Louis D

The 31mm Luminos is going to be much better corrected across the field than say a ~30mm 2" eyepiece of the sub-$100 wide field variety. There have been reports of kidney beaning or edge of field brightening under certain conditions, but these are probably preferable to vast edge of field astigmatism present in cheaper eyepieces. The used price is about typical for these; so you could probably sell it on if it doesn't work out for you without losing much, if any, money on it.

I've been using one with a 25mm spacer ring in my f/6 Dob. It corrects about 99% of the coma in the outer field for eyepieces focusing with 5mm of their shoulder in this configuration. Perhaps in a faster scope you'd need to be more precise with the spacing. Just replace the thumbscrews that came with it. One of them sheared off in the holder tube on mine, and I can't get the remains out. The screws are made of pot metal.

I guess it shouldn't surprise me you like binocular astronomy. 😉 I picked up Crossen & Tirion's Binocular Astronomy back in the 90s (first edition) and still have it. I went through it and used the excellent charts at the back, but I still longed for a telescope. Once I got my first Dob, I went crazy on astronomy. It was the increased image scale and light gathering that did it for me. I do enjoy sweeping the night sky at low powers, but I use 2" eyepieces in short focal length ED/APO refractors instead of binoculars. I might try to make one of these binocular observing chairs someday, though:

During naked eye observing, you'll notice star fields will look more pinpoint wearing eyeglasses if you choose to get a pair. I don't know about Norway, but in the US, there are multiple, affordable online eyeglass makers if you don't feel like splashing out too much money just to correct minor astigmatism in one eye.

Yeah, that's way out of focus. Next time, turn the focus wheel(s) forward or backward as much as needed to minimize the size of that white spot. If you center it at best focus (smallest and sharpest image), you should see Jupiter's main equatorial belts and its 4 Galilean moons. It should look a bit as below through your scope: Of course, it will appear tiny to your eye:

Mostly better lens polish, coatings, and stray light control. Most folks positively compare the Leica ASPH to the Pentax XW and Delos lines for sharpness and contrast. There's also a Zeiss zoom with a wider range that is also well received for similar reasons, if just a bit behind the Leica image fidelity-wise.

Right there with you even though I'm a few years from retirement. Youth is wasted on the young. They (whoever they are) keep telling us this or that will extend our lives X amount of years. Do I get to choose which X number of years to tack on, or do I just get X more elderly years? I think back to 30+ years ago and marvel at what I used to be able to do in a single day. It makes me tired just thinking about it. I used to think, "When I'm retired, I'll be able to do all these things I've never had time to do". I just didn't count on being old and decrepit at that time. Getting old sucks (pardon my language).

I can see where a Barlow when coupled with low cost, long focal length Plossls could be a good solution, especially if you need to wear eyeglasses due to eye astigmatism. The only issue I have with some of the long focal length Plossls is that most greatly recess the eye lens, negating their long eye relief. The 15mm and 20mm Svbony UWA 68 degree Expanse-type eyepieces don't suffer from kidney beaning, just the 6mm and 9mm versions. The 20mm is great Barlowed in my binoviewer. I was using a pair of them to observe Jupiter Tuesday night. Even without a Barlow, they should do well in an SCT.

The two piece tube cap can be used for that, but you'll drastically cut down your potential resolution by masking your aperture. It can be used to sharpen up the image by making the scope have a longer f-ratio and by making the system unobstructed if it is an off axis opening and you place it between spider vanes. It can also be used to allow for use of a smaller solar filter. Try it and see, what's the worst?

Is your scope the National Geographic 76mm Compact Reflector Telescope?

When asked if I'm free on a certain day or evening, I always say I first need to check with my social events coordinator. I just go where and when I'm told to go. 😊

Only the two negative/positive design versions suffer from kidney beaning. Those would be the 6mm and 9mm versions. The 15mm and 20mm versions are straight positive designs like a Konig variant, so they don't have that issue. Kidney beaning tends to happen mostly in negative/positive designs or when pairing a positive only eyepiece with some Barlows in my experience. Of course, without the negative section, they don't perform so well in faster systems. Even with the Barlow element on the BV, I didn't notice any kidney beaning with the 20mm Svbonys. Since I was able to pick up the pair for under $50, I was willing to roll the dice with them. I'm glad the Morpheus pair worked fine for you. The added weight and lever arm can be an issue as you say.

Around here in Texas, we're usually well south of the jet stream, so our skies are often very stable (it also leads to prolonged droughts). If you have the aperture, 100x to 200x is cruising and 350x to 400x is quite usable. It's part of the reason big Dobs are popular in these parts because aperture is really what limits resolution, not the atmosphere. Of course, these same dead calm conditions are perfect for mosquitoes for a few weeks during our long summers after the infrequent rainstorms (I was batting them away last night despite our last rain being 2+ weeks ago). 200 miles west of here, and they are no longer much of an issue because of how arid it gets that direction (away from the Gulf). Having lived in New York state for 6 years near NYC, I totally sympathize with your weather predicament. I couldn't realistically take up astronomy there at all because of it. I simply looked at lunar eclipses and planetary conjunctions with binoculars while living there. My hat's off to anyone in the UK trying to stargaze.

