP1200 I mated w/a Parallax I shouldn't have sold but I had too many domestic distractions so now I'm having a do-over :grin:

That said, I don't know how the Parallax would perform on uneven/softer ground, especially considering the heights for big refractors. For star parties the AP pier may be the better choice w/the bigger footprint.

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#6 bluestar

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Posted 14 August 2009 - 03:29 PM

Here's a shorter AP pier I have for comparison to the Parallax...

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#7 Jeff Morgan

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Posted 15 August 2009 - 12:50 PM

Sixty-two inches high?! Be careful on that ladder (during setup, that is)!

Have you looked into ATS (Advanced Telescope Systems) also? I've had one (albeit only 36" high) for the last 3 years and I've ordered another one for my new mount. They're extremely sturdy and don't require any tools for setup and breakdown.

http://www.advancedtelescope.com/

Regards.


The ATS is nice, but 2.5x the cost of the other options. Ouch!

I've been thinking (perhaps too much) about assembly. It's not so much that the OTA is heavy, but cumbersome and expen$ive. So I was considering a special device to do the lifting for me. Take a crank winch (like on a boat trailer) and have it welded to a fixture that has a swing arm. Attach the fixture to the pier via a quick release or strap clamp, and crank the OTA into place.

#8 gnowellsct

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Posted 15 August 2009 - 01:03 PM

You might consider the Losmandy HD Tripod with an extender. See the FHD series here:

Losmandy FHD tripods

BUT I decided against the Parallax pier design because there is not much adjustability for unevenness in the terrain. Ditto the AP. The ATS piers are half way between the extremely terrain-flexible Losmandy tripods and some of the other protable piers.

I use the ATS, however, at about 42" height, and it is nice to have a bit of usable space underneath the tripod. you don't have that in legs-on-ground designs (i.e. legs spread out full on ground).

I should mention that the ATS pier is extremely light weight for its size. People are always surprised when they ask and I let them heft it.





good luck,
Greg N

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#9 Jeff Morgan

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Posted 15 August 2009 - 01:06 PM

I find the turnbuckle struts on the AP mounts always getting in the way and are a PITA. I'm getting a Parallax for my AP1200...here's a pic of a past short-owned AP1200 I mated w/a Parallax I shouldn't have sold but I had too many domestic distractions so now I'm having a do-over :grin:

That said, I don't know how the Parallax would perform on uneven/softer ground, especially considering the heights for big refractors. For star parties the AP pier may be the better choice w/the bigger footprint.


Thanks for the post BlueStar. I was hoping someone out there had used both. I like your reasoning overall. AP doesn't publish all the stats, but it looks like the footprint is a bit bigger (the Parallax mount scribes 43", much larger than it looks). Arizona is mostly rock, dust, and uneven ground. Even areas that appear flat give me challenges with a 12" Dob.

When I look at the Parallax mount I like the "clean" design and it looks very quick to assemble. If I pour a concrete pad, it could be the winner. But I also wonder about how robust the connection point is between the pier and legs.

Losing the zenith is disappointing, but a secondary factor. I guess the next step is to get on the phone with AP and get more stats, then fire up the drafting program to see how much of the zenith is lost.

#10 bluestar

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Posted 15 August 2009 - 07:27 PM

My 8" AP pier spread is 49"
My 10" AP pier spread is 51"...pier is 2 inches wider ya know so it figures ;)
Yes, the Parallax is ideal for a concrete or hard flat surface. I have found it much easier to assemble than the AP pier; each leg connects to the pier with 2 large screws w/black handles so it's quick and no-tool...NO flexure here of any kind...and very similar to my Parsec/12. The sleek design suits my observatory where space is a premium...I can move my observing table/cart right up snug to the pier w/o turnbuckle rods sticking out and limiting maneuverability...a smaller, lower 43" footprint and tighter operating radius.

The previous owner of my first Parallax pier also had an AP1200 w/big heavy apo and he was scared of it falling over in the field so he put additional weights on top of the legs/feet...thats why he sold it...so that may answer the ? or maybe he was just paranoid due to the $$ on top :shocked:

In an ideal world, which your thread got me thinking, was to have an observatory pier (Parallax) and field pier (AP)...still less than one ATS portable pier.

I used the Losmandy G-11 tripod w/pier extension and this worked fine for my 5" long focus refractors but going 6" and up I think comes up short.

Pic'd is my previous Parallax pier w/Tec apo...and additional weight the owner used...

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#11 bluestar

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Posted 15 August 2009 - 07:28 PM

Closeup of the Parallax leg attachment...

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#12 bluestar

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Posted 15 August 2009 - 07:29 PM

The Losmandy G-11 tripod w/pier extension w/D&G 5" f/12...

Both the Losmandy HD and FHD tripods have a max height of 48"; the pier extension is listed for usage only on the HD.

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#13 bluestar

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Posted 15 August 2009 - 07:52 PM

And then there's an ultimate partial solution, the PierTech hydraulic adjustable pier...you can load the scope at a lower position and "power" it up 20" to a max of 58".

http://www.pier-tech...escope_pier.htm

#14 bluestar

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Posted 16 August 2009 - 11:08 AM

For visualization purposes, here's my Parsec/12...60" pier, 43" leg spread minus turnbuckle-system supports...sleek and solid. Similar to the Parallax product but the former is MUCH heavier...the Parsec mount w/counterweights MINUS ota is in the neighborhood of 150 lbs! And yet it was marketed as portable...owing to the quickly attached leg system.

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#15 DeanS

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Posted 16 August 2009 - 11:35 AM

I have the parallax for my AP1200, it is about 36" total height. I would not feel comfortable with a taller one, and especially with a large refractor on it.

