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You mentioned 5-6" reflectors as starter scopes, and pictured a 6"dob, and a price range of 200-250. That only applied to the 5", as 6" dobs are now, and at the time of filming, in the $400 range.
Keep the example images on the screen longer!
Comparing SCT's with their cousins Maksutov-Cassegrains would be interesting too. I have heard the following points: 1) Maks have thicker and more complex corrector, and because of that, due to economic considerations, they're limited to about 6 inches of aperture (bigger corrector lenses for Maks are simply to expensive to manufacture); 2) Since Maksutovs have thicker correctors, they need more time to reach ambient temperature than Schmidt-Cassegrains; 3) On the bright side, Maksutovs have smaller secondary mirrors, which means less obstruction for the light, and bigger effective aperture, compared to SCTs of the same size. I have also noticed that Maksutovs have greater focal lengths and slower F-stops, but i'm not sure this is a hard rule. Are these points correct? Have I missed anything?
Thoughts on the Tele Vue Delos 17.3 72°?
What you refer to as a non flat, fisbowl type view, only noticeable when panning the scope, is common to almost all designs that offer wide fields with sharp stars at the edge. If you remove the fish bowl effect, you get astigmatism at the edge, for astronomy this is not good, so al nagler allowed the fishbowl effect, in order to get sharp stars to the edge. Terrestrial viewers absolutely hate naglers and panoptics for this reason. What you refer to as a flat field in your videos, is not what an astronomer would consider a flat field since the stars are astigmatic in the outer field. But that wont make you seasick like the fishbowl effect can be when panning around a terrestrial vista during the day. The exception to this would be the LVW and it's more famous, but not quite as good clone, the hyperion, which started out as the orion stratus, which was the replacement for the more expensive orion branded LVW. The pentax XW, in 1.25" sizes, was also designed with their high end spotting scopes that have interchangeable eyepieces in mind, and since they are also very similar to the LVW design, tend to be both flat and sharp to the edge. I once had Ken Jones, a professional photographer with a popular photo equipment review website, come in to the store i was working at, because he had come across an old C8 he wanted to use as a high power Terrestrial scope, but when he tried televue nagler and panoptic eyepieces, he was highly bothered by the fishbowl effect. He still wanted a decently wide field of view, and true premium optics, so no hyperions or stratus. He ended up leaving with several vixen LVWs. I got a decent vixen spiff that week. It would be beneficial to the beginners watching, to not refer to eyepieces that can't deliver sharp stars to the edge, even if they don't fishbowl, because fishbowl is not as offensive on a star field, and most would rather have some fishbowl, even pincussion and barrel distortion, in order to have non astigmatic stars to the edge of the field, than to have a field with no field distortion but seagull stars in the outer portion. You have mentioned several eyepieces as having stars sharp to the edge in your dob, that are known to be anything but. But tolerances and expectations vary. I myself started with 2 very slow scopes 20 years ago, an 80mmf11 refractor on a cheap goto mount with a tiny leg aluminum tripod and a plastic tube clamp designed for the ST80 f5 version of that scope, it was very shakey, but I was able to make it work, and had plans for modifying it to work with my next planned purchase which was an even slower 127mm mak on the skyview pro eq5 class mount with dual axis drives, since I planned on getting a separate 8" newtonian OTA later on, and using the 80mm piggyback as a manual guidescope for film astrophotography, and using the 127 on the goto mount with the modification of a baader bracket which was vixen dovetail compatible, and a better tripod equivalent to a nextar 5, that came in the form of a surplus sale on tasco starguide 4 tripods. I went in too much detail out of order . My first accessories purchased when the 80mm was all i had were a 32mm plossl, ultrablock filter, and a then $50 meade kit at sharper image that included an 18mm WA 67deg field (not an 18mm SWA), a 5mm plossl and shorty barlow) the 18mm worked fine in that scope, and also when i got the f12 5" mak. But when I finally got my 8"f4, one of the last from hardin, ouch, the 18mm no longer was even remotely close to being usable. Plossls were ok, and a 13.8mm true meade super wide was much better than that joke 18mm WA, but still had lots of astigmatism in the outer 1/3 of the field. But with the barlow it sharpened right up. I was hooked, and my next significant eyepiece purchases were used 16mm nagler type2 taiwan an, old smoothside version of the original 8.8mm meade ultrawide, and an old smoothside 4.8 nagler and a 7mm nagler taiwan that had a ring of fire at the edge not common in 7mm naglers, it might have been a neaf blem. I later got a Japanese 7mm that didnt have the ring of fire along with a Japanese 12mm type 2. With a fast telescope, I needed these naglers and one well regarded nagler clone, in order to have good stars to the edge, if not quite perfect because I did not have a paracorr for the first 2 or 3 years. A 10" f5 dob also came within the first year or 2.
