Louis D

If you're curious about the 20mm eyepiece's internals, a contributor on CN did a tear-down, clean-up, and rebuild recently. It's actually a rather complex little beast.

Soap-Box-Mode-On: Remember, because China is considered a developing economy, the Universal Postal Union affords it much lower shipping rates than those afforded to developed nations allowing it to ship items cheaper across the globe than the developed nations' businesses would have to charge to ship it locally. This forces the developed countries' postal systems to absorb the difference in cost. It is for this reason the US is threatening to pull out of the treaty establishing the UPU unless things change vis-a-vis China. Soap-Box-Mode-Off

You could also try to locate a UK supplier of vinyl caps who will sell small volumes.

I thought that too until I noticed they all have 6 elements in 4 groups compared to the Meade MWAs which have 7, 8, or 9 elements in 5 or 4 groups. However, I found the same eyepieces available from Kokusai-Kohki as Magellans, and they claim they have the same lens organization as the Meade MWAs. Does TS have the specs wrong on their website? Ultra-wide field of view MAGELLAN (magellan) series eyepiece Product number Focal length sleeve coating Eye relief Lens configuration weight Apparent vision Dimensions (mm) Tax-included price ma5 Magellan 5mm 31.7 mm Finished multi-coated Koba coating 13 mm 9 pieces of 5 groups 280 grams 100 ° Total length: 111 diameter: 49 ¥ 27,800- ma10 Magellan 10mm 19.7 mm 9 pieces of 5 groups 380 grams Total length: 100 diameter: 58 ¥ 27,800- ma15 Magellan 15mm 2 inches 20 mm 8 in 5 groups 620 grams Total length: 117 diameter: 68 ¥ 29,800- ma21 Magellan 21mm 7 in 4 groups 700 grams Total length: 116 diameter: 72 ¥ 29,800- Performance of WATERPROOF: JIS waterproof protection grade 7 equivalent ※ (※ JIS waterproof protection grade 7 equivalent, maintain the waterproof state in water 15cm / 30 minutes)

I have the 13mm, 17mm, and 22mm AT AF70 versions. The 22mm is stupendously good. The 17mm starts to show lateral chromatic aberration, but has a flat field mostly free of astigmatism. The 13mm has about double the chromatism of the 17mm, but is still mostly flat and astigmatism free. $70 is a decent price for the 13mm, just be aware that you'll see lots of pretty rainbows starting around 70% center to edge on bright objects. I actually like the 12mm Meade HD-60 better at this focal length. Eye relief is about the same, it lacks edge chromatism, has a bit more field curvature that can be focused out, and has some unobtrusive edge astigmatism. The apparent field of view is narrower, but more usable.

If it's a long barlow, you may not be able to rack the focuser in far enough to reach focus. If it's a short barlow and you're able to reach focus, it may introduce aberrations of its own unless it's a high quality barlow. I tend to prefer individual eyepieces in refractors (I have the AT72ED). Newts are more forgiving of long barlows because it's a long way from the focuser to the secondary, so they can be inserted all the way into the focuser, unlike the situation with a refractor and diagonal. If you used the refractor straight through without the diagonal, then the long barlow would not be an issue. I keep coming back to long barlows because the older, affordable, Japanese made long barlows of the 90s tend to give better views than today's Chinese made short barlows for the same money (around $50 to $70 used vs. new).

Agreed. With the introduction of the 30mm APM UFF, there's no reason to hunt down a 30mm Baader Scopos Extreme. I may still pick up a 35mm Panoptic someday if I come across one with the flush mounted eye lens for a good price.

I compared the 35mm Baader Scopos Extreme to the 35mm OVL Aero ED last night on rich star fields in my 8" f/6 Dob with GSO coma corrector. It was no contest. The Scopos is sharp right out to the field stop while the Aero ED degrades slightly starting at 50% out and gets noticeably astigmatic from 75% out to the edge. The Scopos is also quite a bit sharper. I could detect slight granulation in M22 in the Scopos on axis, but could not in the Aero ED. The sharpest part of the Aero ED is a fraction of the Scopos's sharp field. The eye relief is very generous on the Scopos and very tight on the Aero ED. Win goes to the Scopos last night.

