Where would you put a Pier?

[Andy01]

Hi everyone,

Wifey has agreed for me install a pier in the backyard :)

So do I put it in the grassed area or on drill into the pavers surrounding the pool?

There is significant LP from the spherical security light in the retirement village next door (arrowed), but this is somewhat lessened when I set up on the tiled area. It does however produce noticeable gradients in my AP when shooting west.

I'll mostly be doing narrowband from home, and LRGB from country dark skies.

These photos are looking due North, from Melbourne. I have a brilliant view East, all the way to the horizon (I'm on top of a hill) and pretty good views South. West is compromised by the LP and a large new 2 story house next door.

Has anyone any experience with drilling a Pier into tiles? Will that work?

Cheers

Andy

[MrB]

Joy!! :D
I would go for the grassed area with a good concrete footing. The paved area may be appealing now for its apparent simplicity, but I think you will soon find the pier will be in the way down there. Your pavers, though large, won't have suitable footprint or mass for bolting to directly.
My own pier (http://www.iceinspace.com.au/forum/showthread.php?t=118162) is on a ~360kg block of concrete which is probably considered on the small side, but is adequate for the small scopes and short focal lengths I work with.

[sharpiel]

Can you attach a screen to your fence to block that light? Might extend your pier options...

[leon]

As mentioned by Simon, definitely into the ground, there is no stability on tiles/paver's.
a decent concrete footing of at least 600mm cubed, or more would do the trick.

Leon

[Andy01]

Lol :) I attached a couple of tarps on stakes to the top corner of the fence to block out that light, but on the first windy day they were like topsails on a clipper ship! The fence was bowing & moving like a trampoline so I had to take them down when the fence base cracked!

[lazjen]

You might be better off with something you can raise/lower (like a sail! :) ) - since you're probably only going to need it up when there's little wind anyway.

[g__day]

I would do the grassy end near the offending light - and at the least put up a screen to block the offending light - and/or ask the owners of the offending light to instal one with a shade so it only directs light downwards (maybe offer to pay).

If you wish to put a pier on pavers - do what I did; lift a lot of them, dig a big hole and fill it with cement and as it dries but 18 inch long 1/2 inch wide galvanised bolts into it so they just protrude above the level of the pavers. Then you drill holes thru the four pavers above the bolts and relay all the pavers on the drying cement. This structure should certainly be secure and stable! If you ever want to take your peir and leave the backyard untouched - just lift the four pavers, grind off the bolts and re galvanise their ends with Gal paint - then lay four new (or aged) pavers over them; no one would ever know you had a pier there.

[Andy01]

I work with a 660 mm refractor, might be a good idea reproduce your footing :thumbsup:





That's a clever idea, hmmm ;)



That's very clever, you guys are amazing! :thumbsup:

[PeterEde]

Where is the sky most visible? I'd put it on the grass and maybe put up a section of shade cloth to minimise the LP.

[Andy01]

Hi Peter, there are unobstructed views from ENE all the way through to SW, but from SE to SW it's only from above 30 degrees to clear my house!
Ok-ish views W to NW but that's where the LP is most noticeable with my OSC camera.

A shadecloth would be great, Lazjen's idea of a raisable one is clever too :thumbsup:

I have a new QSi WSG8 camera on order, with a full set of Astrodon LRGB & Ha, O2 & N3 5nm filters.
Is narrowband imaging badly affected by LP? Do you think the security light will still be problem with the new camera?
Cheers

Andy

[The_bluester]

I was going to suggest on the grass if there is a sufficient area of sky visible. You know that you have a helper with shovels to dig a hole in trade for beer and BBQ!

Now we just have to finalise a location for piers then shed at my place. I am angling toward my first idea again. Just have to get approval to carve out a bit of the paddock for it.