This type of eyepiece is best used on slow focal ratio scopes, cassegrain and long refractors, not fast dobs. Same goes for the swan.
They were definitely going for the look of the baader
Unless they radically changed the design sincd when it came out, I am shocked to hear anyone describe it as sharp to the edge. Unlike the other hyperions, it does not have a negative group in the barrel, and is really nothing more than a moden updated erfle or widefield design. They would have to go with a highly concave field lens like the panoptic and es68 in order to have good edge correction in fast scopes. It wasnt that way when it came out and.for several years after. I would think if they made such a major change they would advertise it, maybe give it a mark 2 designation. I doubt this has happened, and maybe we have different definitions of sharp to the edge
With a name like on step, I would think it would use stepper motors. If it makes a constant whining sound when slewing, like a cg5, meade LX, or most small goto mounts, it is a servo, if it has a pitch that varies as it ramps up, like an atlas, then they are steppers. Servos require encoders to know where they are, whereas steppers can calculate the number of steps
5mm is pushing it on f9 slower scopes. I never had a problem with pentax eye placement because the twist up eye guard can easily be set to the perfect distance, and then you don't have to worry about it. Not all of the focal lengths are perfect though, the 20 and 40 do have some field curvature, and althogh the 20xw was more comfortable to look through, a 20mm type5 nagler I compared it to beat it in every area except eye relief, i was surprised to see the nagler put up more contast and brightness, where the smaller focal length pentax usually excells. I was similarly surprised that the 40XW needed slight focus adjustments for the center and edge of the field in a c11. Compared to a meade series 5000 SWA (es68 equivalent), the pentax had more snap in the center, but the entire field of the big meade SWA was sharp to the edge with no focusing adjustments required. When compared to the older japanese meade series 4000 SWA, the center sharpness was better than the 5000 by a tad, and almost as good as the pentax, closer to the pentax than the 5000. But there was astigmatism at the extreme edge that could not be focused out in the older design which was a copy of the televue widefield, where the 5k version is a copy of the panoptic. This made the series 4000 SWA, like the televue widefield, not great performers in fast scopes. For use on SCTs, while the massive 5k SWA has better edge performance, i preferred to use the 4k for the center snap, and the outer astigmatism was still acceptable at f10, along with being not nearly as massive and heavy as the pentax, which is still lighter and less massive than the meade5k. The ES68 version is slightly less massive due to the deletion of the twist up outer housing, but it is still pretty heavy, heavier than the 41 pan IIRC. I ended up selling the 40XW because it was worth the most of the 3, and needing to refocus for the edges or the center was what made the decision to part with it easier. I also had the 10.5XL, both 8.5 and 12 XF (compact 60deg versions intended for spotting scopes). XW use was common in the circles I ran in, so i got to look through many of the other focal lengths, most commonly the 5 7 and 10. The common war was type6 nagler vs xw, and they both came in 3.5, 5, and7, and were close with 10/11 and 13/14. I always found the optical performance in those sizes to be pretty comparable, and all use japanese glass with excellent coatings, so it was usually the choice between 70deg and long eye relief, or 82deg and moderate eye relief, definitely better than the 4.8, 7, and 9mm type 1, but no where near as long as the 20mm eye relief designs. IIRC type 6 had about 13mm of eye relief and it was fairly consistent among the whole line. The only t6s I owned were 3.5 and 7, and i regretfully couldnt resist the urge to sell the 3.5 because it was too strong to use in most of my scopes, and i could still get by with my 3.2mm and 4mm TMB planetary eyepieces. I of course kept the 7mm along with the 10.5xl and the XFs and 5.5uwa till the end when they got stolen. Now I have an old 7mm type 1 again (I had 7mm type 1 before i got the type 6 in the past, always have to have some form of nagler 7), 4.7mm 5kUWA, and 4k UWAs in 6.7, 8.8 and the massive 14mm. The current big boys are the 28mm megaview and 20mm WO XWA, with 17 and 22 LVWs and a 24mm ES68 filling in the gaps with 1.25" capability. The only gaping whole in my set is a maxfield 40 like my previous 2 40SWAs and the 40XW filled, for use in my F10 SCTs and refractor. Would like another 4kSWA, or UO MK70, 42mm LVW or 40mm TV widefield, all japanese. But a WO 40 SWAN would probably do in a pinch. (Not mentioned were my 30mm widescan II and 56mm smoothside super plossl, which were 30mm 84deg widescan III and 50mm 56deg axiom in my pre robbery set)
