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JTEC

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  1. This contains some useful general advice from the renowned Roland Christen about eyepieces for binos. His contribution is towards the end of the article. http://www.darksights.com/Binoviewers.htm
  2. Plenty to chose from 🙄. Mostly around mounts: bad carrying practice with equatorial heads like EQ6s but years ago with one of the weighty AE mounts. I never actually drop the mounts in question but, for some time after the AE incident I wished that I had. It mucked my back up for some time. The mount would no doubt have escaped but for a scratch or two. Lowering a mount awkwardly or ‘saving’ it can also put your body through some dangerous extended positions. My old 12.5 inch Meade Starfinder was something of a beast in this regard (though it performed well). It was heavy, fat and slippery, especially when damp. That gave me a few tweaks. And, of course, big Dobsonian bases can catch you out, as you do the straight leg waddle but in a dodgy extended position. So can lowering heavy Dob OTAs into their base, especially if you don’t slot in the bearings first time and have to support and manoeuvre the weight of the tube for longer than you planned for. My ‘worst’ scope accident was when I stupidly failed to properly secure the legs of an early Berlebach tripod carrying a GPDX. It collapsed like a shot giraffe and the mount cut into my forehead as it fell, leaving me with a scar. Nowadays I am much more careful!
  3. Andrew, not wishing to be in any way confrontational, but I do think that’s a highly questionable generalisation. 🙂
  4. Agreed, Louis. It is an extra bit of faff. Like you - and I guess this is my answer to the OP’s question - I don’t use them all the time. I was referring to being able to coordinate the view from two eyes. If something is skewiff in the system it won’t be possible, regardless of the skill of the observer, and in the BV optical and mechanical train there are quite a lot opportunities for wonkiness.
  5. I don’t feel it’s quite that cut and dried. Absolutely, imv as many others’, hugely advantageous for lunar and planetary. But I’ve had some wonderful views of brighter nebulae, especially M42 with binos through both my TEC and more especially, thanks to the aperture, a C11 I used to own. Without question more immersive than mono. Globulars are also a great binoviewing target. Again, to my eye, improving on mono, thanks to that illusion of depth and 3-dimensionality. The 18mm Tak LEs have been mentioned a couple of times - fwiw these are one of my absolute favourite binoviewing eyepiece pairs. Another thing to consider is that you don’t need pairs of expensive eyepieces. I use the Tak orthos; the BCOs and lots of others should also work pretty well I think. There’s probably a little bit of a knack about using binos but in terms of viewing technique I honestly don’t feel it’s much different from using ‘ordinary’ binoculars. What is different is that there’s a lot more system to be collimated and kept orthogonal, starting from the scope, through the bino and all associated prisms etc and ending with the eyepieces and the accuracy and security of their seating. And potentially at high mags where errors too are magnified. I don’t have any real evidence for this but I’m convinced that it’s this kind of thing that’s at work when people find binoviewers ‘difficult to get on with’ but are happy sweeping around with their 10x50s. Anyway, some food for thought 🙂
  6. This must be the first thread I’ve encountered anywhere ( though I’ve not dug into CN lately) where the quality of the TEC140 is being picked at 😂. I’ve owned #165 with the FT focuser from new. It is an absolutely marvellous scope. Es Reid tested mine and confirmed this. I don’t know if the fluorite version is any better visually - I’m at a loss to see how it could be. Comparing fairly similar competitive scopes is never likely to be an objective exercise because user tastes differ, eyepieces perform differently in different scopes, ergonomics, feel, etc etc. Too many variables personal and instrument related. It beggars belief (if you’ve spent time with one) to hear the TEC140 described as ‘lacking’ something 🙄. That said, it is ‘only’ a 5.5 inch scope and, beautiful though its images are, it’s inevitably outperformed in terms of resolution by decent bigger scopes. Given that it’s optical quality is pretty much as good as it can get (see Chris Lord’s analysis/review), I personally take evaluations of smaller telescopes outperforming it visually with a pinch of salt. Other factors than optical have to be involved. And, by the way, where are all those leaky oil-spaced triplets dripping all over the place?! 😂
  7. The Planet is certainly beautiful and very solid but heavy. I bought it for my AZ100 and TEC140. If buying again, I’d probably go for the Uni
  8. Sorry about that - please see repost 👍🏻
  9. Here’s another go with Yuri Petrunin’s eyepiece choices for the MkV binoviewer and the TEC refractors. Hope it works this time!