Just came back inside after spending four hours comparing the HD-60s to the Paradigms (BSTs) to other similar focal length eyepieces in my collection using my 8" f/6 Dob with a GSO coma corrector. I observed a bright star, Jupiter, M22, and Saturn. The coma corrector was removed for 10mm and below eyepieces because I was seeing false color unsharpness with it, probably due to residual spherical aberration. Eyeglasses worn with all eyepieces due to strong astigmatism. Here are my recollections: The 25mm Paradigm has field curvature and astigmatism becoming apparent by 50% center to edge. The 25mm HD-60 has no field curvature and much less intrusive astigmatism starting around 75% center to edge. Both seemed equally sharp and contrasty in the center. Eye relief is the same. I had to remove the coma corrector to reach focus with the HD-60, and even then it was still sharper from 50% on out to the edge than the 25mm Paradigm. Win goes to the HD-60. The 24mm APM UFF is sharper center to edge than either, but has a less distinct field stop than either. Tough call between the HD-60 and UFF, especially considering the price difference. All three are worlds better than the 23mm Vite Aspheric which has astigmatism and sharpness issues. The 18mm Paradigm also has field curvature and astigmatism, though not as strongly as the 25mm. The 18mm HD-60 is has no field curvature and similar levels of astigmatism. The win goes to the HD-60 due to much more generous eye relief and flatter field. Both are significantly better than my 19mm Russell Konig which has loads of astigmatism starting at 30% center to edge. My 17mm AstroTech AF70 was flat of field and had very little astigmatism, but it did have slight lateral color in the last 20% of the field. I would probably recommend it over either the HD-60 or Paradigm, especially if it can be found used for a similar price to the HD-60 new. The 15mm Paradigm is only marginally better than the 18mm in field flatness and astigmatism. My 14mm Morpheus, Pentax XL, and Meade 4000 UWA smoothie all resoundingly trounced it. I definitely recommend skipping the 15mm Paradigm. The 12mm Paradigm and HD-60 are quite similar to each other. Field curvature was not very strong this time around at this focal length. Edge astigmatism is also quite minimal and non-intrusive. Center sharpness was excellent in both revealing granulation in M22 as well as my 12mm ES-92 and Nagler T4. However, both premium eyepieces held that granulation to the edge while the Paradigm and HD-60 became fuzzy due to astigmatism. All four outperformed my 13mm AstroTech AF70 which has slight edge astigmatism and no field curvature, but has vast amounts of lateral color at the edge leading to very pretty rainbows instead of pinpoint stars. Win goes to the 12mm HD-60 due to much more comfortable eye relief. The 9mm HD-60 performed very similarly to my 9mm Morpheus and 10mm Delos. The latter two had slightly better contrast, but sharpness was similar. The 8mm Paradigm was slightly fuzzier across the field than the 9mm HD-60. It wasn't much, but it was harder to get a sharp focus on the planets or M22. Eye relief is getting tight with it. The 5-8mm Speers Waler zoom had no issues at 8mm with sharpness. Win goes to the 9mm HD-60. The 6.5mm HD-60 is a gem. It performed just about identically to my 7mm Pentax XW center to edge. The Pentax was slightly sharper and contrastier, but the difference was subtle. The 5mm Paradigm was a struggle use due to the tight eye relief. I removed my eyeglasses and found the view about the same, just easier to take in. I'm not 100% sure, but this eyepiece seems to have whole field brightening. The sky background was noticeably brighter than in my 5.2mm Pentax XL or the SW zoom set to 5mm. Sharpness seemed similar to the 4.5mm and 6.5mm HD-60s once best focus was found, but it is more difficult to find sharp focus, as was the case for the 8mm Paradigm. The 4.5mm HD-60 is slightly less sharp than the 6.5mm HD-60 or 5mm Pentax XL, but not by much. I put my 3.5mm Pentax XW in to check to see if it was seeing conditions, but the Pentax was nice and sharp, so it was the 4.5mm HD-60. Still, it snapped to sharp focus much more authoritatively than the 5mm Paradigm and had slightly better eye relief. Win goes to the 4.5mm HD-60. Overall, I would steer clear of the 15mm, 18mm, and 25mm Paradigms if you can stretch to the 18mm and 25mm HD-60s. The former just have too much field curvature and edge astigmatism to be overlooked by the discerning observer. Either 12mm was quite nice, though the HD-60 has much better eye relief. I would get the 4.5mm to 9mm HD-60s over the 5mm to 8mm Paradigms if budget allows or if you need to wear eyeglasses. However, it is likely you can get by without them at these short focal lengths. If cost is an issue, there isn't anything all that bad about the 5mm and 8mm Paradigms except for focus snap, eye relief, and background darkness. Either line of eyepieces is a major improvement over older 60 degree designs like Konigs. Eye relief at the short focal lengths is much better than with Plossls. Overall, both are lines are a major improvement over the eyepieces typically packaged with starter scopes. My recommendations above are simply to highlight the often subtle differences between the two lines for someone contemplating buying one over the other.

Welcome to SGL from a fellow 'Merican. 🤠 Thankfully, the US doesn't generally charge import duties on items under $800 and most states expect you collect the sales tax yourself and remit it, which pretty much no one does. That, and the GBP to USD exchange rate is excellent right now. I've bought a fair amount from Britain lately because of all these reasons.

A contributor on CN did a tear down and rebuild of the Celestron 20mm erecting eyepiece. It's quite an interesting read.

I'll have to double check, but as I recall, most AO and B&L microscope eyepieces were singly coated with magnesium fluoride (light violet) back in the 60s and 70s. Russian made microscope eyepieces of the 90s were more complexly coated and appeared green with hints of other colors. I don't know about modern, Chinese or Japanese made microscope eyepieces. I'm sure high end microscope eyepieces from Zeiss, Leica, Nikon, and Olympus are fully multicoated.

Never having bought an entry level telescope kit, and for the edification of future readers, could you expand upon what eyepieces come with the 130EQ and what makes them so bad?

