In Search of Dark Skies - My Search Is Over - GifNet.US Observatory

[SkyHiker]

Good thread Chris!

Thank you. Once the design is finished, I am going to try and write something up to the effect of, "How to design your own Observatory for Dummies" only using two special triangles.

Did you check Graeme's link? He first built the pier, then put a long stick on it and slewed the mount around to determine the wall height. Easy peasy.

If money is an issue, I would prioritize the piers over the warm room and the outside pad section, get a COTS metal shed that you modify for roll off, and make the pad as small as possible.

I think you can cut back on the size of the pad by putting the observatory at 45 degrees with th N/S line because the saddle is the lowest at 90 degrees in RA, which makes 0.5' difference in height. The corners are distinctly lower in the FOV than the walls at the closest point.

I will test my simulator with my own obsy and mount then run it again for a 45 degree position to see how much smaller it can be made.

[chris_g]

Good thread Chris!

Thank you. Once the design is finished, I am going to try and write something up to the effect of, "How to design your own Observatory for Dummies" only using two special triangles.

Did you check Graeme's link? He first built the pier, then put a long stick on it and slewed the mount around to determine the wall height. Easy peasy.

If money is an issue, I would prioritize the piers over the warm room and the outside pad section, get a COTS metal shed that you modify for roll off, and make the pad as small as possible.

I think you can cut back on the size of the pad by putting the observatory at 45 degrees with th N/S line because the saddle is the lowest at 90 degrees in RA, which makes 0.5' difference in height. The corners are distinctly lower in the FOV than the walls at the closest point.

I will test my simulator with my own obsy and mount then run it again for a 45 degree position to see how much smaller it can be made.

Money is starting to become an issue. So instead of a warm room, I can bury an ethernet cable from the office in the house to the observatory, something I weas planning on doing anyway. I would also have to add USB over Ethernet to the design. Piers instead of tripods would also let me set up a small desk in the obsy room. Two pedestals would most likely cost less than the warm room. I'll cut the outdoor pad if I need to cut costs and add it later. I can always set up on the ground like I do now.

I just scrolled through the thread and am not seeing a post from Graeme on a pier. How deep and wide should the hole be made to properly support a pier if I bolt one down to the pad itself instead of burying a pedestal? Figure the pier would have to support up to 100 pounds. Bolting to the pad seems to be easier in my mind instead of burring a pedestal and going through the machinations of lining it up, I could also unbolt the pedestals later on if the need ever arose to decommission the Obsy.

Interesting idea about a corner pointing north instead of the wall. Looking forward to seeing the simulator results...

Ok, no warm room at this point in time, but the design must support the addition later.

[Gordon]

Of course if you are using a contractor, would it not be more efficient to have them pour 2 pier bases with rebar sticking up while they're at it, so you can pour concrete piers on them? In that case don't forget to put tubes for power and communication lines on before they pour the pad, that's something you can't do after the fact.

Conduit for power and comms will be buried prior to pouring the pad, pier or no pier.

I'm looking at the pics @Gordon posted in Rimrock, https://theskysearchers.com/viewtopic.p ... 82#p203282.

A pier base, a 3x3 concrete pad with a hole in the middle of it for a pedestal. It looks simple enough. How deep does the hole go? I remember reading threads about perma frost, water tables and such. Using a pier though loses the flexibility of a variable height tripod. I did measure from the base of the EQ6's tripod at full height, 58"x58', 36"x36" at its lowest. The AZ-EQ5 is also 36" at its lowest. Don't know what its widest is though.

In keeping things simple and initial construction costs down, could I not bolt a pier to the pad at a later date? https://optcorp.com/collections/telesco ... crete-base or https://optcorp.com/collections/telesco ... er-42-inch. This one has that magic number of 42" height.

This was built in southern California so no problem with a 'frost line'. Also the ground stays pretty dry so no water table to worry about.
I dug a hole with a post hole digger about 3 feet down. Then placed a metal fence post in the middle (you can see the middle hole here https://theskysearchers.com/download/fi ... =29678&t=1.

If you wanted to place a premade pier on top instead of the concrete pier that would probably work fine. Just make sure to use the best concrete anchor bolts you can find.

[chris_g]

Also the ground stays pretty dry so no water table to worry about.

That's my concern water table is high here. Where I'm at there is a bayou (I think y'all call them byways ) that also has the potential to flood part the property.

So, I'm thinking a 1'x1'x1' hole at center point of each 3'x3' pier station, then pour the pad. Maybe deeper if the ground supports it. Best quality concrete anchor bolts money can buy!

[SkyHiker]

For an 8x13x5.5' observatory at latitude 30 degrees, mount placed at (9,4)' at 45 degrees with the N/S line with a 6" Mak-Newt on it, I get 30 degrees clearance everywhere, on the South side 20 degrees if you keep the OTA on the East side. I assumed the same mount dimensions as my G11, as the saddle height is about the same.

Observatory view, alt clearance and RA/DEC clearance maps below. So, there is a size advantage to placing the mount (North leg aligned with the N/S line) at 45 degrees relative to the building.

