Rusted

Congratulations! An excellent, negative and coloured image with lots of fine detail.
You captured a lot of flaring and well contrasted filaments. All nicely balanced.
A negative image can seem more detailed and dramatic than a positive.
However your image stood up remarkably well to my crude conversion to B&W.
Then conversion to negative and finally resized down to only 600 pixels.
I hope you will forgive my meddling with your artistry.

Thanks. That makes good sense.

Wonderful detail at a remarkable image scale! 

It was just like being there. ☺️

Nice images.

It looks as if something serious is emerging around the limb.

Or is that the exit?

Good grief! 😱 Let's be careful out there! 😨

Donations to gravity are considered a serious fail/fall.

That aside: You obviously felt the need for considerably more leverage.

How does the tuning feel with just the bare coaster attached? Still too hard to turn?

NASA has clearly been overdoing the sharpening in ImPPG! Tut-tut! 🙄

Thanks. There is an Amazon branch in Germany.

No Breakaway coasters.

Thank you both.

I'll keep searching for a local source. It seems very unlikely that they aren't available locally.
They may have a particular name [in Danish] which triggers sales websites.
Fortunately they are very light. So postage shouldn't be a problem.
€21.60 for two bags of two units from Ireland.

On 16/05/2024 at 09:03, Steve Ward said:

That's a pain.

I'd be more than happy to get some off e-bay and post them to you.

Please don't. The Danish post office will want £20 equivalent standard charge for clearing customs.

Plus 25% VAT on the stated value of the goods. Brexit? Brokesit!  🙄

That's a bit posh! Royal purple!

You'd need a decent sized trailer for the panels.
Does your car have a tow hook?
If so, you might be able to hire a suitable trailer.
Car transporter?
If not, then hire a suitable van.
A minimum two person lift.
Working alone could cause serious cosmetic damage or personal injury.
Wind is your enemy.
Then your new neighbors are your new enemies.
Some people will tolerate a giant white caravan.
But have a fit over quite a modest dome.
The estate agent, who valued my hovel, hated the idea.
Told me to get rid of the obs if I wanted to sell!

These clamps aren't readily available over here. Certainly not by the 'Breakaway' name.
One shooting shop has given them a special name and are selling them at £12 equivalent each.
I wonder if a tropical hardwood, presentation box, with plush lining, is part of the deal. 😏

Genius!

Reducing the pressure adjustment problem down to the absolute simplest level:

A friction cap with a large [say] 4"/10cm? wheel/disk attached. To increase the torque available might be the very simplest option.
The Lunt drum is about 55mm in diameter. So 55/100 = a reduction of only about half the effort required. Worth trying? I am really not sure.

Simply reducing the considerable physical effort required might actually minimize the image wobbles.
Only hands-on testing would confirm this.

A friction cap for the Lunt drum adjuster with [say] pencil sized levers [capstan style] to apply the effort manually.
This would reduce the physical effort required but might not alter the risk of image wobbles.

I rushed off to find my unused 60MT and quickly discovered the severe strain on my own strong, but aging, hands.

Any geared motor system would need a considerable gear reduction ratio to work smoothly against the considerable torque required.
This is no simple lash-up! Not like adding R&P focuser movement with a Skywatcher motor. Or tuning to a PST etalon. Done both.

In fact I imagine a worm/wheel gear might be a much better approach. This could be incorporated for manual adjustment.
With the worm mounted on an extended shaft. Brought back to a manual adjustment wheel near the eyepiece.
Lots of gear ratios are possible but there might be an optimum for reduced manual effort without time consuming winding.
Availability of suitable commercial worm/worm-wheels? Dunno.

All these ideas are off the top of my head without deep analysis of effort:ease of use ratios.
Do not underestimate the remarkable effort required to turn the Lunt pressure drum! Grr? 😠

 

 The relatively smooth interior of a GRP dome provides rather more cat swinging space. Than any design with interior ribs and a deep base ring.

 I had to give up all hope of a proper dewshield on my 7" f/12 in the 10' dome. The same problem at the tail end. When the 2" Lacerta solar wedge overlapped the base ring at certain times of the year and modest solar altitudes.

