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Alan64

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Everything posted by Alan64

  1. The planets become quite interesting to view at 150x, and upwards of course. The focal-length of your refractor, 1000mm, is used to determine which powers you want, and from this eyepiece and that... 1000mm ÷ 150x = 6.7mm eyepiece; that is, either a 6mm(167x) or 7mm(143x). This is the diagonal that came with the kit... The manufacturers often include that type of diagonal within entry-level kits for use during the day, and at night. It is a correct-image diagonal. But there are diagonals specifically for use during the day, like this 45° correct-image... ...for birds in trees, ships at sea, that sort of thing. Then, there is a diagonal specifically for use at night, a star-diagonal; for example... https://www.harrisontelescopes.co.uk/acatalog/celestron-star-diagonal.html I have that same star-diagonal myself. Here it is, on the right, and compared to our correct-image diagonals... Note the apertures of the light-ports. A star-diagonal will open that telescope up, and with a 32mm Plossl; for example... https://www.firstlightoptics.com/skywatcher-eyepieces/skywatcher-sp-plossl-eyepieces.html The 32mm would offer the widest view, and the lowest power(31x). It would assist the finder, and in locating objects to observe. Once you've located an object that you would like to see up close, you then insert a 12.5mm Plossl or a 12mm wide-angle type; for examples... Again, and from this listing... https://www.firstlightoptics.com/skywatcher-eyepieces/skywatcher-sp-plossl-eyepieces.html (80x) https://www.firstlightoptics.com/bst-starguider-eyepieces/bst-starguider-60-12mm-ed-eyepiece.html (83x) With a 2x-barlow, a 12mm can be converted into a simulated 6mm(2x-167x); or a 4mm(3x-250x) even, if you insert the 2x-barlow into the telescope first, as described and illustrated previously. A 2x-barlow, for example... https://www.rothervalleyoptics.co.uk/antares-x2-achromat-fmc-barlow-lens-125.html You also have the option of a zoom-eyepiece... https://www.ebay.co.uk/itm/SVBONY-8-24mm-1-25-Zoom-Eyepiece-Multi-Coated-Lens-Astronomy-Telescope-Parts-/283934574144 This is the chart again, and tailored specifically for your telescope; a 90mm f/11 achromat... Your 90mm f/11 achromat sits at 3.11 on the scale, and lands on the first green block denoting the Sidgwick standard for colour-correction. It simply means that when viewing brighter objects -- the Moon, the planets, the brighter stars -- you will see only a little false-colour, if any at all. This is false-colour, and seen through my 80mm f/6 achromat... Note the blue-violet rim of the Moon there. That is because the 80mm f/6 achromat is physically shorter in length... The perception of false-colour varies from individual to individual. Where some see a bit of false-colour, others may see very little or none at all. As we age, the perception of same diminishes.
  2. If in very good condition, get it. It, too, albeit un-branded, has the exact same coatings as my UOs.
  3. That's an ideal line-up for higher-powered planetary use. A 9mm is just barely a planetary. Then, since a 12.5mm is so close to a 9mm, I've always gotten one of those as well. I never wanted the 18mm or 25mm.
  4. In addition, avoid eyepiece kits like the plague. Instead, choose eyepieces carefully, one, or two at most, at a time.
  5. I have the Celestron "AstroMaster" 70EQ... There are two versions of these kits, one with an equatorial mount, and the other with an alt-azimuth mount. Your 90mm f/11 achromat falls within the Sidgwick standard for colour-correction... ...so you're good to go there. I have the same eyepieces... They're okay. They're "Kellner" type eyepieces, three-element. Plossls are four-element eyepieces, and performance-driven for most any telescope, yet economical. Where in the world are you located? I could then direct you to listings of these items, and more besides. Also, for what objects in the sky are you needing a filter? You can certainly make use of a quality 2x-barlow. That's all you need, for you can transform it into an approximate 3x mulitplier by simply inserting the barlow into the telescope first... ...and for those occasions when wanting to max out the aperture.
  6. I would think a toss-up between the two. The UOs are more comfortable(ergonomics), and fully multi-coated possibly, whilst the Baader/Fujiyama are fully broadband-coated(optical-quality). Still, you can't go wrong with either type.
  7. University Optics "Volcano Top"... Those were made by the Tani optical-house in Japan, by Mr. Tani himself. He eventually retired, and is no longer with us I'm afraid. I got my own in the early to mid 1990s. They are reputedly more comfortable, via their sloped tops. They're no longer available new, but used ones are offered for sale in the equipmental marketplaces on occasion. Then, many of the old and wonderful optical-houses of Japan, some if not many employing only a handful of workers, were swept away by the tsunami of 2011. Later, I got these Baader Abbe orthoscopics, and the same as the current Fujiyamas... Those two marques are/were manufactured by Masuyama of Japan. The Baader examples were sold for only a few years, or less.
