Zermelo

I have 1.25" x2 and x3 models from VisionKing and Opticstar (can't remember which way around) that I believe to be optically the same as the ES. One is quite a bit cheaper, new, than the ES; the other, not so. Second hand is possibly a bigger gap, as the ES probably hold their value more.

This is a good site for this kind of thing: https://www.heavens-above.com/

If you were working at a site where you could make noise, this would be gloriously old school. If you weren't lucky enough to have an assistant, there might be an opportunity for astronomy-literate stenographers at the other end of an Internet connection, somewhere in the world. I know a tech solution isn't right for everyone, but I have found the Microsoft Swiftkey keyboard in Android to be quite effective in predicting my next words, when I'm writing up observations in SkySafari. It is a bit circular, and re-enforcing: the more often I type "a little less scatter seen in the Morpheus 6.5mm", the more it will suggest it. I control the brightness with a combination of screen reddening and a physical filter made from a spare phone case and red gel sheet. At very dark sites, I might need more.

And here

They are four-element telecentric multipliers, which have some advantages over telenegative Barlows. Televue Powermates have the same design. https://www.cloudynights.com/topic/719810-a-4-element-barlow-is-it-even-necessary/

Stop it, right now. I can resist anything except temptation, and eyepieces.

I don't like the Tak's twist lock either, especially now that I have a Baader quick lock to compare it with. It's surprising how much the barrels of different EPs vary.

I agree. I would say there are two effects I see in globulars when they are on the limit of resolution. The first is the scintillation that @John describes. The second is a graIniness, a grey area with a texture that just fails to show individual stars. Personally, I find these effects to be as pleasant as a resolved cluster. I don't see the same effects with open clusters, with the exception of one or two that are small and dense (such as the Wild Duck).

https://xkcd.com/2844/

If they can do it, why can't we? https://www.space.com/chile-new-standards-fight-light-pollution

Snap. The 1.25" prism is also my only piece of Tak, and likely will remain so.

Aperture fever strikes again. It sounds like a marvellous experience, Rob. Did you see much colour in the dobs?

No, you're not:

Yes, to clarify my previous comment, I fitted a 2" visual back to my Skymax, but not a new focuser.

You might want to start a new thread. I can't remember if it was a Skymax you were talking about. If so, there will be some vignetting (dimming at the outer edge) if you use some eyepieces, though I've not noticed with mine. You might be interested in: https://stargazerslounge.com/topic/336529-sky-watcher-mak-127-visual-back/#comment-3662339 https://stargazerslounge.com/topic/356717-sw-127-mak-ota-with-2-focuser/

True, it has "only" five elements. Svbony did market the more complex 15mm and 18mm too, though I haven't seen them for sale recently.

I'm not sure if Svbony market two different zooms with almost the same range? The 7.2-21.6mm looks almost identical to the OVL Hyperflex and others (but quite a bit cheaper): But then there also seems to be a 7-21mm that looks different:

Another eyepiece for me today. The SV190 is Svbony's version of the 10mm UFF. I'd noticed the price creeping gradually downwards over recent weeks, but hadn't been tempted as I already own the Celestron version (Ultima Edge). And that one has been a bit squeezed out by my 10mm BCO and 9mm Morpheus. Then last week I saw it offered on eBay for £16 posted, and thought it might be worth a punt, to see if perhaps I could use it with the Ultima as a binoviewer pair. It even came with a frameless IR/UV cut filter, though that will go straight into the bits and bobs drawer until I think of something to do with it. And here it is with the Celestron. Only their mother could tell them apart?

I'll be interested in your findings. It's the one I need for the set, too.

An excellent writeup, what a great evening.

Well, for once the forecast held: and so I managed a short session this evening. As well as a new moon, one of my neighbours was away too 😀

Just a couple of hours with the Mak tonight. It was noticeably colder than of late, but not uncomfortable so. Transparency was good, apart from the occasional cloud. With no moon, it was about as dark as it gets here. Seeing good/average. I was still interested to see how my cheap Svbony 9-27mm zoom compared with its more expensive companions. It did well again. At 9mm, it showed the double Gamma2 Delphini crisply, though not quite as tight as the Morpheus 9mm. However, the yellow/blue contrast was noticeably more distinct in the Svbony, while scatter was the same in both. On the rather dim globular M72, I was surprised to find it, showing obviously (though faint) in the Svbony at 27mm, despite the background being light with the large exit pupil. The Morpheus at higher magnification did manage to show some granularity, which the Svbony at 9mm could not. The more accessible glob M15 showed some stars flicking in and out with both the Svbony and Morph 9mm. The view in the latter was better, though not dramatically so. Saturn showed well in a Morpheus 6.5mm, with a clear northern belt, Cassini division just visible at the extremities, and satellites Titan and Rhea. The view in the Svbony at 9mm showed good contrast, and - surprise - Tethys was also visible with averted vision. It was also seen in the 9mm Morpheus, but there was little to choose between them. Jupiter was a bit disappointing by comparison; NEB and SEB were obvious, and two further bands very faintly seen, but no real detail in any EP.

LIDL have one on sale from this weekend, as part of a space-themed offering. No idea what it's like, other than the pictures in the listing. https://www.lidl.co.uk/p/space-themed-projector/p10008138

It's already been done... https://tardis.fandom.com/wiki/Voga