 Raising the mounting of a classical refractor may bring the dewshield arc more concentric with the dome. Worth checking if dome space is at a premium.

 A GEM mounted refractor has a complex, oval aerial sweep. Because it is reversed to each side of the mounting when crossing the meridian. I had to be very careful when carrying out a reverse. Not to hit my imaging desk with the elongated filtration unit of a modified 6" refractor. Fortunately I remained in the dome so could carefully monitor during a  slew. Remote imaging would probably require multiple internal cameras. To avoid cable snagging and obstruction problems.

 Many drive systems cannot cope with manual adjustments to the telescopes. The tracking will be completely lost. Without a reset to the nominated parking position. There are of course expensive mounts which allow manual slews. 

 These are all irritations one would never realise without direct hand-on experience over time. Which is why I was building a 14'/4.3m GRP dome. To have more room than the 10' dome provided.
 

10 hours ago, tomato said:

I have two 6” refractors side by side in a 2.2 metre Pulsar dome. The aperture is wide enough (just) for these.

 

Is "alien technology" allowed in this thread?

I built my own 10'/3m plywood dome on the ground.
Then rebuilt it up on top of a two storey DIY observatory. 

My solution to wind lift was to have disks on top of each of the eight rotation rollers.
If the dome ever lifted it was restrained by the disks overlapping the base ring.
No hold downs to remember or forget.
I used a friction roller and crank to turn my heavy dome.
Don't build a plywood dome unless you are a skilled boat builder.
They leak at the joints!

A WHITE fibreglass dome would be preferable to avoid heat gain.
Particularly if you get tempted by solar. Don't go green for appearance!
The GRP temperature will rocket in the daytime for solar!
I was building a green 14'/ 4.3m GRP dome until recently. Hot!

Get the biggest dome you can afford. 10' minimum for a 6" refractor. Secondhand GRP? Why not?
Refractors and SCTs make most sense with a dome.
Most domes have high walls. Dobs are like looking up from the bottom of a well.

There is nothing quite like knowing you can go out and find everything set up.
Switch on and start observing and/or imaging.
This lets you do far more of it. No mental hurdles to overcome.
Sky a bit doubtful? You can go out for a few minutes to try your luck.
If conditions are unsuitable then close up and go back indoors.

A dome is the cosiest observatory. Wear warm clothes if it is cold.
Every astronomer should own a duvet jacket.
Get a pair of salopettes for winter from a charity shop.
A good pair of fur lined boots can be quite cheap.
Don't stand on bare concrete or slabs. Put down a mat or rubber tiles.
Sit down if you image. Put a warm cushion on a comfy, patio chair.

Another great advantage of a dome is the hedgehogs can't get at you!

Correct orientation of an image helps to confirm unique details without complex image handling software.
Just to match the 99.9999999999999% of all the other correctly oriented images.
Every image is a very brief moment in the history of a highly active body like the sun.
One is very likely to capture interesting features like flares, proms, spot changes, entrances or exits or even transits.
Which NO OTHER IMAGE managed to capture at that very precise moment.

Excellent images! 

Here be dragons! ☺️

3 hours ago, Ags said:

Aaaah, but was it the same sun? 😂

Objection! Argumentative!

14 minutes ago, Roy Challen said:

Nice one! Weird isn't it? Most of us dislike artificial objects interfering with our views of the sky, yet I do like a plane transit 😄, I also saw one yesterday. Maybe it was the same one?

I think it is very unlikely with your registered locations being so far apart. The sun is very small on the sky.

1 hour ago, scotty1 said:

You must of felt very proud and excited when you finished building such a grand observatory. 

Is there going to be another observatory to replace the dismantled one? 

Thanks, but no new observatory is likely now. I'll explain why. Because it may help to guide other builder's decisions. I have years of hands-on experience at this.

My own back garden is no longer fit for solar imaging due to excessive tree growth. Only a narrow angle is clear around the south and the house lies on that path. A hot, tiled roof ruins the seeing! The only cool roof is white. This limits the choice of covering materials and is not usually considered very pretty. White corrugated cement sheeting and white glazed tiles are sometimes used by architects. The rest of us are unlikely to get away with it!