  10. For interest, here’s Yuri’s choice of eyepieces for bino and TEC140.
  11. Hi Martin, I use a Zeiss bino with my TEC140. (Yuri Petrunin of TEC opts for a par of 10mm Delos with that scope.) I have one 10mm Delos and find it a standout eyepiece but can’t quite bring myself to fork out for a second …. My go to eyepiece pairs are the 18mm Tak LEs, which I much prefer to the pair of 17.5 Morpheus I tried (I kept one), and the 9mm Tak ortho. (Plenty of people, of course, do like the Morpheus in the bino role and supposedly they were designed with that in mind.) I also have Tak ortho pairs in 12.5 and 6mm. They are all excellent. The 18mm LE and the Tak ortho 9mm get the most use in the TEC and in my 12” f6 Newtonian. I always use them with either the x1.7 (gives about 1.5, reportedly) GPC or the x2 2” Powermate ahead of the prism. Hope that’s some use, from one Surrey Hills dweller to another.
  12. Me too. FWIW, I’ve tried most of the contenders over the years and have settled on the Televue Bandmate OIII. If there’s such a thing as a ‘best’ such filter, it would be my suggestion. Just to muddy the ‘UHC’ waters a little, you might like to spare a thought for the Omega/DGM NPB filter, which, along with many other observers, I like a lot.
  13. I think it depends so much on the item that percentages are hard to give. I thought recently about selling my hardly used Vixen HR 3.4 eyepiece - letting it go for 60% of the purchase price, that’s to say £130 seems a bit too generous to me, given that there is also postage and insurance to be deducted from that. On the other hand, I wouldn’t feel justified in asking as much as 60% of the original value for a rickety 15 year old Dobsonian with resident spiders. I’ve heard 75% now 60% … personally, when I sell things, I start by removing the VAT (there is an argument for not doing so, of course), then make what I think is a fair deduction for condition. I never deliberately over price things in the hope of getting more than they’re worth; equally, I do ask what I honestly think they’re worth. I don’t do this to be saintly - it just has the advantage of putting things on a rational, arguable basis. In the end though, the bottom line is always whether anyone actually wants to buy what you’re selling!
  14. Like John, I really miss shared observing events. But any visit to the shops round here shows that ‘common sense’ can’t be trusted as a way of ensuring Covid-responsible behaviour. Personally, I wouldn’t be too worried about being with a few fellow observers I knew out in a field, using my own scope. But we know the virus is transmissible by the eye-route, so sharing scopes, and specifically eyepieces, sounds like a very bad idea indeed. Wiping eyepieces doesn’t sound very practical; whatever the stuff used, I wouldn’t want it near my eyes and I can’t imagine it would do the eyepieces much good either. So, for me, it’s still a non-starter. Helluva shame though … .
  15. As others have said, should work without a problem. I routinely used my Baaders with Baader 1.25 prism on C11 with 2x Powermate ahead of the bino. No focus issues at all. And absolutely worth it. The views of many objects - the Moon, for example, and brighter DSOs were so engaging and immersive that, for these targets, I never bothered with mono viewing again. Every reason to think that you’ll soon sort this out - hope so.
  16. Here’s something else to scramble your brain ... in a good way 🙃 https://www.cloudynights.com/articles/cat/user-reviews/24-26-mm-eyepiece-comparison-r2651 FWIW, I have the Ex Sci 24mm 68* and like it a lot.
  17. Just as John says, the Powermate seems ‘invisible’. Actually, I have the 2” and mostly use it ahead of the binoviewer. I don’t generally ‘Barlow up’ longer eyepieces to achieve shorter focal lengths, except to experiment, usually preferring to use the shorter focal length eyepiece itself. But that said, some eyepieces benefit from being Barlowed (though the Powermate isn’t exactly a Barlow), one example, quoted by Bill Paolini, is the 10mm Burgess Ultra Mono. And while some eyepieces in some systems respond very well to Barlowing and some less well, there need be no fear, imv, that a modern, high quality Barlow or Powermate, by introducing ‘more glass’ into the train, will inevitably degrade the image. There are more bits of glass in some of our top performing eyepieces than under the counter and behind the bar at the Badger and Candlestick.
  18. I can’t join in the levity around this. Most SGL members will have read about the global increase in overall sky brightness due to the cumulative effect of the stuff that is already in orbit. The Starlink, OneWeb and other satellite megaconstellations that have already been launched, or are scheduled and anticipated, will be intrusive in unprecedented numbers, frequency and scale. They will contribute significant polluting light on their way up and down and once in operational orbit. Elon Musk promised zero impact on astronomy but the mitigation measures that have been trialled so far haven’t come close to achieving this. The plan was to keep the brightness below mag 7 in orbit. Mag 7 is not ‘faint’ - it’s bright enough to be naked eye visible from the most precious dark skies we have and certainly bright enough to degrade data for professional and amateur astronomers. For amateur imagers, this means some added nuisance - for professional astronomers working scopes like the Vera C Rubin, things are more serious. There’s no question that the megaconstellations will contribute to degradation of the night sky; the question is whether their supposed benefits make that worthwhile. Personally, I don’t buy the ‘it’s for the good of mankind’ argument and believe they have nothing to do with altruism and everything to do with the exploitation of markets. Others will see it differently. For now though, I would urge lovers of the night sky of all sorts and persuasions, to get over the immediate fascination of seeing these things moving against the stars. What we’re seeing now is just the thin end of a gigantic wedge - those little lights in the sky are harbingers of very bad news for ground based astronomers and for anyone who values the beauty of an unspoiled night sky.
