Rusted

I bought a brand new pair of 10x50 Zeiss Jenoptem decades ago. They were out of alignment from the very first trial at home. The shop in Bangor N.Wales was not interested. Told me I must have dropped them. I hadn't. They were treated with kid gloves but they gave me nausea. So I set them up on a fence post and adjusted the objective rings to realign the images. They have remained perfectly aligned for the ensuing three decades. I have a dozen pairs of charity shop bought binos. £5-15. Almost all of them are misaligned porro prism. They still make good finders. Bung them in a bit of PVC plumbing pipe for an inverted image.

I looked back through this thread and it seems I was still H-a Negative back in 2018. This is my home made, H-a Positive, iStar 6" f/10 H-alpha, PST mod, on my home-made GEM. All housed in my home-made, 3m, trapezoid dome on top of my 2 storey, home-made, octagonal observatory. Full aperture 160mm Baader D-ERF, PST etalon, 50mm KG3, 50mm Baader 35nM H-a, Maeir ITF, Lunt B1200 BF and ZWO ASI174 camera. My L-shaped, imaging desk is isolated from, but wrapped around the 14' high, pyramidal, timber/ply pier. The 27" monitor is hung from the pier on a fully articulated, universal bracket and shows a typical view as I process a nice prom in AS!3. It is difficult to be far enough away to get it all in within the confines of a 3m 10' dome. Being retired, I practically live in my observatory whenever the sun is shining. Sometimes before 8am to after 7pm on the sun alone. Longer still, if I image the Moon. So the cost per hour, is dropping like a stone. The telescope is superb in white light and on the moon too, without removing the pre-etalon filters. I just fit a different rear end. You can blame all this on Sir Peter. He turned me to the Light Side so perhaps we ought to call him "St. Peter."

It's good to eliminate alternatives rationally. How brief are novas and supernovas?

It's odd that none of these 'townies' has noticed that most cars are fitted with headlamps.

Blue? Probably a copper coated neutrino.

A few more paving slabs to make more room? I'll see your 16 spots and raise you "Close Encounters Landing Strip." The young are terrified of the dark!

If you enter your time and coordinates into a planetarium software you can check for objects at that location.

Too much cloud and too large an area to capture it all in one 800x600 frame. 1500mm x 2.6 GPC. Pushed these much harder than usual with a double dollop of sharpening in PhotoFiltre7.

Still mulling over how to progress. My painted plywood dome is still leaking and getting worse. The paint is peeling badly now and the [very] expensive marine sealant is cracking all over the seams. The European Pulsar importer wants €1500 for delivery via a haulage contractor. With an extra €200 for Pulsar's sage green, the cost of the 2.7m has risen 50% to €6000 delivered! [£5,500.] I feel as if I am being put on the rack because they have the monopoly on supply. Two months waiting time too for green! Deep into autumn over here and a lot of rain can fall in two months! An older 2.7m GRP dome is up for sale only 30 miles away for £700 equivalent. Only a trailer collection away during a pandemic with only me at the drop off point to unload it. Similar up-and-over shutter to a Pulsar but it uses rolled steel rails for the shutter and dome rotation. One piece construction means a single, heavy lift. Rather than my dragging individual Pulsar segments bodily up a ladder. This older dome needs some "tarting up" and painting sage green from filthy white. Which can easily be done on stands while safely down on the ground. Hired telescopic loader/lifter or bribing a local farmer to lift it up onto the second floor during baling? The option still exists to cover the existing dome in GRP. Or self-welded, heavy duty, PVC tarpaulin. I favour the latter but my wife thinks it will be loose and ugly. I'd try very hard to be sure it wasn't. Though you can't easily remove the creases from the tarpaulin from being folded for storage and delivery. Perhaps the creases would respond to some gentle heat while under tension? I have repeatedly measured my existing dome and placed straight edges across the base ring, etc. A 2.7m hemisphere is only 1.35m high from the base ring. My existing dome is 2m high to the bottom of the zenith board! With my 6 & 7" refractors in there, on my huge GEM, I am still in serious doubt about a 2.7m's usefulness. My 10" f/8 Newt would never fit if the sun really does go into hibernation and I need a new hobby on the dark side! My present dome is perfect, in size, colour and form except for the leaks. So, I'm still thinking [and talking] aloud and making zero progress as we suffer a rather poor summer. Warmth is highly desirable for GRP [yuk!] Which I'd still much rather avoid! Or, heavy PVC manipulation and welding of shaped gores on top of a 20' [cantilevered] ladder. I can staple each gore in place and then cover the staples with the next overlapping gore. It is all straight lines. I could do the PVC cover to provide a few years of waterproofing for only about £200 equivalent. Welding the PVC with a heat gun really doesn't look that difficult for someone, like me, with decades of DIY experience.

I don't get why you don't remain both mobile and fixed simultaneously. With our 20' hedges and 60' trees I was pushing massive steel piers on wheels around the garden. Still not remotely as efficient as a permanent pier set-up which is always aligned. For the 10" you can easily rig a trolley to drag it around effortlessly. Just choose your wheels/tires to match the terrain. Solid tires with flat treads on lawns. Not pneumatic. Which rock far too easily on the air cushion. Or have you already sold the 10"? Did I miss that?