Watch out for the space left between them for your nose. I tried it with two Astro-Tech AF70 17mm eyepieces, but my large nose prevented me from comfortably using them. I would have had to approach them with chin tucked downward and looking through the very top of my eyeglasses to use them. I experimented by pairing my 17mm with my 13mm in my BV, pulling the shorter one outward in its holder to mimic having a a pair of 17mm eyepieces. If their tops had been sufficiently tapered, it might have worked. Ultimately, I went with narrower, simpler 65-68 degree designs that perform well once Barlowed by 3x to reach focus. Last night, I used a pair of 20mm Svbony UWA 68 degree eyepieces to view Jupiter for 1.5 hours. They were comfortable, sharp, contrasty, and displayed no ghosting even with super bright Jupiter. The long eye relief even allowed me to hold filters between my eyeglasses and the eyepiece (one side only seemed to work best).

What focal length? It's dependent on the field stop of the eyepiece, not the AFOV. Pretty much any eyepiece with a FS of about 26mm or less would not vignette since that is BM2's clear aperture. That covers all but a few widest TFOV eyepieces like a 32mm Plossl and 24mm Panoptic/ES-68/APM UFF which have ~27mm field stops. The widest 82 degree Nirvana in a 1.25" barrel is the 16mm which has a 21mm to 22mm diameter field stop, so it shouldn't vignette. However, since it is a negative/positive design, we also need to look at the field lens diameter which is 25mm because we don't want to block the edges of it. Again, it is less than the BM2's clear aperture of ~26mm.

Reminds me of putting a car in a garage. I'm picturing someone on the crawler with the VAB remote control to open the doors.

Your mission control must be contained in a totally mod, mid-century mansion as in the video as well. 😉

Artemis 1 is pretty nimble after all. 😉

I'm picturing SpaceX moving from Boca Chica to a volcano and Elon Musk getting a high backed chair and cat:

I swapped it for an unenhanced, shorter clip. I have no way to know if it's blocked over there as well.

Alright, as a Yank, I had to look up these references since even us oldies are only vaguely aware of the Thunderbirds shows. I found the below clip to clarify your references: If y'all do launch for the moon or Mars someday, we'll hold you to launching from beneath a retractable pool. 😁

If you already swapped a Delos for an XWA, why haven't you swapped the 22mm NT4 for a 20mm XWA? You'd have some extra cash in your pocket as well.

For more on my Jupiter observing tonight, check my post below:

I was out tonight between 1am and 2:30am with my 90mm f/6.6 TS-Optics Photoline FPL-53 Triplet APO. Jupiter was nearly 60 degrees above the horizon for me, and the atmosphere was super calm and clear thanks to a front that moved through Texas Monday morning. I used my Arcturus binoviewer with Meade 140 2x Barlow element to reach focus and boost magnification by about 3x. I used a pair of Svbony 20mm UWAs (68 degrees) all night for about 90x. The image seemed plenty big and bright, and contrast was right at the acceptable limit, so I didn't increase magnification. The Ganymede transit shadow was very clear, although I couldn't make out the moon against the face of Jupiter. It was super neat watching the moon emerge like a pimple off of Jupiter's limb. I thought I was seeing things until I realized what was happening. Being just past opposition, Ganymede and its shadow weren't separated by very much. I then watched it completely separate from Jupiter. Next, I watched its shadow slide off the edge of Jupiter. All the while, I had a nice view of the GRS. Toward the end, the NEB had a noticeable darkening toward its center. I tried a multitude of filters to see if any improved the view. The best was a generic green filter over my dominant eye held above the eyepiece. It really helped bring out the GRS and NEB shading. Orange was the second best followed by magenta. Those helped with contrast in their own ways without overly darkening things. Blue was too dark, red obliterated all detail, and both light yellow and dark yellow (an actual #12 from OPT) were too subtle. A moon & skyglow filter did almost nothing for me. Here's the 6 piece set from China via ebay I was using most of the time. Its green filter was more useful than my green Meade interference filter tonight. It wasn't as saturated or dark as the Meade. I don't know if it's actually a #56 or not, but I suspect it's lighter. I highly recommend this ebay set, especially for the price. Where else are you going to find a reasonably priced magenta filter?

A binoviewer helps immensely as well. I had much better views when both eyes saw the same brightness tonight. A light green filter like a #56 was helpful when used over my dominant eye to increase the contrast of the GRS and NEB. It also cut down on the dazzling brightness even with two eyes. I think it also sharpened the view by cutting out the slightly unfocused red and blue ends of the spectrum due to atmospheric dispersion.