#16 bluestar

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Posted 16 August 2009 - 12:03 PM

Thanks for that insight Dean...surely give me pause for thought...that's two users against the tall Parallax portable pier for big refractors :question:

#17 bluestar

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Posted 16 August 2009 - 05:28 PM

I hope he doesn't mind me posting this pic but here's fellow CN'er Larry T. with his 8" f/12 D&G/Parallax portable pier combo (also discussed here http://www.cloudynig...hp?item_id=1255 )

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#18 Jeff Morgan

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Posted 16 August 2009 - 07:05 PM

I never considered the Losmandy, did not realize it was rated for about twice the load I anticipate.

#19 Jeff Morgan

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Posted 16 August 2009 - 07:10 PM

I corresponded with Larry on this, he really liked the Parallax with the longer plate. And you know, every time I get a little anxious for delivery of my scope I come to CloudyNights and re-read that review!

#20 DeanS

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Posted 16 August 2009 - 07:24 PM

That is a huge 'portable' set up :) Looks stable, at least when it is balanced well.

I have the losmandy G11 tripod that I used with the Mach1, that I just sold. It was very nice. I have a 900 coming next week and plan I using it on this, along with the extension if needed when I do visual with the TOA.

#21 ltha

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Posted 18 August 2009 - 09:41 PM

Hi Everyone,

Pat mentioned you were chatting abut piers so I thought I'd add a comment or two. I very much liked the Parallax pier and felt it was fine for the 8" F/12 D&G, especially with my interest in visual observing. The height on mine was 60" which was about right but a few more inches would have helped when viewing at zenith. Of course, mounting a guide scope near the rear also puts the tube further forward in the saddle which also gives a better eyepiece position when near zenith. It seems to me that the biggest issue is the long tube and vibrations inherent in something so lengthy. The 39" saddle plate was a huge improvement and after adding it I really had no problems with performance at all. The only thing with the Parallax pier was that it was a light gauge tube. A friend who makes a lot of his own stuff said he'd have gone with a heavier gauge to add weight and stability. If the light gauge tube was less stable, I never noticed it.

I have never seen nor used the taller AP pier, but the few shorter versions sure looked like they were sturdy and high quality.

#22 bluestar

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Posted 19 August 2009 - 03:05 AM

Nearby dealer Company 7 has the rare Astro-Physics 206mm on display in their showroom, on the 10" and tallest AP pier, 1200 GTO and believe me, that mount/pier combo is rock solid and imposing. Many a time I've stood there and stared in awe at that rig, but in the cramped confines of my rolloff those darned struts are a major annoyance.

Thanks Larry...I'm sold now...Parallax for BlueStar and an AP for the road. All I need are longer turnbuckles and tube...I already have the legs.

#23 ltha

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Posted 19 August 2009 - 09:35 AM

Hi Pat,

I read back over my notes from the last few years and there was one about ordering a permanent pier from Parallax if I did a permanent installation of the D&G. Not needed as far as stability, but a cleaner installation with a smaller foot print. Plus they look so neat!

#24 bluestar

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Posted 20 August 2009 - 03:16 PM

Hi Everyone... The 39" saddle plate was a huge improvement and after adding it I really had no problems with performance at all.


Hi Larry,

Thanks for jumping in the pier discussion for these big refractors...

I'm making some templates for the local machinist to do some custom mounting plates for my mounts (he did the one for my previous pure D&G 5" f/12-DG150 mount rig [gosh that was nice visual setup])...turned out pretty good but the thickness aluminum I spec'd was a bit thin; it did ok on that mount/scope but I don't want to make THAT mistake again now w/the 8".

For a D&G/AP/Parallax combo what thickness metal (aluminum I assume) plate did you use? The biggest AP mounting plates are 24" length and 1/2 inch thickness.

#25 Jeff Morgan

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Posted 20 August 2009 - 09:47 PM

I find the turnbuckle struts on the AP mounts always getting in the way and are a PITA. I'm getting a Parallax for my AP1200...here's a pic of a past short-owned AP1200 I mated w/a Parallax I shouldn't have sold but I had too many domestic distractions so now I'm having a do-over :grin:

That said, I don't know how the Parallax would perform on uneven/softer ground, especially considering the heights for big refractors. For star parties the AP pier may be the better choice w/the bigger footprint.



I called the folks at AP today to get some dimensions on their portable pier. On the way to work I was able to do a quick and dirty drawing, and it appears there will be (ironically) a bit of a Dobson's Hole with this pier.

Here are the key known numbers:

- Pier Height: 62"
- Turnbuckle height: Top - 19"
- Turnbuckle angle: 30 degrees from vertical
- Height of EQ head (DEC and RA axis intersection): 13"
- Distance from center to saddle plate edge: 8"

There are a few unknowns:

- The precise balance point on the tube. The only equipment I intend to hang off of it will be a 8x50 finder, Telrad, Maxbright diagonal, and eyepiece. For planning purposes I used the center of a 92" tube.
- The taper profile of the tailpiece end. Where does the tube end and focuser begin? How long is the focuser body and what is its diameter?
- How much separation the Parallax rings provide from the saddle plate. This effectively moves the scope further from the pier center when pointing at zenith.

Also, my sketch does not show any focuser travel, or star diagonal. Guess I need to call Barry at D&G for a few numbers.

They had no problems with the total weight I was planning to carry (180#). As to the uneven ground, I was told the portable pier has little provision for this. The solution is the ATS pier, or to use a few wood blocks under the low leg. Plenty of wood blocks laying around the the Wile E. Coyote School of Telescope Making. :grin:

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