Peter Drew

It could be that one of the three lens elements has become decentred, if so, tilting the lens cell won't cure the issue. 🤔

Close, but no cigar. 🙂

I think to be on equal terms we would have to meet aliens somewhere halfway across the galaxy, not here. 🙂

A 8x40 might be a good compromise. The weight and easier to hold steady advantage can outweigh the reduction in aperture disadvantage. The reduced aperture for daytime use will not be noticeable. 🙂

I don't think the third party supplier of corrector plates for SCT's offer a 14". A return to Meade is likely to be the only way forward. Regarding the matching debate, I'm convinced that the only variation is the small secondary, it being the component best suited to figuring. The procedure to produce the corrector plate almost guarantees that they will all be similar enough to be transferable, their optical effect, although essential, is very weak. Similarly, it would not be practical to aspherise a spherical primary, departures from a sphere can open up a large can of optical worms. I think it is far more likely that Celestron have a large selection of secondaries and if any matching is involved, this would be the component. I also think that Celestron are reluctant to supply single correctors as they need some expertise to set the complete system up. I made several SCT's in the past and watched at first hand the difficulty and time spent in producing the optical components from scratch in house and there is no way Celestron could afford the time at their price point. 🙂

Well I was snug in bed confident that someone would have a snap of the event, so thanks to all concerned. 🙂

Pretty sure it will be a field star. Other Jovian moons can be detected but call for very large optics and most likely imaging.

Lens element spacings on budget items are usually calculated to provide the best compromise between spherical aberration and chromatic aberration. You can alter the spacing to improve one at the expense of the other, no free lunch!. Bear in mind, little or no special figuring will be applied although with mass production you may strike lucky. 🙂

I remember the 15" D-K, not easy to get magnifications much less than 1000x with a 15" Cassegrain!. I wonder where that telescope is these days, it was for a time in the care of Luton AS. 🙂

Just paint Takahashi on the tube and it will look enormous to some people. 🙂

Star testing is very valuable for determining the presence of broad optical defects such as collimation, spherical aberration, astigmatism and mechanically induced distortions. The finer points and marginal assessment call for significant experience. 🙂

Not focusers, but I have made similar action components for other purposes. It's one of those designs that look good on paper but which can be quite difficult to implement. Unless there is a decent length of axial support, multi component bearings have a tendency to "crab" if the motive force is not on a central axis. 🤔

This is what I was going to suggest but didn't realise you had suitable equipment. 🙂

With the tripod upside down and the spreader plate not fitted, try splaying the tripod legs out as far as each will go. Then fit the spreader so that it is touching all three legs and then tighten the nut. 🙂

Regardless of which way up the spreader needs to be I have always found that that once the central nut has been tightened, if I jiggle a couple of the tripod legs a little I can usually tighten up the nut a little more. 🙂

At one point those were the only telescopes I had access to, most of my seaside pocket money was spent on them. 🙂

Despite the advances in technology and vast sums of money spent, naked eye is still the most successful at detecting alien activity. Just look at the number of UFO's etc that are reported. 🙂

Although not a professional I have resprayed many OTA's with a satisfactory finish. A few tips, rub down any original gloss finish to give a matt keying finish for the new coat, use an appropriate primer, a quality can of top coat and follow the instructions, specially shaking the can sufficiently. I have used large cardboard boxes as spray booths and hairdryers to gently warm the cans and items to be sprayed if cold weather. Try a sacrificial item for a bit of practice. Good luck! 🙂

I doubt it. 🙂

It's relatively easy to make such a low power binocular with angled eyepieces. The one I showed on CN took me an afternoon to make using odds and ends apart from the wide angle eyepieces. It would be even simpler to make one from two RACI finders provided that you were content to have them fixed at the base magnification and your personal IPD. The latter specifications can be addressed with a more sophisticated arrangement. The views and viewing comfort are excellent. 🙂

Fixed magnification and straight through viewing, no thanks! 🙂

I've seen this just once in all my years of interest. It takes an uncommon sequence of conditions, well captured. 🙂

Remarkable professional image, not quite as dramatic on the GONG image which is more representative of what we amateurs see. 🙂

I agree with Mandy D. I think you would be better served by a larger diameter drive "pin" and a multi-stage reduction. The friction drive on my 8.5" refractor mount has a 11" wheel driven by a 2" driver. The driver is driven by a worm and worm wheel, itself driven by a geared motor. 🙂

I wouldn't get either to be quite frank. I think a Skywatcher 130 would be a better bet. 🤔