Rusted

Judge them by their driving behaviour. They cannot risk easy discovery. If they can drive well then they are quite clearly alien. Though probably not transparent.

Only when they stare back at you! Spooky!

The enemy of handheld [or rested on walls] telescopes is magnification. The "wobbles" putting it in rather technical terms. With increasing aperture, the weight and length soon get out of hand. [A deliberate pun.] In the absence of commercial sky hooks you then have a problem of seeing anything! [At all!] Just take my word for it. There is a space race for larger spotting scopes for birders, hunters and wildlife voyeurs. The lenses and bodies get heavier with each increase in lens size. Which means a heavier tripod. Which needs a friend, Sherpa or slave to carry it all for you. Binoculars are available in many different sizes but nobody ever wants to carry them far above [say] a 40mm aperture and 8x. The sweet spot! Be very careful what you wish for. I have spent decades looking at laterally reversed images but I still couldn't eat a whole one. A "proper" terrestrial prism is essential to the full enjoyment and remaining sanity of the observer using any portable telescope. These prisms have n even longer glass path length than a common star diagonal. So choose your telescope carefully and wisely! Or be prepared to saw big chunks off your end. With advice from your fiends on SGL of course. 😉

For all our faults [well yours, not mine] we have been fabulously lucky to have survived this long. Big, fast, falling objects, too near to astronomical cataclysms, misogyny, pandemics, childbirth, advertising super-saturation, mass superstition, THE 1%, survivable temperatures, radiation, vulcanism, war, earthquakes, drugs and alcohol, volcanoes, inbreeding and interbreeding, climate change, starvation, flat feet, nuclear armaments, dirty water, tin pot dictators, dyslexia, exercise avoidance, UV, genetic defects, monarchy, race extinction, pop culture, obesity, trash foods and drinks, daytime TV, predators, AI, LBGT, Disney, gerrymandering, etc. the list is endless and I have hardly scraped the bottom of the barrel. There is bound to be more to come that we can hardly imagine yet with our myopic superstitions filtering every thought. Somehow we survived with compound interest. We are now so numerous that we are wrecking our only trailer home as we surround ourselves in toxic disposable garbage and take potshots at passing planets. All to satisfy the ego of billionaires, Dumb and Dumber to help their ratings on Junior Twatter. Every single organism in the universe has to overcome the same list and far more and survive to tell the tale in a recognisable language which allows learning from silly mistakes and to achieve iterative progress. Despite the absolute proof that we and they haven't a clue what we or they are really doing. And do so again and again and again and again at every single extinction hurdle which presents itself. Having survived into sufficient numbers to manage really large projects. They must develop FTL or [far more likely] astral projection to spread their own religion of crop circles delivered by black cheese wedges and silly, flying saucers. Well, I don't know about you, but I really don't fancy the look of yours! Don't you have anything with fur and pointy teeth? I could really do with a nice change.

A child proof pier? Whatever next?

There's nowt wrong with Cleethorpes! Mind you, when I were a lad on the herring fleets we'd set sail for Greenland whether we needed to, or not. 🥶

What Peter and Gina said. Choose a deep, rectangular cross section for a bent pier. NOT an I-beam or U-beam which both twist far too easily unless physically restrained. A deep box helps by increasing the moment of the beam perpendicular to the applied loads. Stiffness increases as the square of the depth of the beam or hollow rectangular tube. Which is why floor and roof joists are always set on edge. Not laid flat. Nor made square. Which is wasteful. Round tubes and poles are far more "springy" because they have so little resistance to bending. Moreover, the "leverage" of any offset telescope mass is always trying to pull the pier [or tripod] over at ground level.

I have some direct experience in this matter. My 10' dome is raised on a timber building to second storey height. The massive, pyramidal timber pier is almost immune to vibration. I even had my computer desk directly mounted on it for a while. I have just removed my 7" f/12 refractor from the massive GEM mounting. This was because it was catching the wind through the observation slit in winter. Not even a dewshield to act as a spinnaker and the cell was a couple of feet inside the dome surface. Just the bare objective cell on a long, smooth, 8" Ø metal tube. Early morning solar imaging in the three warmer months avoids the prevailing south westerlies. As the day progressed the slit and telescopes move steadily westwards. Beyond lunchtime was usually a problem despite the meridian flip. [When the telescopes were now pointing into the wind instead of sideways on.] The solar seeing conditions in windy weather are rarely much good anyway. But the general lack of sunshine means I like to try whenever it is shining. A bent pier is just one-legged tuning fork. A perpendicular dropped from the centre of mass must pass down through the pier into the ground. With a GEM that is the crossing point of both axes. Even an offset mass, like a typical fork mounting and hefty OTA [SCT?] will place serious asymmetric loads on a vertical pier. Asymmetry means easily induced vibration to every touch, footfall or breeze.