Here's a $700 8x12 shed with the gable base at 5.5'. If you can reduce the space between the mounts to 4' this could work fine. It depends on what size OTA you put on them and where they are pointing at. I suspect that could be made to work. From the picture you can tell that is should not be too hard to separate the roof at 5.5' (it looks like the gable is a separate panel) if you add wood framing on the inside and add rails. Let's take the final calculations offline to make sure the dimensions are correct.

[Graeme1858]

I can bury an ethernet cable from the office in the house to the observatory, something I was planning on doing anyway.

I ran an ethernet cable to a PC in the observatory. I set up the telescope then move indoors to sit in the warm on another pc using Teamviewer to control the observatory PC.

My link is in my signature.

Graeme

[chris_g]

My link is in my signature.

I am in the process of redesign of my web site. It's all slow work. https://www.gifnet.us and https://observatory.gifnet.us I like your layout.

Now, looking at how you dug and poured the pier, I am thinking I thought the same thing. The depth appears to be six inches based on your bricks, standard size 2".

So, two 1.5 x1.5x1' holes dug for pier pedestals then standard pad poured on top of that. Pier pedestals are under the pad instead of on top. Supports the standard use of the building if it were ever decommissioned.

Thank you.

Clear Skies,
Chris

[Graeme1858]

I am in the process of redesign of my web site. It's all slow work. https://www.gifnet.us and https://observatory.gifnet.us I like your layout.

Now, looking at how you dug and poured the pier, I am thinking I thought the same thing. The depth appears to be six inches based on your bricks, standard size 2".

Cheers. It's just a Google Sites template.

The concrete under the pier is a 2ft cube.

Graeme

[chris_g]

The concrete under the pier is a 2ft cube.

2 cubic feet under the pier, would that measure include your pad and what you pored or a two cubic foot hole, oh my aching back! Two of them!

[SkyHiker]

The concrete under the pier is a 2ft cube.

2 cubic feet under the pier, would that measure include your pad and what you pored or a two cubic foot hole, oh my aching back! Two of them!

2ft cube = 8 cubic feet, ache some more!

[JayTee]

My pier started as one cubic yard (9 cubic feet) 40" down. As it turned out, I didn't have the gumption to do that much work. So I went with 8 (2'x2'x2') cubic feet 30 ish inches down. As it turned out, this was more than enough of an anchor for the pedestal.

[Graeme1858]

2 cubic feet under the pier, would that measure include your pad and what you pored or a two cubic foot hole, oh my aching back! Two of them!

The top of the 2ft pier block is 1ft down below the timber finish floor level.

Graeme

[chris_g]

In preparation for the move, I decommissioned the backyard observatory and packed it all up. When I think just how much is sitting in such a small space, I almost choke!

The EQ6-R and its tripod are the only pieces that don't have custom storage yet. But I have the original boxes! Over the last couple of years, not a lot of excess equipment that doesn't get used. Only two pieces, the 7 position 2" filter wheel, however it will end up being used eventually, and the NexYZ phone adapter. I tried the adapter in the beginning, but it wouldn't hold the weight of my Note 20 Ultra. My S22 is just as heavy. The Z axis, at least in my mind, is a gimmick and that is where the issue is. Total, 7 OTAs, two mounts and respective tripods, 7 cameras, a Hyperion set of EP and ancillary equipment.

Looking at it, it does confirm that my G.A.S. (Gear Aquisition Syndrome) has almost run its course. Only one more OTA, mount and camera to add! But won't that always be the case, just one more telescope, please!

[chris_g]

A quick update, I have a tentative close date of the 18th of August. I've fleshed out the rough cost for everything and it all fits within the budget, however, it's tight, so squeezing things will be necessary.

Building size is 11.5 by 15.5, third mount will be the Pegasus Astro NYX-101, with optional half pier and carbon fiber tripod (may go with a heavier payload mount if I can squeeze the budget.) Two very capable light weight mounts, one with a payload up to 60 pounds, the other 15. The EQ6-R will be "permanently" in place, it's getting too heavy for me to regularly setup and break down.

Clear Skies,
Chris

[chris_g]

The date is no longer tentative but it has moved to the 17th, amazing, the New Moon. Work has graciously granted my PTO request for the18th as well. Now, I can only hope for clear skies...

[chris_g]

Hello all,

Time to wrap this thread up.

I closed last Thursday and finally was able to set up a scope last night to take a test shot with the AZ-EQ5 and the 6D, no filters. The number of stars showing up in the parked position was phenomenal, I wasn't sure if I was looking at the same sky! I am able to make out the Milky Way! I have one streetlight, neighbor security, to contend with to the west, mostly mitigated by trees. The contrast was like, WOW! After getting PA and guiding dialed in, I got one 180 second sub only find out that my working distance was slightly off; since it was a work night, I shut everything down. Now, I have no excuses for poopy data. Once I actually start construction on the observatory, I'll start a new thread to track its progress.

Thanks to all who contributed to this, @SkyHiker, @KathyNS, @JayTee, and @Graeme1858

Clear Skies,
Chris

[JayTee]

Now, I have no excuses for poopy data.

Hi Chris,

No one likes "poopy" data!