  8. Most any eyepiece barlows well, if with a quality barlow.
  9. The "Starbase" eyepieces are made by an optical-house in Hanamaki, Japan; not Takahashi. Takahashi has never made lenses, only optical-tubes and mounts. The fluorite-doublet within my Takahashi FS-102 was made by Canon-Optron, for example. The only ones I'd be interested in having are the 6mm, and perhaps the 9mm. These eyepieces excel on small, tight(non-diffuse) objects; the Moon, the planets, and double-stars.
  10. Oftentimes, it's quality you're after, rather than quantity.
  11. I couldn't stand it any longer, not knowing for certain, so I removed the focusser... Incidentally, the cover-plate, for securing the pinion-gear against the rack, was not installed evenly. It didn't take much to correct it, but there was no excuse for that. The optical tube has three baffles: 1, 2, 3... I would like to retain those, but I would have to mark their positions, remove them, then flock them along with the rest of the tube. The fitting for the attachment of the slow-motion control rod... Those are machine-screws, therefore the six holes are threaded, and just as I expected. Set-screws will fill those in nicely. I will be making a light-shield for the focusser of this one, and just as I did for the Antares 805...
  12. It turns out that the tube-rings were shipped via "UPS Surepost" <grumble grumble>, but still on time. Thankfully, they have "Arrived at Post Office", locally. I feel a trip to my local hardware at the county-seat coming on, for screws and such to attach the rings to the bar, and for set-screws to fill the six holes in the tube.
  13. Refractors differ from reflectors(Newtonians, Newtonian-Dobsons, Cassegrains) , and in very important ways. Don't think for a moment that you have to have an 8" or 12" refractor, which has nothing whatsoever to do with price, absolutely not, for the refractive experience stands alone, and regardless of aperture. I have reflectors, several types, up to 150mm in aperture. I have a Newtonian at 200mm, but I've yet to observe with it. But there's just something about my refractors that keeps me coming back for more, from the beginning, to the end... Smaller refractors are more fun than you can imagine.
  14. I don't know if the question has been asked: have you ever owned or observed through a refractor? I've seen globular-clusters through this wee 50/600 achromat... But for those who have never experienced a refractor, 80mm is the minimum to suggest; yea, even a 70mm is praiseworthy... A reasonably-priced gamble... https://www.firstlightoptics.com/evostar/sky-watcher-capricorn-70-eq1-refractor.html
  15. It sounds to me that you need a new star-diagonal. It appears that the star-mirror diagonal that came with your Bresser kit... https://www.bresser.de/en/Astronomy/Telescopes/BRESSER-Messier-AR-127S-635-EXOS-1-EQ4-Hexafoc.html ...is exactly like the one that came with my Explore Scientific 127mm f/15 Maksutov... However, you can make use of a 2" star-mirror, and thereby a 2" eyepiece or two. I don't understand what you mean, precisely, as to an "extended prism". You can certainly get a 90° star-prism diagonal in the 1.25" format. I think it's great that you have an observing pal.
  16. Congratulations are in order. Your new DZ will be quite the eye-candy machine, and just as my own FS-102 has been... That one was produced in 2003, and the last example in 2005. Takahashi then took a break from manufacturing the 100mm+ fluorite-apochromats, and for several years, up until about 2012 or 2013. The new ones are lighter in weight, whereas my older one is a veritable porker. Consequently, you'll be likely to observe with yours, and more often than I do with my own. Enjoy.
  17. I have decided that I will not be wanting to keep this telescope on its yoke-style mount. I will need to remove these fittings, of metal surprisingly, and fill the holes with set-screws... Back in June, I had gotten a new old-stock Meade LX70 EQ5-class mount. It came with this dovetail-bar, and 150mm in length... That will do quite nicely. I have also ordered tube-rings, 100mm ID... Those are scheduled to arrive by this coming Friday. Incidentally, this OTA is the same as that of the Meade "Infinity" 102mm kit, and with an AZ3-class mount. Would that I might've run across just the OTA of that kit. There would've been less holes to fill, but no matter really.