  19. I’ve actually been very impressed with the 6.5 Morpheus in the TEC 140. During the recent Mars opposition, I spent a lot of time cycling through various eyepieces in that sort of range, including the 5 and 7mm Pentax XW, the 6mm Tak ortho and 9mm Tak orthos x1.5 in the binoviewer. The Morpheus gave a distinctive, sharply etched view that separated it from the others. I’m not, of course, saying it was ‘better’ - but it certainly, imv, belonged in that company. All of the eyepieces and combos gave excellent views and each differed a bit in character and feel from the others. Together they built a picture fuller than anything just one of them could supply. I suppose my point is that, within reason, slight inconvenience in use and things like whether the edge is super sharp when you’re looking at the middle are well down the list of criteria to select eyepieces by. There are several things I don’t like about the 13mm Ethos in actual use, for example, but I’ll put up with those. I prefer the comfort, form factor and handling of the XWs to the Delos but I prefer the freedom from colour of the Delos to the XWs - both are terrific eyepieces. When we have so many eyepieces that deliver the ‘core business’ so astoundingly well, we can get very nitty-picky about peripherals. 🙂
  20. To my eye, the differences are slight but real. If the budget allows, there may be a case for having one of each! Not an absurd extravagance when you think what we spend on eyepieces. 🙂
  21. Thank you, Don. That’s tremendously interesting and informative. This feels like (yet) another instance of horses for courses. I wonder if, with the increasing use of blue-rich LED lighting and ubiquitous scattering, that drop of in reflectivity/transmission in the blue might be advantageous in some circumstances and with some targets.
  22. I believe that the ‘prismatic smear’ that Don refers to might be somewhat greater with the 2” prism over the 1.25” because more glass is being traversed? I have both the Baader-Zeiss prisms and like them a lot; much prefer them to the AstroPhysics dielectric I used to own. However, I recently got hold of the Baader 1.25” BBHS and the difference in colour rendition and range is obvious. This is now my preferred diagonal in the 140 f7 apo. I am so taken with these qualities that I began to wonder about replacing the alu coatings on my 12” Dob with modern, suitably protected silver. That’s a different thread I guess. I expect it would be pricey to do but that’s academic at the moment because I can’t find anyone offering to do it 🙂. Any suggestions welcome!
  23. I have Tak ortho pairs in 6,9 and 12.5 and a pair of 18mm Tak LEs. The LEs seem to be a mixed bag. I like the 18s but got rid of the 10s. Like you, I can find no advantage in the LEs over the abbe orthos, and they cost more too. Interesting about the BCO over the Delos - and the BCOs are a fraction of the price at £49 against £336 current FLO prices. Given your experience with them, that has to be some kind of a bargain.
  24. The straightforward answer would be Takahashi eyepieces ... that would also be my suggestion in terms of visual experience for outlay. I’m fortunate to own a TEC 140, which is a refractor in the same quality class as a Tak, and a number of high end eyepieces, including Delos, Pentax XW, Ethos, Morpheus, Tak TOE and Vixen HR. I also own pairs of the a Tak orthos which I use singly or for binoviewing. In their different ways, these are all terrific eyepieces. That said, the sharpest, most transparent views of solar system objects and DSOs are, albeit marginally, with the Tak orthos. They’re also the cheapest. The TOE and HRs are also excellent, but using them takes you to small exit pupils and places where other factors like seeing, etc are more intrusive, and it becomes more difficult to make definitive comparisons. That said, I find the performance of the Tak orthos ‘Barlowed’ with Powermate closely comparable to that of the unbarlowed TOE and HR. For middling focal lengths, of the eyepieces mentioned above, for sharpness and transparency, I’d put the Delos second behind the orthos but only very marginally ahead of the rest. Until recently, I swore by the Baader Zeiss spec prisms and I still think these are exceptionally good - clearly better than, for example, the William Optics and AstroPhysics dielectrics I used to own. I’ve just been testing a Baader BBHS (silvered) mirror diagonal though and I think if I could only keep one diagonal it would be this. So, my straight answer to the OP’s question would be: Tak orthos and 1.25 Baader BBHS mirror diagonal. I’d also suggest planning for a decent binoviewer when the budget allows because, for solar system viewing especially, that will transform your observing pleasure and effectiveness more than the difference between any two eyepieces of even broadly comparable quality.
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