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SpaceWalker

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About SpaceWalker

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  1. The former is true except the Moon, the latter is false. If you like observing Mars and especially Jupiter the Baader Moon & Sky Glow filter is a must, IMO. Although, for Mars a Magenta #30 works better. For the Moon you'd better observe at least halfmoon and pump up magnification significantly that reduces brightness. Any filter, neutral or polarizer, bounces/disperses some light and reduces sharpness, do you want this trade off? As John explained above the Baader M&SG is a broadband filter and doesn't work on nebulae etc. IMO, for the emission nebulae you'd better get Astronomic OIII or at least Baader visual OIII filter. For the reflection nebulae and galaxies no any effective filter exists other than "gasoline filter" (fill up gas tank and drive to a dark area ).
  2. You may want to look into Al Nagler's advise for 8" SCT users. Not necessary you should buy TeleVue, but you can get an idea. http://www.televue.com/engine/TV3b_page.asp?return=Advice&id=97
  3. Takahashi LEs seem still available new, but they cost inbetween TV Delites and Naglers T6 ?
  4. If anybody interested. Ernest has bench tested Mark III and found it is 1) poorly corrected off-axis at all settings; 2) shrinks FOV pretty fast, e.g. from 72* at 8mm to plossl-like 52* at 16mm and just to ortho-like 44* at 24mm, so it's useful mostly within 8-12mm. And I also *suspect* ? it may have EOFB (Edge of Field Brightening) like other zooms, even expensive ones (e.g. Leica). IMO, like any other, even cheaper zooms, it's good for 1)planetary observations since allows to select optimal magnification within seconds instead of wasting time for pulling back and force separate EPs; 2) as noted above, good for solar observations; 3) very useful for fast dialing up optimal magnification for faint fuzzies; 4) overall good grab-n-go eyepiece. But IMO, it's not a serious competitor for mid-range (e.g. ES68/82/100) or premium (e.g. Pentax, Nikon, TV) eyepieces for DSO observations especially in faster scopes, what actually John has reported above. To each its own. ? But I agree, overall good addition to one's EP collection, nice to have it in your EP case.
  5. Nice catch I missed it. Indeed, the 42mm LVW with FS of 46.5mm provides the widest view possible in 2" focuser. In 120/80 refractor it should give ~2.8*TFOV assuming no distortion. BTW, have you performed timing test to be sure it really shows 3.02*TFOV? I suspect that 72* at 42mm is too optimistic for a 2" focuser even though if the EP would be capable, e.g. in 2.5" focuser
  6. AFOV has nothing to do with TFOV. An eyepiece with 46mm Field Stop, assuming that the OPs refractor FL= 960mm, will give TFOV=2.7*. The closest out of 100* AFOV eyepieces, a 25mm ES100, will give TFOV=2.4*. All the others suggested by you will give narrower view.
  7. I observe mostly in a Red Zone and, frankly, I don't know any EFFECTIVE LP filter. Any polarizer is useless for LP reduction. Sometimes UHC can help but not much. As they say, the best is a "gasoline filter", when you load full tank and drive to a dark sky area . Or wait for a moonless night. Variable polarizer is good for closely located objects different in brightness like Sirius A and B etc. You can cut the price by getting 2 inexpensive single polarizers e.g. from eBay or so. Attach one to a diagonal or 1.25/2 adapter (in reflector) and the other one to eyepiece, or better, to an extension tube and you can change eyepieces on the go.
  8. Any eyepiece with Field Stop of 46mm. For example, depending on your budget, 41mm TV Panoptic, 40mm ES68, 40mm WO Swan or similar.
  9. IMO, the best budget planetary eyepiece is a decent Zoom + Barlow. This combo is relatively inexpensive and very flexible, you can reach appropriate magnification perfectly matching the seeing conditions just in seconds and, therefore, catch rare moments of perfect seeing which usually can last 10-20 seconds. Think about that. If you are a budget observer you can't avoid using Barlow or you must pay extra for fixed focal length eyepieces, there is no free lunch . I can't recommend 66*AFOV SWA eyepieces for planetary, they are not good for that, IMO. But if you still want fixed focal length eyepiece, I'm second to Davesellars, the 6mm BCO or 10mm BCO+Barlow would be a good choice. But eye relief especially in the BCO6 is very short. I have both of them. You can also try getting a 5mm BST Stargutder, many observers are happy with it. If you have a chance buy on the used market, it'll save you a lot of money. http://www.teleskop-express.de/shop/product_info.php/info/p463_Baader-Classic-Ortho-6mm-1-25--Eyepiece-with-rubber-eyeshield.html https://www.firstlightoptics.com/bst-starguider-eyepieces/bst-starguider-60-5mm-ed-eyepiece.html
  10. There are indeed some useful threads on CN discussing 100*AFOV eyepieces including the Lunt. For those who are interested I'd suggest to check out the thread *Lunt XWA 9mm* on CN, especially posts ##9 and 11 by vkhastro1. https://www.cloudynights.com/topic/563666-lunt-xwa-9mm/
  11. Manufactured by Long Perng. Some variety of outfits. But the optics should be the same. http://www.longperng.com.tw/goods.php?act=list&catId=20&page=4
  12. John is right as usual, they seem are well-known 5-element Masuyama-like. For example, there is an older thread on CN discussing Kasais https://www.cloudynights.com/topic/304722-kasai-astroplan-eyepieces/ IIRC, Bill Paolini posted on CN he liked longer FLs better than TV Plossls and vice versa for shorter FLs.
  13. John, Thanks for sharing your experience. I knew that the Antares Orthos, UO HDs and BGOs are considered pretty much the same optically except coatings, but haven't had a chance to try BGOs in person so my gesstimates based on multiple positive reviews across the web like from Alvin Huey (FaintFuzzies.com) etc. It seems the grass as usual is greener on the other side of the fence . As for TV Plossls some experienced observers claiming that the older Plossls provide brighter images, for example here (http://www.astronomyforum.net/telescope-eyepieces-forum/224964-televue-made-taiwan-2.html) J.Gardavsky says that about the older 13mm and 21mm TV Plossls. I can guess that well known Okulartransmission(http://www.amateurastronomie.com/Astronomie/tips/tips3.htm) data from Markus Ludes showing high light transmission in the TV Plossls based on the older TV EPs.
  14. Excellent BGO collection, congrats on your find! Any owner of a good refractor can dream about it. With the time I more and more appreciate Orthos over Plossls. Even in my Dob they work really great, I don't care about the narrow field. Maybe it's just me, but Orthos show views slightly sharper than Plossls with more contrast
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