Pentax has always been a benchmark for eyepieces, until you try a nikon eyepiece
They look a lot like the nagler zooms. Definitely a reverse engineering job, and would bet the inner 50 degs to perform almost as wellnas televue, but the outer 5deg is probably not as good. Was that the case? A common theory is that al nagler was trying to design a long eye relief nagler after the type 1 and 2 had short eye relief except for the 13mm and 20mm. The design was not up to his standards outside of the inner 60degrees, so he scaled it down and created the radian, instead of a nagler type 3. He succeeded with the long eye relief nagler type 4, which i had in 22mm for a while. In my f5 dob, without the paracorr, the stars at the edge were bloated, where other nagler designs were much better in that regard. It sharpened up with the paracorr, and televue ads mentioned that the nagler type 4 was sharp to the edge when used with the paracorr. I tried out a celestron 23mm axiom LX which was better at the edge and didnt require the paracorr. This also applies to 24mm meade UWA and ES82 versions of the same eyepiece. I sold the 22mm type4. The svbony clone looks like a good budget option
Hyperion 24 sharp to the edge? Maybe at f10. The es68 24mm is much better in that regard. I replaced my 24 Hyperion with the earlier meade version 5k swa, and it was almost as good as the panoptic, and now i have the es68 version to replace it after my 24swa was stolen along wjth a bunch of other even more premium grade 1.25" that were in the same pelican style case with my televue pronto.
More people need to try vixen LVW lanthanum superwide eyepieces, which are the original japanese made ones that the orion stratus and later the hyperion which the same as the stratus but with the modular threaded stuff and "phantom.coatings". They were originally available in the US as the Orion Lanthanum superwide, until the stratus came out as the lower priced replacement. They absolutely blow the hyperions out of the water, the japanese make the best glass, along with the germans, but hyperions are NOT made in Germany. The build quality is also amazing and they are slightly smaller. They spec out at 65 degrees, all have 20mm eye relief with rare earth lanthanum glass. They hold up very well compared to a pentax xw or xl, beating some of the pentax focal lengths especially the 20XW not being as sharp at the edge as the 17mm and 22mm LVW. And since they aren't forum hyped like baader, they might be comparably priced or less if not only slightly more than a morpheus, since i remember these being in the $239-$279 range back when hyperions were $130,.radians $250 and type 6 naglers $309. Unfortunately the us vixen dealer closed shop or at least stopped being the vixen distributor a few years ago. Used They arent terribly expensive because not many people know how awesome they are. From 3.5mn to 22mm, and there was a 42mm 2", but that was a different design without the same level of edge correction, much like the old 2" 30mm and 35mm stratos which i believe iirc baader sold as the scopos. The 24mm hyperion and stratus were also a different design having neither corrective negative field group, or a panoptic/es68/5k SWA style highly concave field lens. In the AT66ed f6 apo.that I had at the time and wanted a well corrected max field eyepiece, i tried the 24 hyperion, which was very astigmatic in the outer portion, then the 26mm meade 5k 60deg 5 element plossl, which was slightly better. But not as wide apparently, and still very noticeably astigmatic near the extreme edge. I then got a meade 24mm 5k SWA , which was the original eyepiece to have what would later be the ES68, and it was so much better. Astigmatism was so faint that it wasnt offensive at all, and very good sharpness and light transmission as well. The only thing to beat it in that focal length and field of view is the real deal televue panoptic which is essentially perfect to the edge. The 22mm LVW is also essentially almost perfect to the edge, a little narrower at 65 instead of 68, but much longet eye relief at 20mm. These need more love. I have an orion branded 17, and vixen branded 22. The 13mm and 8mm are probably the best in the line, similar to hyperions, but all the lvws are good, there is not as mucb variation between the focal lengths as there is with hyperion
It would be interesting to see a morpheus vs Delos comparison.
