Louis D

According to @Don Pensack, Newtonian coma grows linearly from center to edge, so the wider the apparent field of view at a given magnification, the more obvious coma becomes. Doubling the magnification results in the same amount of coma because it is half as large, but magnified twice as much, so you're back where you started. This is in contrast to field curvature where low powers and wide fields really do show more field curvature than higher powers with the same apparent field since it's not a linear relationship across the image circle.

I took some images through my 8" Dob with my DSLR tonight and composited the best Jupiter image with the best Saturn image and then stretched the background to pick up the Galilean moons. No stacking here.

Do you make a habit of dangling new astro toys above a considerable drop? Are you demonstrating how confident you are of your equipment handling skills? Perhaps you're demonstrating to the new guys in the astro toolbox who's in charge? Given my sometimes shaky hands, I found those images terrifying and should have been prefaced with the warning "Some viewers may find the following images disturbing."

Good point about the secondary centering. Do you have a sight tube? If so, insert it so far into the focuser that the end of it looks to be the same size as the secondary when viewed from the peephole. It will be obvious if the secondary isn't dead centered in the sight tube view. There are generally nuts or screws/bolts at the ends of the spider vanes to adjust the X/Y position of the secondary over the primary. There is also generally a single bolt with nuts at the center of the secondary spider to adjust the Z position (toward/away) of the secondary relative to the primary. After loosening and adjusting this one, you may have to make sure the secondary is still square with the focuser again by rotating it before tightening everything down again.

Meade as a brand will continue, though attached to what products, I don't know. Brands are typically the most valuable items in bankruptcies. The question is, who will own the rights to the Meade brand when all is said and done. Meade SCTs will continue to be manufactured in China by Ningbo Sunny and their suppliers/subsidiaries. What brand name will be slapped on them remains to be seen. Ningbo Sunny is not in bankruptcy, only its US subsidiary Meade is. Because of incorporation laws, Ningbo Sunny is completely isolated from these bankruptcy proceedings in the US. At this point, the most they stand to lose is the Meade brand, but I have my doubts about that as well.

I think the #2 screw is a safety screw to keep the dovetail from sliding all the way out of the clamp should it loosen.

I use a 1.25" visual back and diagonal when using my binoviewer natively with the Mak to minimize the increase in focal length. I still come out way ahead with them instead using my effectively 3x Barlow OCS/GPC in the Mak magnification-wise.

Yes, you're pretty well covered for eyepieces. The f/12 focal ratio of the scope, along with it's narrow rear baffle, really limit the range of usable eyepieces and exit pupils. I went ahead and added an SCT thread adapter and a 2" visual back so I could use my 2" diagonal and 2" eyepieces with my Orion 127 Mak. Skywatcher is selling their 127 Maks this way on this side of the pond now. It does vignette a bit, but the view is massively wider. Here's a comparison image I took through my 127 Mak showing the difference in true field of view and vignetting with widest true field 1.25" and 2" eyepieces: It's really nice to be able to use my large stable of 2" eyepieces with it now. This is what the setup looks like:

The NPL line are considered very well executed Plossl/symmetrical class eyepieces. At f/10, it doesn't surprise me that they excel. However, they have limited eye relief and a 50 degree-ish field of view. Try the NPL in your achromat and see how it does at f/5. It may still perform well in the center, but it may tend to go blurry toward the edges. I don't know how well corrected they are in faster scopes. The BST Starguider will hopefully continue to work well at f/5 thanks to its negative positive design that effectively slows down the light cone internally to the eyepiece, allowing it to perform better. The SLVs employ a similar design, just better executed and at a higher price with a narrower field of view. Pulling it all together, the Delos and Pentax XW lines are executed to levels as good or better than the SLVs while yielding wider fields of view with just as much eye relief and excellent performance in fast scopes. The Morpheus are close to them, but come up short in a few focal lengths.

The corollary to this is that you must not look through premium telescopes with apertures significantly larger than your own scope(s) at star parties, or you will get aperture fever in short order, and that tends to drain ones wallet of all available funds.

Up until you go to a star party and look through a premium eyepiece and get hooked on the view.

If you're hunting for planetary nebula with a low power, 2" eyepiece, having a well corrected field can help immensely in distinguishing tiny, fuzzy PNs at low power from merely bloated stars due to poor field correction. Same goes for Uranus and Neptune.

My Mak is left side mounted on my alt-az, so the 3-way dovetail adapter allows the RACI to be pushed further left and lower by mounting it in the leftmost position, improving balance in altitude. I can't remember in which order I have the QF and laser sight, but I really only need one or the other in general, so I generally mount one or the other, but not both.

Mine is mounted on the back on the finder shoe via a three way extender and a finder shoe to QuikFinder adapter. That way, I can still mount a RACI there as well as a laser sight via this adapter.

@Don PensackIs this what the image erecting Barlow you remember looked like?

Are you sure these aren't using a roof-like prism assembly like the erecting eyepiece in this CN teardown? Compare images of the two eyepieces: Sky Mentor from Khan Scope: Celestron 20mm Erecting: It's not definitive, but I suspect they're similar in design. If so, here's the internal prisms:

That just sounds like poor stray light control. Not awful, just not optimal. SAEP manifests itself as full blown blackouts midway across the field from center to edge in the worst cases or simply as fleeting shadows that cause consternation because you can't get comfortable viewing the image. In both cases, slight head or eye movements in any direction (left, right, up, down, in, out) cause the shadows to dance around giving a nervous or jittery aspect to the image. Never does it manifest itself as a halo of light. It's always a lack of light.

It also depends on usage. If you do a bunch of lunar, solar, or spotting scope usage, or observe under severely light polluted skies, your pupils will be constricted, making SAEP more obvious. Fully dark adapted viewing minimizes SAEP annoyances.

I was able to see Jupiter's moons with both a Nat Geo 40mm refractor and a Celestron FirstScope 76 at a star party after getting them properly focused and on target for the owners who had brought them to get assistance. It's definitely possible to do basic astronomy with really poor, big box store telescopes. It just takes experience and knowledge to work out the issues. That, and tempered expectations of the views. I will say that the Nat Geo cheap photo tripod-type mount is the absolute worst. It's so herky-jerky and wobbly that you have to loosen up everything and keep a steady fist around the mount axes to use it successfully.

I never could get on with the Radians since they were released in 1998. They just had too much SAEP for me. I ended up getting Pentax XLs instead and continue to use them to this day. Many folks report not being bothered by the SAEP, though.

Make it a Valentine's Day gift. He'll love it. 😉

Were you watching them "burn up" through the eyepiece or naked eye? I took you to mean through the eyepiece, which would be impossible to do. I've never seen a slow moving meteor naked eye. Perhaps y'all have different meteor showers there than here in Texas. The only thing equivalent to a meteor I've seen that was slow moving was the Space Shuttle returning from orbit over Texas. It took several minutes to cross the sky.

More than likely they were satellites.

A 2" diagonal forces you to move the primary mirror forward to account for the extra optical path length of the 2" vs 1.25" diagonal. This increases your working focal length and contributes a bit of spherical aberration to the image because you are no longer at the optimal, design focal length. Both effects are minor for most folks visually. There are quality 1.25" diagonals from GSO and others out there. You're never going to get truly wide fields from a C9.25 anyway.

That's like asking a parent to choose a favorite child. 😲