There's also the 5mm BST Starguider from FLO, our forum sponsor. I have the Paradigm version, and it seems quite sharp across the field. I'll have to spend more time comparing it to some other eyepieces I have in that power range, but initially, it seems quite good. If you pick up a used one and don't like it, it should be quite easy to sell it along without much of a loss.

I was going to say, it sounds a lot like CN's Martin Pond's "di-plossl".

I used to live withing 2 hours of NYC, and I can confirm the MW is a no-show there. Your best bet from your location would be to head 5 hours NW to the area north of State College, PA, near Keating, PA. That area is around a Bortle 2/3, so you should be able to see the MW from there.

So, do you still have and use the 32mm TV Plossl after all these years? I still have my 5.2mm Pentax XL from 1998 that I use regularly. The 14mm XL has been supplanted by multiple others in that range, as has my 9mm Vixen LV, both from 1997/1998 when I started out.

If you look a few posts down from the one you quoted, I corrected myself after some research with the Wayback Machine : Richard Keppler asks about positioning the new 4x Powermate with a Paracorr. Which goes first? Unlike the 2x Big Barlow which must go ahead of the Paracorr, either way is fine with the 4x Powermate and either way is approximately parfocal for most eyepieces. Nick Black asks if there are any problems using a Big Barlow with a Paracorr. Not if you place the Big Barlow ahead of the Paracorr. In other words, eyepieces should always go directly into the Paracorr when using a Big Barlow. Since the 2" Big Barlow won't slip all the way into the Paracorr, it does not reach its parfocal point and changes the Paracorr correction. As an aside, you can place Tele Vue 1.25" Barlows or Powermate into the Paracorr because these are parfocal devices. Which then raises the question of how to use the Big Barlow with SIPS.

Your next experiment should be to compare the 11mm+2x combos with premium 4.5mm to 6mm eyepieces to see which is better. I've found my 3.5mm Pentax XW and 5.2mm Pentax XL to perform better contrast and sharpness wise than barlowing any of my 10mm to 12mm premium eyepieces. It's close with the best Japanese made barlows from the 90s, but the designed together combinations (negative-positive eyepiece designs) still work better. I don't have any short focal length, positive-only eyepieces like orthos or monos to compare because even at a 1mm exit pupil, I still see some residual issues with my observing eye's massive astigmatism so I wear eyeglasses at the eyepiece even at high powers. By 0.7mm the effect is largely gone, but floaters then become a huge issue for me. I will say that at highest powers, my 2" GSO ED 2x barlow plus TV PBI combination is not as sharp as my 2" or 1.25" Orion Deluxe fully baffled Japanese barlows, 1.25" TV 2x barlow, or 1.25" Meade 140 APO 2x barlow. I don't know if it is a case of less is more or that the slight mismatch between the GSO and PBI becomes apparent at high powers, but it is there. On the other hand, as @John noted above, ordinary barlows noticeably vignette on large field stop eyepieces while the telecentric GSO+PBI combination (Powermate-like) does not and yields beautiful views with widest or near widest field eyepieces. I have yet to try the Celestron Ultima 2x barlow because everyone over here wants over $50 for them, and I can't justify spending more than $35 on a barlow simply for comparison purposes.

Try the technique I've been mastering taking photos of the AFOVs of eyepieces with my cellphone camera. Put your thumb and index finger around the rim of the eyepiece. Next, lower your phone until the field stop just pops into view and the image is centered. Roll your thumb and finger to come into contact with the phone, and then raise and lower your phone using your finger and thumb to maintain a stable connection to the eyepiece and to keep it level and centered with respect to the eyepiece. I couldn't get decent photos just trying to hover it above the eyepiece. There are just too many variables at play (pitch, yaw, x/y/z placement) to get a good image.

I have a couple of 2" GSO (Revelation/TPO/OPT) dielectric diagonals that I use with my AT72ED and 127 Mak to good effect. They're very sturdy and don't seem to degrade the image in any significant manner. I tried a cheaper 2" diagonal, but it had flexure issues as well as a tendency to tip eyepieces in the holder when tightening them down.

I would pick up a used 1990s Meade 140 2x barlow like this one. I've A/B compared it with my Televue 2x barlow, and the two are basically identical. The only low cost barlow I've found that's cleaner is the 1990s Orion Deluxe 2x fully baffled barlow, but it is a monster at 6 inches in length and much more difficult to find. I like the Meade so much that I've picked up a total of three of them. One for regular use, one as a backup in case I drop one on cement, and one for reaching focus with a binoviewer. The fact that the optical nosepiece is threaded in the standard 1.25" eyepiece thread means it can be threaded onto eyepieces or onto the front of binoviewers or star diagonals.

How much for your ultra-rare 32 nagler? 😉

I'd be terrified having a cat lurking about behind an open eyepiece case perched on the edge of a table. 😱 The cats I've known over the years have a tendency to bat at things with their paw at random times.

I have a late 90s Lumicon OIII that has given me my best views of many nebula including the Veil nebula which is all but invisible without it from my backyard.