  18. First light, and with the eyepieces and other that came with the kit; during the day, although there's not much to see: the usual power-transformer in the distance... ...and trees, lots of trees... Surprisingly, I saw very little false-colour. Those images were taken with the bundled 26mm MA(modified-achromat) eyepiece(23x). Then, at night; Jupiter, at 133x(the bundled 9mm MA combined with the 2x-barlow)... The false-colour is quite apparent there, but then Jupiter is awfully bright. In addition, the barlow most probably contributed as well. I don't know how I did it, with the mount as it is. Saturn, at 133x... Miraculous, that shot was, and out of eight attempts. The view, live, was, as always, considerably sharper. The Moon through the 26mm MA (23x)... I had to set the camera to sub-second exposures, as the light gathered was a bit overwhelming, particularly that from an almost full Moon. Through the 9mm MA(67x) only... The view at 133x was not as sharp, not with these kit eyepieces and barlow, but not too bad. I do have those better to use with the telescope. This is where I drew back away from the telescope, and took a shot of the Moon's reflected light shining through the eye-lens of the 9mm MA... That completed the first light for the telescope. This doublet is hereby declared to be worthy of a right good blackening, and with new spacers perhaps. I am in great earnest to do so, along with the blackening and flocking of the tube throughout, down to the last square millimetre. I may now banish the bundled eyepieces, diagonal and barlow back to their box, and for all time, for I saw some graininess at one point using these items. They're practically identical to what came with my Meade "Polaris" 114mm f/8 Newtonian and EQ-2 kit... That barlow introduced considerable false-colour, and to an otherwise 100% apochromatic instrument. The eyepieces are just as bad, the bottom of the barrel, stuck to it even. But that's to be expected. As with all of these entry-level kits, what we're only and really after is the telescope, in the end.
  19. Photo-shoot... The kit seems rather toy-like there, and here... Unfortunately, the legs should always be extended to get the telescope up to a suitable height... It's not the worst in stability, but not that far ahead. This achromat will make for an excellent terrestrial spotter during the day, and perhaps at night as well; for surveillance.
  20. The OTA... Only a single scratch was discovered... That came as no surprise whatsoever, as I've bought from this seller before. I'm just grateful that that was the only one. The specifications-label; Meade seems to have always had the prettiest ones... Those of Celestron are downright spartan... The objective... Note the deep plum-like colouration of the doublet's coatings. Then, we have the green... ...four inches of delectable, luscious, unobstructed, refractive goodness. I knew even before, prior to purchasing, that this achromat came with a 2" all-metal focusser... ...and with a 1.25" adaptor. That's the draw-tube racked fully outward, and ideally, short. There should be no stopping-down of the aperture within this telescope as a result.
  21. The mount... The yoke is of metal, and quite rigid. It's rather reminding of a Tele Vue yoke. The hub to which the yoke attaches is of metal as well. But the legs, the spreader, and the tray, simply do not equal that above them. Then, the legs may be upgraded, to something more substantial, of wood perhaps. The eyepiece tray... ...and exactly the same as the one that came with my Celestron "PowerSeeker" 127EQ. Interchangeable, they are. Note where the telescope attaches... With this type of mount, at this price-point, it helps to add heavy-duty springs, and washers, to where you might be able to omit the slow-motion rod even... But only if you intend to keep the OTA on that mount.
  22. The un-boxing... It's so very difficult to source a 102mm f/6 achromat these days; pity, that. Synta offers one under their "Celestron" marque, the "AstroMaster 102AZ", but with a plastic, wonky, "tongued" focusser, and jepardous for an accurate and precise collimation. Curiously, however, Synta does not offer one under their "Sky-Watcher" marque; only at f/5 rather, and much too short for the astronomy gods to so bless. The accoutrements... ...and what was not included within the "Good" kit... The eyepieces, the barlow and the red-dot finder are like new. The star-mirror diagonal, however, appears to have been cleaned with a finger and spittle at some point in the past... That was easy enough to restore, and happily, with no scratches evident... ...but what a cheapie. Incidentally, I did not pay the extra $25 for those. I paid it in the hope of hopes that the OTA would be in "excellent" condition, rather. The "smartphone" adaptor, surprisingly of metal, and with nylon thumb-screws for attachment to an eyepiece... Perhaps it should've been made of plastic, but not like this Explore Scientific/Bresser adaptor... In any event, in that I do not own nor use a "smartphone", that'll be about as useful as <insert here> on a boar. Would that I might alter, modify it, and to work with my point-and-shoots...
  23. I fixed the camera. It was a thing or other. Glamour shots... The contents are not necessarily original to that box. The kit was a return, to a Costco, a discount, wholesale warehouse, which requires a membership-fee. Costco then sent the return to Meade, and then Meade sent it to said seller for liquidation... ...a 102mm acxhromat, at f/6; f/5.9 actually, but I made an exception. We do what we can these days.
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