Chromatic abberation at the edges even appears with many naglers. You just confirmed that the 14mm es82 still has the edge sharpness issues that have been there since they first came out as the meade series 5000 UWA. The 14mm is hands down the worst of the line. Don't judge the whole line by the 14mm. Try the 24mm and the 8.8mm. Chromatic abberation will definitely appear in the larger ones which are based on type 5 naglers which also have what we call the "ring of fire" effect. But stars are sharp to the edge, at least as far as astigmatism is considered. With a paracorr the stars at the edges get tighter and smaller, more pin pointy, but that is the fault of the scopes coma when used without a good coma corrector. In a fast refractor, especially a flat field quadruplet, they are amazing. The 24 is very nagler like, the 30mm does not hold up quite as well as the 31 nagler, but it does a decent job. Buying them used, or better yet, the older meade UWA and celestron axiom LX version, is a much cheaper way to get the exact same optics. They used to be $100 eyepieces (1.25 sizes), but when JOC decided to stop supplying other companies with eyepieces and made ES the exclusive source, at least for the US market, they doubled the price overnight to market themselves as a premium brand It worked since so many newbies keep coming in who don't know the old pricing and other options to get the same optics. And because the other options were not available new anymore, making the es68 the only source for a close approximation of the panoptic design, previously available as meade 5k SWA. A few years ago I saw there was a European brand selling the JOC 68s, and had cosmetics and mechanics similar to the twist up meades, but I forgot the name. As for the 82s, most of the other suppliers that meade and celestron had to go to, did not quite match the JOC performance, especially the celestron luminos which replaced the axiom LX. In the case of meade, they had a 5.5mm series 5000 UWA from a different vendor that literally performed like a type 6 nagler, for $129.and frequently on sale.for $99. The 8.8 is pretty good too but I have not tried it in dark skies or on a scope faster than an f6 refractor, that a friend of mine who bought it on my recommendation had. At the time I still had all my old stuff including an f5.4 televue 101 and a 7mm type 6 nagler to pair it with, and it was like.just changing magnification, the edge correction, and overall image quality and contrast and sharpness and even comfort (for a moderate eye relief eyepiece, longer than type 1 and 2, and even the 16 and 20mm type naglers which are pretty tight on eye relief), were the same. I was blown away. But I think it too has been discontinued, and they now have the PWA line, which is the same optically as the WO uwan and orion megaview. The big boy, the 28mm, has nagler like performance, much better than the 30mm ES/JOC. They only come in 4, 7, 16 and 28mm. Unfortunately I never got around to testing the 3 smaller ones, but ever since a friend got one in 2006, and I tried it on my f4 newtonian, I was blown away then, and when it came time to replace my 31 nagler, a used orion 28mm megaview popped up and I jumped on it. The only thing I miss about the 31 nagler, other than pride of ownership and maybe that 2% better performance, is that it is a 31mm, and hence closer to the maximum possible field stop of a 2" eyepiece, than a 28mm with the same apparent field. Technically someone could make.a wider eyepiece, and there have been others, but not with the correction of the nagler, unless that other premium that I believe was Leitz 30mm 88deg, also had good performance in fast scopes, but I never saw one in the wild. I do like widescan type III (or II which I have now because finding the III is hard, and I got mine included when I bought my used TV101), and I also had the 20mm which was 84deg in a 1.25, and the small and tight 13mm as well. The 30mm type III was advertised at 84 degrees, but they are best in slow focal length scopes like SCT, but they are a tad brighter than the naglers, having excellent coatings and less glass, and that japanese "snap" in the center, that even the Taiwan made 31 nagler is sooooo close to. Depending on how old it is, televue coatings change and improve over the years and they don't Indicate or advertise it, so all types.can vary unit to unit in that regard and it is luck of the draw. Mine might have been older since I got it used. Since the nagler was so massive, I did prefer to use the widescan in my f10.scopes, even if the extreme edge was still not perfect like the nagler, it was pretty nice, and my WSII is almost like the WSIII so I am happy to at least have that. Now to get a nice japanese 40mm super wide with the max or close to the max field stop, to replace my meade 4000 40mm SWA. A big hole in my f10 scope lineup. I have a cheap 40mm astrola which throws up nice wide low 60s field, but does not quite reach the edge