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newman

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Everything posted by newman

  1. I've been eyeing this one for myself. Seems about the right size to put a few larger ep's and other equipment in it (a few filters, the red flashlight, not sure if I could fit in a Telrad... probably not but that's not that big a deal). https://www.teleskop-express.de/shop/product_info.php/info/p4682_Starway-photo-accessory-case---versatile-internal-distribution.html From what I can see, it offers a nice amount of protection to whatever is inside, has a carry belt, and of course the pre-cut foam on the inside is useful. Haven't had a chance to try it, though.. but I'll probably order it one of these days.
  2. Having a good view of the south is something I'd definitely favor. From your description, I'd say you have yourself a pretty decent observing site, provided there's not too much lp..
  3. There's no absolutes here. Some people don't like ultra wides, others are addicted to them. There's no right or wrong when it comes to eyepiece preferences; whatever works for you is what you should get no matter what others say. Having said that, just trying someone else's Ethos has been a rather expensive exercise for quite a lot of people I know; I have yet to meet someone who's looked through one and didn't immediately want to buy one The thing about the 100 degree AFOV is precisely that you can't see the hard edge of the field (unless you move your entire head to see it); the sort of a soft edge around a very wide field resembles looking through your eyes, thus creating a feeling of "being there". Some people like it, others don't, I still use my ortho sometimes but honestly I can't shake the feeling of looking through a toilet roll when using it - after the ethos's 100 degrees the ortho's narrow AFOV really feels constricted.
  4. I own both a 17mm and a 10mm Ethos, and if I could only keep one I have to say I'd struggle with the decision and probably keep the 17mm, giving up the 10 with a heavy heart. The 17mm is superb both as a finder and a low power DSO viewer making it quite versatile in my scope. The 10mm shows less sky, but what it does show is gorgeous, typically with a darker background than my 17mm making the faint nebulae stick out better.
  5. I use Carl Zeiss's optical cleaning fluid and cleaning sheets of rice paper (should be able to find them in any photo accessory store, they're meant for lens cleaning; also, only use the pure rice paper, not the mositured kind, that'll leave a residue on the lens). The idea behind the rice paper is precisely that it is disposable; each one is used for a single wipe, then discarded. It avoids introducing any filth or residue that may have been present on the cleaning cloth. There's like 150 of those papers in a pack I bought so they should be good for a long time; cleaning any optical surface often is the best way of damaging it.
  6. I own a 10mm Ethos and use it quite a lot. It's a brilliant eyepiece with the price being the only downside that I have seen so far. That being said, I never had a chance to compare it against a 10mm Pentax XW.
  7. Besides the limitations of optical technologies, there's another important factor here; the limitations of the human eye. Even with 100 degrees, you'll have trouble taking in the whole field - most people just can't do it. The cool thing about ultra wides is just that - you don't see a sharp edge, just like when looking with your eyes only, which creates that "spacewalk" or "being there" feeling. But I'm not sure I see much point in going beyond this - there'd just be more space you don't see without moving your eye quite a lot. At which point you might as well just move the scope. If you're just interested into how far the optical technology today could go, that's an interesting question to be sure, and I do believe much higher AFOVs are possible. However, you always "pay" for this as everything is a compromise. An Ethos already has eye relief that's too short for some people, and there's other stuff that comes creeping up with ultra wide fiels, such as pincushion distortion, etc. So I think the real question isn't "how far can we go with AFOV", but rather "how far can we go while the eyepiece still remains usable".
  8. I bought mine almost a year ago and have since used it quite a lot. I actually stopped bothering with mounting the normal finder since I don't really need it in most situations anymore. If we take the bang for buck ratio, this is one of the best (and certainly the cheapest) pieces of kit I ever bought.
  9. Anything with a short focal lenght and plenty of aperture, really.
  10. I'm still in the process of building my ep collection, though I'm taking the minimalist approach. I've found that I don't really like juggling with too many eyepieces in the dark. A 17 and 10mm Ethos have spent most time in my diagonal so far, and I was thinking of getting a 6mm Delos to round off the collection. I really don't think I need anything else - plus a full set of Ethoi would be way too expensive
  11. I would recommend a Telrad. Easy to align, easier to use. When I combine it with an iphone planetarium app that has the option to use the Telrad circles in it, there's no target I can't find that is visible in my scope. It's such a simple thing, but works brilliantly. I was going to get a RACI finder as well, but after putting the Telrad in I found no need tbh.
  12. I was sort of going with an assumption that if he can store a 10", he can probably make room for a 12" flextube - if that is not the case and the 10" is the absolute maximum in size, then it's really a no brainer. But in the OP's shoes I'd do a lot of measuring before making that determination
  13. I wouldn't get a 10" if I already had an 8" - it's not that huge of a difference. Sure, the 250mm will outperform the 200mm one, but it would make more sense to me to save a bit and get the 12" or even bigger - especially since portability isn't an issue in your case.