Hi, We had a sunny day on Saturday 4th Jan. Just before lunch the violent, thermal shaking calmed a little, but not completely. Still struggling with the new version of iMPPG followed by PhotoFiltre7. The usual 6" f/8, internal D-ERF, GPC, PST mods, ASI174. The ring of filaments above the bright AR is interesting. I was seeing similar detail on the monitor at the time.

I liked BBC Basic. You knew where you were with that. It was great fun finding typos and errors in formulae and worked examples in optical, ray tracing, classical text books by the "Great Masters." And false starts in astro magazines where the writer changed the exotic glass and prescription between printed articles. On which glorious careers later depended. All done with countless, nested brackets. No matter how much you doubted your own software it always proved right in the end. Who needed OSLO when you had Basic? Now where's that smug smiley with the long white beard?

Software gremlins may eventually be our only defence against AI and The Terminator. Not theirs. Ours! I have determined that the imaging learning curve is overhanging, covered in dark matter and completely without foot or handholds. Every time you fall off you have to spend twice as much, as before, just to get back to where you last fell off. Meanwhile, the experts not only started with several lifetimes of natural skills and sheer genius, but are pulling ahead at just above light speed.

The obvious improvement in colour correction was once the exclusive sphere of the triplet. However the introduction of special ED glasses has reduced their advantage. When I dabbled in geometric ray tracing one could obtain 1/10th as much false colour with a triplet. But, then only in comparison with a doublet of common glasses like BK7, F4 at longer focal lengths. The triplet APO still needed very exotic and expensive glasses at that time. e.g. Roland Christen's early 'AP' APOs. Special glasses are now much more widespread in larger aperture blanks thanks to the Chinese popularising affordable "short" APOs. Not to mention binoculars and spotting 'scopes. None of which answers your question. Triplets do have the reputation for much slower cool down. [As already discussed above.] Peter's mention of mirrors is certainly true. The ultimate "planetary" telescope in amateur sizes is/was probably still an optimised Newtonian of 12-15" aperture and longer focus. However, the corrective elements now available to combat coma are even allowing short focus, large aperture telescopes to produce superb visual images. But only in excellent seeing conditions. Like Florida? Or at high altitudes. Yet another red herring to avoid giving a direct answer?

If you are incredibly lucky you may find a secondhand lathe ex-education or from a small business going bankrupt. I picked up a good quality, British, tool room lathe on its original cabinet + tooling, ex-uni for a couple of hundred quid, but that was ages ago now. The floor pillar drill expense and wasted space was met by shelf mounting my big pillar drill into sturdy 24" deep shelving on thick ply + support pillar underneath. This replaced cheap 12" shelving with steel shelves [which always collapsed under their own weight] and holds lots of stuff in big, but shallow, 4" deep, plastic tubs from IKEA. Downside is the inability to stack these trays without using the lids. Which means double handling to reach the lower storage trays. It ought to be made law that storage tubs stack by reversing them by 180°! I moaned for years about the usual deep storage tubs before I found the IKEA. Most of my old tubs were mostly fresh air. Or far too heavy to lift! The trick is to fill all the fresh air on one wall right up to the ceiling. This leaves space on the rest of the floor for woodworking machines [saws] on wheeled stands/cabinets. These can be nested and/or packed away compactly under deep shelving/work benches when not in use. The investment in decent kit made it possible to complete my two story, 10' Ø trapezoid dome at a fraction of the cost of a commercial plastic shell. Nobody did one big enough for my 7" f/12 refractor for less than the cost of a small car.

Building a replacement for my 6" solar H-a scope. With better parts now I know what I need from months of direct, hands-on experience. H-a solar imaging has become so much a part of my daily life that it is well worth investing more funds. Still small change compared with commercial offerings in this aperture. The plywood dome already needs a strip and repaint. Or re-covering with something more waterproof. Building a shiny, aluminium, trapezoidal dome would be good from a thermal/waterproof POV. Just too visible from a distance. When I'd rather be camouflaged. Like a big tree!