of the 2" range. I had a 50mm Axiom (original japanese, not the LX , which didn't have a 50), which was about 56deg, and pushed the edge of the 2" field, and happily replaced it with a 56mm mease smoothside 5 element super plossl, which is the brightest, (other than funky 60mm and longer kellners and some obscure stuff from russel, rini, and siebert) eyepiece you can put on a commercially available scope limited to 2" eyepieces. I know I strayed off topic. But eyepieces are the area of the hobby which I am most obsessed with. And in 5 years at a major dealer, I sold many many of them. If you like the baader hyperion and morpheus (I hear great things about the morph but have never looked through one), you should check out vixen LVW lanthanum super wide eyepieces. They are the design that the orion stratus and baader hyperions are chinese copies of (yes the hyperion is made in china, not germany). Orion was the main US source of them until about 2005, and they were branded as orion super wide, lanthanum 65deg 20mm eye relief. And they absolutely blow the hyperion out of the water and hold their own next to pentax XL and XW eyepieces. They used to cost a tad less than the pentax, but they were still in the mid to high $200s range, though I don't know what they cost now and where you can get them since the last US vixen dealer closed up several years ago. I have the 17mm orion branded and 22mm vixen branded, and they are awesome. They all have 20mm eye relief, and a similar look to the orion and baader clones, but slightly smaller, and a higher quality fit and finish. Worth a look if you want to go more niche and less forum hyped, like the baader hyperions are. I am not sure if the morph lives up to the hype, but it sounds like a big improvement over the hyperion. I sold plenty of hyperions as well in my day, when they were about $130-140, and the similarly if not slightly lower priced orion stratus started to decline, even though they wre the same optically, other than the phantom coatings but most couldn't see a difference. Eyepieces.are like a drug
You need to start down the 100 degree rabbit hole. I suggest the APM 20mm. I own the william optics xwa version with the same optics. Avoid the 20mm ES100 if you have anything faster than say f7, but the 14mm is excellent. I think it is silly for the 9mm and lower being 2" only, and borderline silly on the 14mm, but since televues 13mm was the largest 1.25 they made, it is more acceptable. Either way that led me to not persue the shorter focal length ones. In fact I wasnt even planning on buying any of them at the time, but scott got me started by plopping one down on my counter one day at work (astronomy sales at a big dealer), this was from the first batch when the 14 was the only one. I later bought a used 20mm for like $220 a few years later. I got robbed of everything in 2018, but now have the 20xwa i got for around $180 because that version isnt as popular because of the huge wide flat top it has, similar to the 28 uwan which i also have a version of, which is THE best big 2" 82 degree non nagler i have ever seen. Which is also now available as the meade PWA, in the same 4 focal lengths of 4, 7, 16 and 28, as the wo uwan/orion megaview. Give that one a go if you want to closely approach 31 nagler performance. If you have a slow scope, then the es82 30mm or a used 31mm axiom LX, or 30mm meade 5k UWA, as all 3 have the same optics, is close enough for government work. Or a 31mm luminos which i believe is the cheapest option, though known to have some edge of field brigtening. If there was one thing I have been obessive about it has been eyepieces. Let me know the fastest scope you have used the 14mm es82 in, and if it had sharp stars at the edges. My experience with the original meade versin was dissapointing at f5 and i brought it back the next day. And I know for a fact that the early es82s, and at leasy a few years into production had the same issues. I wonder if they finally fixed it or if it is still the same. I think it is the only one that is significantly that bad at the edges. The 4.7 i know is good, and the 24 is outstanding, the 8.8 is another good one, and I already talked about the 30, but it doesn't equal the 28 uwan or 31 nagler at the edges. I will also mention the 5.5mm meade 5k UWA, the ones after they had to switch manufacturers, is a downright equal in performace to a tyoe 6 nagler. I had the 7mm type 6 and when I was in dark skies with my Telvue 101 f5.4, it was like just changing powers, the quality and comfort of the view was amazing, and it was a $129 eyepiece that frequently went on sale for $99. I miss that one, let alone everything else I used to own If you didn't know, the es68 was originally the meade 5k SWA, and it is the only panoptic clone I know of, all other well corrected super, ultra, and hyper wide eyepieces use negative lens group at the bottom. The panoptic uses a highly inward curved field lens, and the es68 which