  14. If you were interested in visual observations of primarily DSOs, then the additional 50mm aperture of the 6" Evostar would give that scope an advantage; CA is a non-issue on the faint fuzzies. It is an issue on planets, which could be mitigated a bit by using a minus violet filter (not solved, mind you) - but if DSOs are the primary target the 6" achro would do a fine job. Of course, another factor to consider would be the size, portability, and weight of this instrument. The Evostar 120 is just small enough to not cause problems when transporting it in my car. The 150 would be far less practical, and would require a heftier and more expensive mount. Also, prepare for a lie down when observing targets near the zenith - the eyepiece will be uncomfortably near ground
  15. Nope. They cost almost as much as a TEC140, which is something I'd much rather have, as nice as these are. Also, since these were USN binos and therefore made with terrestrial viewing in mind, I'm not entirely sure how would their coatings compare to binos specifically made for astronomy - or in what condition would the coatings be. Years of service, salty air, crewmen who may not care that much about preserving the coatings when cleaning them, etc.. it adds up If I were a collector with a ton of money, I'd grab them in a second. But for astronomy, there are far better instruments, especially in that price range.
  16. I'd go with a 6mm Delos out of the contenders offered. In fact, I am planning on getting one in a few months (hopefully). But you really can't go wrong with a Pentax XW either. They're all pretty good offerings.
  17. Just make sure to either filter up the finder as well, or have it's caps on (better). You pretty much don't want any optical components focusing sunlight without a filter, no matter how small their aperture is. On that note, I had an idea; a kit that converts a 300mm dob into a (semi) portable solar power plant. You got the parabolic mirror, just need to replace the secondary with something that heats water inside, turning it into steam, and powering a turbine located somewhere near
  18. Try not to think about 2" as a feature that makes an eyepiece better - it doesn't by itself. A 2" barrel diameter is necessary when a wide field at certain lower powers is needed. If you put in a 12.5mm BGO on a 2" barrel (and made it work) it wouldn't get any better, optically. A 31mm Nagler or a 21mm Ethos wouldn't be able to achieve their wide fields without a 2" barrel, however. The only other real advantage is that with heavier eyepieces, the 2" barrel feels much more secure in a focuser than a 1.25" one. But it's not a case of "more inches = better"; you can use a 10mm Ethos in both 1.25" and 2" modes with no optical difference whatsoever.
  19. Are you sure you've actually locked both the RA and Dec axis? If not, it sounds like a fault in the mount itself. Did it always behave like this or is it a recent development? Did you just buy it new?
  20. More exclusive, yes, but almost entirely because of the prohibitive price. I've read detailed comparisons between Ethos and Nikon over on CN. While (apparently) the Nikon does actually perform better, by all accounts it's by a barely noticable amount, with the author often saying "I had to look which is in the focuser at times" because performance on some scopes is identical. So in car analogies I'd sooner say that the TV are Ferrari's; very expensive, very good performers that everyone's heard of, and the Nikon are something more exotic and rare like a Pagani Zonda. They didn't sell much more of these eyepieces than Pagani sold Zonda's either
  21. I get a 1.7 degree TFOV in my 17mm Ethos, and have no problems finding targets with Telrad only. It can be a bit tougher with lots of LP / narrower TFOV, but then again I tend to go for the easier targets from the city. There's a really dark observing site a bit over an hour of driving away, and that's pretty much where I do the "serious" observing. Either way, it always pays to try things out and really make sure you need the extra equipment before buying. If I went ahead with buying everything I originally thought I'd need when I was getting my first scope, I'd have a ton of unused equipment lying about right now
  22. To each his own. The point isn't that my way is the only way, it was that he may well stop using regular finders once he gets a Telrad - many people did. He may not, of course, but it would be wise to hold off the purchase a bit until he's sure he'll end up using it.
  23. Have you seen a 200p dobsonian in person? I'd say you can easily transport it in pretty much any car. Of course, if you have a really tiny car and lots of luggage, it might be a problem, but if you haven't seen one of these in the flesh you might want to check one out at a store to get the idea of it's size better. It's really not that huge.
  24. As far as I know, the semi apo was built with an idea to reduce the usual yellow tint effect of minus violet filters while still killing off CA. I think they combined a fringe killer with moon&skyglow to get the effect. As far as I can tell by the reviews (I'm thinking of buying one too) the CA reduction is a bit weaker than on, say, the fringe killer (it definitely does reduce it though), but with a much less of ayellow tinting effect. This is why this filter is on my radar, in my book the yellow tint is much uglier than the actual CA. I know it will darken the image, but I actually find this useful on planets - I often find them a bit on the bright side, a filter that removes CA and darkens the image a bit would be just the ticket to increase detail on the planets. At least that's how I see it. I don't really have a problem with CA when it comes to DSOs anyway, so I'd use it just for planets in the first place. It's definitely not the type of filter that you just screw into the diagonal and leave it there for good. Anyway, sorry, I have no personal experience with this filter, but since I do intend to get one I've spent some time hunting for user reviews and thought I'd share. I have a skywatcher evostar 120, and have no yellow tinting in the first place - no idea how it would combine with your scope I'm afraid.
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