Shelter, from the sun, for the imager themselves is vital IMO. Sitting for hours exposed to the hot sun is very, very unpleasant and even dangerous. [Cancer & heatstroke.] A dome can provide vital shade but sets tight physical limits on size and wall height. I could hide behind my massive mounting, pier and instrumentation. This required I sit at an imaging desk with my large monitor[s] fixed to the huge pier and facing north. Some shifting about of my chair, to avoid the direct sunshine, was still necessary at certain times of day and year.

The size of my 6" refractor, with H-alpha filtering extensions, sets a minimum size for any permanent shelter. I am no longer able to lift such a heavy and unwieldy instrument onto a mounting unaided. Which means permanent mounting of the instrumentation. Even an E-W parking position set tight limits on dome size. Once the scopes are pointing high, the large swept radius must lie within the dome's supporting structure. [DIY dome ribs and observation slit ribs usually extend inwards.] A smooth interior is fine. If the structure is stiff enough. Which requires thicker and much heavier GRP. Or a perhaps a GRP-foam-GRP sandwich. I would never choose any other colour but titanium white for an observatory. Green painted plywood and self-coloured GRP absorb considerable heat. The heat is built up inside the dome. Then escapes through the observation slit and ruins the seeing.

Raising the solar telescope above the sun-warmed ground helps improve solar seeing conditions in the heat of the day. Grass is fairly, thermally neutral. Tarmac, dark stone, metals and painted surfaces anything but! I spend hours wandering around with remote sensing thermometers and IR cameras checking different surfaces. White is usually good. Depending on its absorption and emissivity across the entire solar spectrum.  Draping white tarpaulins or shades externally can be helpful but are usually wind intolerant and look very untidy.

A smaller, roll off [roof?] housing for the telescope and separate shelter for the imager would work. Having a continuous view of the telescope is vital IMO. To avoid cable tangles and obstructions. The camera end of the telescope can swing very low when the sun is high. Causing unforeseen obstructions on the imaging desk and furniture. Even though my dome was 10' [3m] in diameter and the walls my nose height it set severe limits on freedom of movement. I would often be tracking the sun continuously from just after sunrise to local sunset.

The cost of commercial domes rises rapidly with size. Making DIY the only way forwards for many of us. Which means the risk of failure is very high indeed. Unless one has lots of DIY experience. Long term weatherproofing is very difficult for most amateurs! Tar felt roofing is fairly foolproof but absorbs enormous amounts of heat. It is also very heavy!  A Peter Drew, barrel shaped 'dome' in aluminium would be my first choice. If I had my long life all over again.

Thanks. For some reason I wasn't notified of your response until today.

Living in fear of a demand for removal [by my very tolerant wife] guided my selection of materials and construction methods. My two storey domed building is half hidden by the house but still visible from certain angles. There are no near neighbours with clear oversight. The height was required because of constant tree and hedge growth. I was careful to stay within the very lenient planning rules for garden structures.

It was quite magical to do my imaging up there for hours on end. My wife preferred my being nearby. Rather than many miles from home on yet another cycle ride. The front garden is rather too small and limited to allow a reasonable sized [domed] observatory. Solar imaging would be reduced to only a few hours in winter. A white dome would also be highly visible to my neighbours and the distant road.

Light coloured, round objects stand out like a sore thumb in the mostly green countryside. While a white caravan can go completely unnoticed. I have erected quite small, TV dishes in the front garden and could easily see them from over 200 meters away. I just didn't want to draw attention to my hobbies. Nor cause an accident. When some motorist was "rubber necking" at my distant observatory. Which I soon painted green. After an exploratory coat of white primer. The primer was a serious mistake and caused the high quality timber protection paint to peel rapidly.

I have had a serious "man cold" for the last week or more. So deconstruction has been on hold. I have now discovered I have a heart problem. So must be very careful with heavy work. Normally I would have worked for hours. Like a very fit person in my 20s. Just as I have done all my life.

Dunno. All I can see is worms.  ☺️
 

3 hours ago, Ibbo! said:

Yes you can 🤣

Nice! Amazing proms!

Is a dog's breakfast visible in H-alpha? 🤔