2x WO Barlow of last dregs of the 'pylon' prom before the sun sank below the roof. Seeing was awful all day! But at least the sun shone. I thought it had forgotten how to!

Yes. At about 10.00 o'clock on the NE limb. Ignoring chimney total eclipses of the sun!! Pylons? Here you go:

Even after 17 hours torturing the final image on the iMPPG rack: See it and weep! Not even a pylon for added interest! 😉

You don't get bragging rights from being north of the M25 any more. Not since the fall of Hadrian's Wall.

You can nip round and fell my neighbour's trees if you have a moment to spare. Gone 11am and the daft things are still rocking back and forth in front of my rare H-a sunshine. Grr?

I haven't read any science fiction in 50 years so must bow to your obvious expertise.

Well done. I have no direct experience of CF. Only glass fibre and cloth with polyester resin. It would be humanly impossible to make your tube any uglier than mine. I was working on the outside!

iThey only need to expand access to the Internet because they have already achieved total, devastatingly invasive, advertising supersaturation with the presently available, hideously involuntary, customer base. Income, versus expenditure, is now falling like a world destroying, mega-meteorite. Though, unfortunately for most of us, not one of the Daily Express, imaginary variety. Like every other human endeavour before it, iThey has greatly exceeded the sustainable resources available. So that full desertification is rapidly approaching their balance sheets. Leading to total, global, panic and financial collapse. Before long, institutional investors will begin to realise that there really is nothing on the horizon to replace the critically damaged, advertising supported, expansion model. iThey values are entirely virtual. With nothing to convert into hard cash when the downturn comes. iThey is already running on borrowed time. Note how all the smart entrepreneurs are running with their cash while they still can? Just as smart robots are about to replace most forms of manual employment, it is highly likely that General AI will soon begin to decimate iThey workforces. Like a fleet of vast, burning dirigibles, once the gas ignites, it will quickly spread between them. To reveal there never was anything behind the paper-thin facades. Except empty hyperinflation and a heavily tattooed, fake skin. Decorated with tasteless, pixelated, pop-up, in-yer-face, advertising banners aimed squarely at the inter-lektule "lower orders." iDon't believe it? Well, if it looks like an iBargain, too good to be true, then it very probably is. Creeping iCynicism will soon make a global, Windoze, DOSS attack look more like a dodgy case of Monday Morning, man 'flu! 🥶

Isn't the same multiplicity our strength rather than a weakness? We don't usually allow a complete monopoly in any one thing. This means we can usually survive a critical bankruptcy or factory fire. Competition for survival, within any commercial sector, usually ensures progress. It usually means lower costs even if it takes time for trickle down to occur to the masses. There must have been some really leaden feet because so many businesses went bust. Communism was formerly the prime example of industrial weakness through deliberately restricted choice. Yet China took several centuries of Western technological progress and ran with our balls. Now you find Chinese names on a great many scientific and engineering breakthroughs. They produce more engineers and scientists than the rest of the world put together. Humanity constantly invents new things because it provides adequate education. It seems inevitable as previously powerful dampers, like religion and gender, are removed. Just imagine what "we" can achieve when Sub-Saharan Africa is freed from our historical yokes. Given a proper education, fed properly and relieved of the daily theft of their resources. Freedom to invent and improve is often despite crippling restrictions like hunger or gender. Petty monarchies, barons and warlords no longer control the freedom of ordinary people to imagine our future.

Without Gravely Blighted, Denmark would have no weather at all. We watch the UK weather to see what you are sending us next. Will you have to stop doing it when you are outside the EU?

I invented the universal, "girder" suspension fork for bicycles with a generous, 7.5" travel. Unfortunately it was just a geometric improvement on the existing design of decades before. Most suspension bicycles now have short-lived and/or expensive, telescopic forks. Then I invented the self-supporting, binocular steadying device for astronomy. It relied on two shaped bars with counterweights behind the wearer's shoulders to balance the weight of the binos. Sadly it only worked over a very small vertical angle and nobody would want to carry more than twice the weight anyway. Then I invented the "tunnel" tent with arched fibreglass, self-supporting poles. It looked just like the mountain expedition tent offered by Blacks of Greenock at the time. I can only assume they were mind readers.