has the same optics as the meades did, is the same type of design. I did a head to head 24 meade vs 24 pan in a small f6 refractor limited to 1.25', the main reason I bought the 24swa. The pan was sharp to the extreme edge where the meade 24, which absolutely destroying the 24mm hyperion I owned before it, did not quite match the panoptic, it was still the best 24mm superwide other than the 24mm panoptic. After being robbed, i did buy a used 24mm es68, because i got an old xt6 with 1.25" focuser, and at the time i also had a meade 114f4 synta made mini dob that i planned to use for wide field on a nexstar gt mount or on its own dob base on a stool, but a run of bad luck had me lose a few scopes and mounts including the GT and a 127 mak, among others, and i lent the 114 dob to someone who later cut me off and said no when I asked for it back. I only paid like 40 for it so I let it go. The 24 would have been perfect for that scope, as was the 18mm meade UWA which was 1.25" unlike the later 2" ES version, but it has coating damage that made jt useless. I also got a 24mm that was even worse. Someday I may find someone who can remove the coatings and make them useable again, though they would be a little dimmer and probably would lose some contrast. But my perfectionism, and owning the xt6 does give the 24 a rightful place, and sometimes when i use my vintage c8 i just leave the original vixen made japanese 1.25" prism star diagonal and 26mm silver top plossl in there, and the view is so crisp, but I do like a wider field at that focal length, so it would be perfect for that. But realistically I usually put a 2" on there and take advantage of my 30m widescan II 84deg, 56mm super plossl and 40mm astrola widefield (until I re aquire a nice 40-42mm classic design, non huge 68-72 deg eyepiece like the meade 4k 40SWA I had, which was meade's answer to the televue widefield before the panoptics came out) I would take a WO 40mm swan in a pinch because it uses the whole 2" field, I am a stickler for that, or as close as possible. But i prefer the old Japanese made ones when I can. Like UO MK70 or televue wide field or others I used to want but cant think of now. The 40mm panoptic and its clones are too damn big and heavy, but if the price was right on an old meade or ES..... But you have a 24pan so you are good. I had the full line of 5k SWA before i was robbed, except for the 15 and 20 because the eye relief was too short, and this applies to the ES68 as well of course. Televue even discontinued the 15mm panoptic because of that. I have to say I really liked the 28 as a nice 100x eyepiece in my c11, and the 34 and 40 were excellent as well. I never really used those 3 in a fast scope because the 34 and 40 exit pupils were getting too big, and I had a 31mm nagler which covered for all 3 of them really, having almost the field of the 40 and almost the power of the 28. I owned a 35 panoptic, but sold it shortly after getting the 31 nag. The c11 and later the SWA set came later, when meade was clearing them out. So i never tried the 35pan in the c11. The set of well corrected 65-100 degree eyepieces i use now are... 28mm orion Megaview 24mm es68 22mm vixen LVW (lanthanum 65deg 20mm er) 20mm WO XWA 17mm Orion Superwide Lanthanum (rebranded vixen LVW) 14mm meade 4K UWA (love the old huge Japanese type 1 nagler killers, 84 degrees) 8.8mm meade 4k UWA 7mm nagler type 1 smoothside 6.7mm meade 4k UWA 4.7mm meade 5k UWA
If I could afford the Leica ASPH 9-18 with APM adaptor then basically reduce the EP collection by a few
Scts don't deliver less than their aperture of resolution, central obstruction may lessen contrast, but it has nothing to do with resolution. If that was the case all those giant observatory scopes would be wasting their time. And if you were using the 45deg diagonal that came with your scope, then you haven't tested it or compared it yet. That diagonal robs light, contrast, adds diffraction and vignettes anything wider than the 25mm plossl.
Please stop spreading the myth that you can't use 2" eyepieces on telescopes with baffles less than 2". Light is a cone not a pipe, if the baffle is not obstructed, there is no problem with 2" eyepieces. You need to go down to a 90mm mak before you start to get vignetting. Not only did I experience this for myself, but I sold tons of 2" diagonals and 40mm swans (72deg, max 2 inch field) to owners of 5 and 6 inch maks as well as c5s and c6s. And many of them called in thinking it wouldnt work because of what they read on internet forums. They didnt get returned, because that is a MYTH, not reality. You only have issues when using larger SCTs that have a 3.25 rear cell to 2" step down plate, which obstructs the baffle. Hence a peterson eye opener for meade lx200s equipped with an obstructing microfocuser, or other solutions like an AP visual back for c11/14, or a celestron or meade specific 3.25" rear cell adapter plate for your Jmi, or starlight or whatever brand focuser.
