socially acceptable astroshed

[Horwig]

Thought I'd share these.

Built last summer, the pier is a 6 inch sq section steel tube running inside an 8 inch tube, the 6 runners are for pop up tv cabinets: (popuptvs.net)

The linear actuator comes from IDGB : (actuators-electric.co.uk ) and is a 60 cm lift 24v device.

The pier sections can be locked by M12 bolts between sections, but to be honest, most night I don't bother. Scopes are an LX200 10" and a Borg 100ED, images are with a Canon 450d.

Some would say that the pier is far from sturdy enough for imaging, but I think the M42 narrow angle image is fairly sharp, (though not processed to my satisfaction!)

It's built on the base of what used to be a brick **it house, which is mighty strong enough...

Huw

[Gina]

What beautiful images!

[Horwig]

Thanks Gina, I'm proud of the widefield mosaic, but the narrow angle was the final image from my 450d, (hence the disclaimer to its quality), I bumped into it in the dark and broke the usb socket off the board amongst other damage. That was the end of that camera...

[JKB]

Love it, great idea! Pictures are fab too. Now all I need to do is convince my wife

Cheers

[RobH]

Excellent

A telescopic pier that holds polar alignment is the holy grail, and I'd love one (actually, two :-)).

Obviously, from your fine results, it's good for widefield work, but what's the consistency of polar alignment? Do you have to change guiding parameters or can you leave them the same over several nights with the same system?

Have you tested it at a long FL?

Cheers

Rob

[Horwig]

Hi Rob, yes polar alignment consistency was a big worry, hence the locking screws that fit into dimples in the inner tube, but the truth is that the runners are so tight that it seems to hold alignment well. I've tried putting my qhy5 guide camera on the lx200, centering the target on a star with the pier extended, then dropping and re elevating the rig, and the star is still relatively close to the center, yes, if I'm honest there is small field rotation in the uncropped M42 image as can be seen, but I think I'll live with it. The image is a single 5minute sub at f6.3 (1575mm focal length?)

Huw

[RobH]

Thanks Horwig, and great job.

Cheers

Rob

[Pete Presland]

some very socially acceptable images as well,very nice obsy and lovely images.thats a very interesting pier

[Ransu]

The pier is great and wide orion image is beautiful. Thanks for posting!

[Earl]

Nice idea and the results speak for themselves !

[Horwig]

Thanks everybody for your kind words.

I was very worried when I designed it that the pier would never be rigid enough for imaging, having seen other designs. The concrete base of the old toilet was solid, but not that thick. so it was a risk to bolt the pier to it. The pier is 1/4 inch box section steel on a 1/2 inch steel base , so is massively heavy. The secret weapon is that I didn't demolish the bottom 12 inch of the **ithouse wall, which is 4 inch deep dense concrete block. The pier is bolted through this with 1/2 inch bolts, and I reckon that this is what gives it it's rigidity.

Also, the slides between sections are very stiff, indeed, without the telescope and mount, the top half of the pier didn't even drop under its own (not inconsiderable) weight. so sideways wobble is not a problem.

At this time of year night hardly falls, so here's to darker Autumn nights!

Huw

[nightvision]

Very impressive use of technology and mechanics to reduce the obs build, got me re-thinking my design.

[Horwig]

I'm adding some more construction details in answer to a pm from Rols asking for construction details and what if anything I would change. I'm answering here in case they are of interest to others.

There never were any plans, it was very much a case of make it up as I went along.

The floor is 4x3 timbers, with a covering of 18mm ply. Matting is industrial rubber matting - soft enough for stuff to bounce off, and hardy enough to survive damp and wet feet. The frames for the wall are 4x2 timbers, clad in 4mm ply and then clad in shiplap t&g boards nailed and glued to the frame and ply. Internal dimentions are 1.75 meters sq. The lift off roof panel is made out of 2x1 inch ali box section, pop riveted together. The hinged panel is 3x1 timber frame covered in 4mm ply. Both panels are covered with lightweight plastic sheet:(PVC Plastic Box Profile Corrugated Roof Sheets)

The top panel is insulated with 1inch polystyrene board, both roof panels are held together with the arrangement shown in the photo, the rear of the roof slides under the shed weather board.

If I were to start again I would make it slightly larger, being clumsy and working in the dark don't go together, and I have a dead canon 450d to prove it!!! Also headroom above the scopes is very limited, it was fine with just the 10" Lx200, but I now have a 100mm refractor, and a filter wheel and camera to accomodate. So if in doubt, go larger.

Hope this and the pics help.

Huw

[laser_jock99]

Looks like an interesting solution.

[Freff]

Very innovative.

[Rols]

Thanks Huw, it leaves me with a lot to think over, i now have the 12" sitting around and a decision has to be made.