Thanks for the excellent review. I wouldn't swap ether of my 2" ClickLock fittings for anything with thumbscrews. Though I do have to regularly re-tighten all the tiny, hex-socket, grub screws around the perimeters. Probably something to do with the massively cantilevered H-alpha etalon/filter/focuser on the 6". Or the hefty 2" Lacerta Herschel prism set-up on the 7". Still far more secure than three large thumbscrews and a compression band fitting.

Hi, Weather, cloud, poor seeing and drive problems have hindered recent output. Today's southerly disturbance images are just to prove the sun isn't quite blank. Seeing awful today, too, but at least I can play again.

If you want to impress with outreach then use a larger computer monitor but make sure it is well shielded from the sun. I routinely see sharp H-a images with the [partial] solar disk up to a meter in diameter on my 27" monitor. The same goes for the moon. Viewing with an eyepiece requires lots of practice to see much at all. I can prove this simply by using my left eye after decades of only using my right eye at the telescope. My left eye is not "educated" to see anything much at the eyepiece.

What's this nonsense about Solar imaging? Can a dewshield double as a rain hat? Thought not. BTW: Nice images!

What an amazing job you've done! Love the brass details you've added! Very much in keeping with the classical look. Congratulations!

I kept looking for Neowise but there wasn't a sign. To which my wife responded: "It's behind you!" She was right! As usual.

Just put them on upside down.

I like the red handles! Fewer "senior moments" forgetting to lock everything down on leaving.

Hmm.. 🤔 I'm definitely looking forwards to the Mk17G[3]a 😎

What about a large dog using the obsy as a kennel? 😱 For combatting wind lift it would be very simple to saw or file a narrow slot in the wall flanges just below the bulging wall rim. Just cut enough away for hold-down hooks, attached to the lower edge of the inside of the dome, to pass safely through. I doubt the strength would be much reduced. The flanges are merely location devices for easy and accurate dome wall assembly.

You could arrange ramps to lift the security hooks clear at the flanges. Though you'd probably have to replace the hooks with disks for smooth operation. Bent strip metal would do for the ramps. No need for them to be solid. Though you'd still need to ensure the disks weren't left lifted clear when leaving the obs. The disk support arm would need to be sprung outwards. What's causing this strike through text?

Is there no way to have permanent hold-downs independent of dome rotation? Here is my solution to the problem: The hefty disks prevent lifting at all eight, support and steering wheel locations: The stainless steel, shelf brackets are incredibly strong and stiff. Having permanent dome retention at all orientations ensures security against lifting. Unfortunately I am not yet familiar with Pulsar's exact moulding details. So cannot confirm whether there is a continuous base ring or horizontal rim to use for dome retention. I never liked the idea of having to manually set security latches on leaving the dome. Far too risky for it to be easily forgotten! EDIT: Just checked Pulsar offer permanent security hooks so the domes do have a lip, ring or rim for retention. I had to paint in the top edge of the hook to make it visible. 2nd EDIT: Duplicating the Pulsar HD brackets with metalwork from any DIY store would be very simple. Bolt an angle piece to the flange below. Then bolt a straight strip with a built in hook for the upright piece. Preferably in stainless steel. Stiff and non-rusting. Say a fiver each per hook if you have the bolts handy?

A little research shows that condensation in observatories is commonplace. Almost regardless of how well they are sealed. I left the floor wide open between the joists on my second story dome. Spaced the larch floorboards apart to let the floor breathe. There is ventilation all around the base ring and on either side of the bi-parting shutters. A ventilation slot is above the double doors out to the veranda. The ply clad, 14' high, pyramidal pier is wide open on the western side. Still the plywood dome and walls would get damp inside with condensation in winter. I lined the dome with black agricultural fleece spaced off the ply cladding. It is probably black [or white] with mould out of sight. Perhaps the real answer is closed cell insulation on the inside of the dome? Black, closed cell, camping mattresses are available in about 10mm thickness. Shopping about would make the purchase of enough material almost trivial. Putting a dehumidifier in my dome would be like trying to dry the entire Earth's atmosphere!

Granulation is aperture, seeing and magnification dependent. I like my SC simply for reducing the glare in visual white light. I don't do WL [nor visual] often enough to be able to confirm increased clarity of granulation. Particularly by comparison with and without the filter. It sounds like the sort of project to be practised [diligently] when the sun is featureless. Or, when the sun is actually visible for more than fleeting moments in this overcast!

8x42s are so light you may soon take them everywhere with you. A revelation after heavy 10x50 Porros! I take my 8x42s on my morning walks and never notice the weight. 8x42s are bright, compact, sharp and easy to handle when spotting birds or wild animals. Use a short, wide strap to keep them high on your chest and not swinging around as you walk. 8x is like having image stabilization compared to 10x. In my own experience. The car roof and [damp] elbows provide all the IS I need when looking upwards through binos.