It is actually a testament to televue, that it can be as bright and sharp as an ortho, while giving a wider field as well as much longer eye relief. It is much easier to make a good ortho, hence they cost less. I used to have a mixed/matched set of the flat top type orthos, from 5mm to 18mm, all the same manufacturer but a few were different brands. The first one I got was an Antares branded 7mm, then I gradually completed the set, mostly UO HD branded ones. I did end up selling them before doing a little research about the current going rates, and I sold them for almost half of what they were going for, and they sold on cloudy nights in less than a minute with a ton of inquiries pouring in after. DOH! Realistically, I rarely used them due to the FOV and eye relief, though they were extremely sharp. They were 40-45deg afov, badder is pushing it going to 52deg in that design, that is if they are true abbe orthos, but then again, orthoscopic is a characteristic , not an eyepiece design. The design is technically an Abbe, or abbe ortho, as other eyepiece designs have been categorized as orthoscopic as well, that have nothing to do with the abbe design. Iirc they were 5, 6,7,9,12.5 and 18mm and I sold the set for $300 and probably could have gotten $5-600 as they were not available new anymore. Another similar (and I think made in the same factory) eyepiece design is the 5 element celestron ultima, which was an answer to the original 5 element meade series 4000 super plossl. These were also sold as Orion ultrascopic, parks Gold series GS-5, and Antares elite plossls. I also had one branded Omcon plossl that appeared and performed identical to the others, so I assume it was the same. And there may have been other brands, I forgot if UO also sold that design or not. Personally, I think they perform as well as orthos, but are wider at 52deg, like the newer baaders which are definitely not made in the same japanese factory that made the orthos and ultimas. It would be splitting hairs to compare them as the 5th element (leeloo) added negligible light loss. A true test would be to compare them to the older Japanese ones. And maybe to televue plossls, and ultima types. Televue plossls are nice, but I found on axis performance better in the ultimas and true super plossls. Televue plossls are modified to fix the edge performance, and the trade off was a slight loss in on axis performance.
Il est magnifiques mais je peux pas me,le,payé 😢😂😂
I also would like to see it working
Thank you Bogdan, your reviews are very thoughtful. You are providing a great service to the AA community.
It can be adjusted to increase elevation. But I didn't like it because I only fitted a specific model of telescope base.
3:07 Thank you--great to see! I own the 22 mm Panoptic (purchased in 1995 and since discontinued). Interestingly, this modern 24 mm Panoptic has less diameter and lots less weight, 233 gm versus a hefty 437 gm for the vintage, dual-barrel 22 mm. The 24 mm Panoptic has similar look, size, mass, ER and AFOV to a discontinued TeleVue from the 1980s--the 24 mm Wide Field.
Thanks Bogdan, your reviews are always knowledgeable, well done and thorough.
Hi Bogdan, I have been watching your videos but it is until now that i write a comment. The Skymaster is a very underrated binocular. I was lucky to get one used that survived the travel from Berlin to Magdeburg with spot collimation. It was a revelation to me due to its versatility, lightweight and quality. Later on, i discovered that it was working around 60 mm instead of tne advertised 70 mm. In any case I loved it and enjoyed during many nights. Ultimately i sold it and got a better 15x70, but i missed the center focus. Overall, it is a nice binocular if you get one properly collimated. Thanks for your videos! Greetings from Denmark!
I own it. I love it. The only thing I had to do was get some riser blocks so I get my auto focuser to clear the dovetail plate.
I wonder if the C5, perhaps even the non-Edge C8, are not what they once were, when US made under Johnson at Celestron-Pacific in the 1970s? Celestron used to market large apertures to professionals, before branching into the amateur market. However, in the early 1970s, every C5 and C8 manual stated proudly that each Celestron telescope was set-up at their factory to deliver diffraction limited performance, the secondary aspherised,, and the system bought to an optical null. Regardless, the C5 remains attractive as one of the most easily portable scopes.
There is definitely more unit to unit variance in the Chinese versions but the newer coatings can make them brighter than older ones, other than the final years of USA production that had starbright xlt. But even the USA models made for a brief time after the halleys comet craze that had demand so high that both meade and celestron wore out their tooling, put some sub par optics on the market, so it is a good idea to try before you buy a late 80s meade or celeston, c5, c8 and 8" meades being the most popular were where most of the issues show up.
Apo frr, please explain the safix of askar models 🎉❤
Hi bro,I tested to fix my cellphone as a finder scope for my telescope but having difficult to use the stellarium plus.any suggestion how to align on the stellarium app?
@yapgideon Hi, its probably a calibration issue with your phone. There is an option inside stellarium to re calibrate the sensors. Try that first. You could also try out a different app to see if the issue persists.
Picked it up a couple of days ago. My initial concern and probably the only concern was that it was bit slow at f6.9. But as someone who lives in Arizona with 320+ days of clear weather, I don’t mind the slow scope at this price. Ironically haven’t got a chance to test it yet, because it’s been cloudy since the day I got the scope 😂
To be honest considering the aperture, these pictures are pretty amazing, good scope for photography in my opinion.
I’ve truly enjoyed every video of yours I’ve watched so far. Definitely getting through them all. Anyway I purchased our first telescope recently and went with a Celestron - StarSense Explorer 8-inch Dobsonian Smartphone App-Enabled Telescope. I spontaneously purchased a Tele Vue 24 mm Panoptic and a Tele Vue 9 mm Nagler. I was thinking of getting either their 2x Barlow or a third eyepiece to be content for a couple years? If I did go with a third Tele Vue eyepiece which would you recommend to complement the two I have and my telescope? Thanks again.
@TransformersHoarder Thank you! I'm glad, you are enjoying my videos. A quality 2x Barlow would be a good choice. The only thing to consider here is the compatibility with mirror/prism diagonals since the 2x Barlow from TV is so long. If you think you are going to get a second telescope in the future that uses a diagonal, then you might consider a 4mm DeLite instead of the Barlow.
Price
It appears to be an extraordinary well built telescope. However, that is a really small aperture limiting light collection.
The 51 Redcat is even smaller and it does a good job of collecting light/imaging.
Any telescopes primary purpose is to gather as much light as possible. All things equal, go bigger. (Ed Ting) To each their own. Thanks! -mike
Mr Damian, newbie here! Are there any way to control an onestep mount with a MacBook m1?
@Pablo.Albino Yes, it should be possible. Although you will need to use Alpaca instead of ASCOM since the latter is limited to Windows.
Askar makes some decent scopes for the price point
Thank you.
Interesting.
Thanks Bogdan, I've a Skymax 150 and im looking for something that's better for deep sky objects, in your opinion do you think this would be better for this?
@graemedevine9651 Yes, because the FOV of the 71F is much wider than the one of the SkyMax and will allow for wider DSOs to fit in one frame.
@@BogdanDamian thanks, I've found an Explore Scientific 102mm F/7 ed apo for the same amount but from your review I think I would be better getting this Askar.
@@graemedevine9651 Прошу Вас, прежде, чем делать такие заключения почитать теорию астрофотографии и технические характеристики телескопов, а именно конструкцию, что такое ED, APO, Super APO, Triplet, Quadruplet, в чем между ними различие и как это различие влияет на качество картинки Если не вдаваться подробности, то условно существуют телескопы для визуальных наблюдений и для астрофотографии. В астрофотографии крайне важна максимальная коррекция оптических аберраций различного порядка, от простого хроматизма, до сферических разного порядка. При визуальных наблюдениях, в первую очередь важна апертура, а при астрофотографии светосила. Да, это прямо связано между собой, но это связано большой разницей в стоимости телескопов. Телескоп из видео чисто для астрофотографии, визуально в него только если на Луну смотреть. Ваш Skymax 150, это телескоп чисто для визуальных наблюдений. Explore Scientific 102mm F/7 ed APO отлично подойдет для визуальных наблюдений, для фотографии объектов дальнего космоса, вам надо дополнить его редуктором фокуса и корректором поля.
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Nice video. What is the practical useful maximum magnification of the Sv503 102ED ? Does the image quality of the Sv503 go down over 200x ? 240x or more ? Thank you :)
@BurningFlame1999 I pushed the 102ED to 236x without losing too much detail. 200x aren't a problem at all.
Hi all, have anybody experience with Artesky Telecentric Barlow lens 2x 2" - APO - 4 Element Design?
I am favoring omegons 10 or 12 dob over other brands. Would you recommend it?
@running2standstill685 Yes, I can definitely recommend the Omegon Dobs. Go for the Pro version, as it comes with a few accessories, that are very useful. In terms of size, I would get the 10" as the 12" is right at the limit of what I can carry outside.
@@BogdanDamian i was gonna go for the 10, as similar to what you said the 12 is already challenging the term portability. But the 12 gathers 40% more light than the 10 according to specs and im too much of a DSO nut to lay off of it 🤣 Additionally Omegon offers a 2 inch UW 32 mm eyepiece and a 10/1 fine focuser which really made omegon so irresistible.
@running2standstill685 I can totally understand. After all I have the 12" for a reason 😅 Omegon is a good choice, let me know has you like the telescope once it arrives.
I got this mount and i love it, only issue i have is that on the azimuth when you change direction it does not turn right away, will take a quarter twist of the knob before it responds, other than that its great.