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Alan64

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Everything posted by Alan64

  1. You have a Sky-Watcher(Synta) 130mm f/7, and I have this Meade(Ningbo Sunny)114mm f/8... Both of our telescopes have a 900mm focal-length, an EQ-2 mount, and spherical primary-mirrors. At the longer focal-length of my own, I have been told that the telescope is at 1/5th-wave if perfectly spherical. Therefore yours, at f/7, should perform within Rayleigh's 1/4th-wave criterion as well, and diffraction-limited. But it must be collimated well. Mine, fresh out of the box, gave me practically tack-sharp views. "Diffraction Limited" is stated within the specs of the Orion-of-California variant of your own, the Orion "SpaceProbe" 130, and also made by Synta. In order to use an inexpensive motor-drive with your mount, you must adjust the mount, and to where you can twist the RA worm-shaft with your fingers, and with little effort... Else, the plastic gears and their teeth within the drive will break and crack, and the motor itself can burn out. These mounts generally arrive bound-up and tight. If yours seems a little too tight, loosen it up. The mount is a mechanical thing, a machine, and consisting of nuts and bolts to hold it together.
  2. Now that's lovely. In initial appearance, it hearkens back to the classical Cassegrains.
  3. It appears that you know and prefer the Maksutov design, therefore barring the acquisition of a 250mm... https://www.robtics.nl/popup_image.php?pID=3005 ...and in that you already have a 120mm, I would go with the 180mm. A 150mm may not give you the "pop" you're looking for after having observed with the 120mm. I've always believed in placing the wherewithal at hand into the telescope, then to to get the bits and bobs for it over the weeks and months, and years even. I prefer Maksutovs over Schmidts, and will be getting my own in future.
  4. Incidentally, I found this 90mm refractor at a thrift store recently, and in dreadful condition... No hand-controller, and busted up right good. I couldn't even rack the focusser in and out, as it was much too loose, like it was going to fall apart. I don't want to know how that had happened. The price-tag... Well, at least they wrote "Refracting Telescope" on the tag. I'll give them that.
  5. I see what you're referring to, and understandable, but could the 22mm and 11mm be referring to the eye-relief instead? Granted, that would be odd in their including that information. Much mysterious, but after investigating further, an Amazon member answered one of the questions posed about the kit, here... https://www.amazon.com/ask/questions/asin/B017NHHZ4G/3/ref=ask_ql_psf_ql_hza?isAnswered=true "Yes, I got the Celestron 93230 8 to 24mm 1.25 Zoom Eyepiece, it works well with the scope as well as the Barlow Lense. Haven’t had any problems with it at all, and it’s very convinient not having to swap out lenses for different magnification. Highly recommend." - William Bartnik Now, I have seen new kits online bundling .965" eyepieces, in the past few years, but thankfully very few and far between. Incidentally, the Zhumell .965" oculars are defunct. These are the only decent ones I know of sold new in the U.S., and I have two of them myself... https://optcorp.com/collections/0-965-eyepieces
  6. https://cosmicpursuits.com/1943/how-to-see-averted-vision-and-dark-adaptation/
  7. This is the telescope in question, and it uses 1.25" eyepieces and accessories... https://www.toysforscience.com/shop/gskyer-instruments-infinity-70mm-az-refractor-telescope/ It comes with a "shorty" barlow, and a rather poor one at that, which have always been of the 1.25" format.
  8. Any eyepieces or accessories(like a star-diagonal or a 2x barlow) that are purchased for the present kit can be used with other telescopes that may be acquired in future. Telescopes come and go, but eyepieces and such are like luggage, and for life. When you buy a 2x barlow, it's a one-time acquisition. You'll never need another, unless they're lost or spirited away. The same goes for the rest. I, too, suggest a star-diagonal, for use at night, and a 32mm Plossl(22x). The 32mm would provide your lowest power and the largest view of the sky; to get your bearings, and for the ease in hunting for this object and that. Once an object is found, you may want a closer look at it. You then swap the 32mm with a 12mm(58x) combined with a 2x barlow, and for a simulated 6mm(117x). That would be about as high as you might go, for now. Examples of same... https://www.365astronomy.com/32mm-GSO-Plossl-Eyepiece.html (22x) https://www.365astronomy.com/12mm-GSO-Plossl-Eyepiece.html (58x) https://www.365astronomy.com/GSO-2x-Barlow-2-Element-Achromatic-Barlow.html (117x, with the 12mm) If the budget will not allow, a barlow can wait. A star-diagonal... https://www.365astronomy.com/Celestron-Diagonal-Star-1.25-in.html The word "star" tells you that it's for use at night. The original diagonal that's missing is an Amici, or erect-image, and for daytime/terrestrial use; birds in trees, ships at sea, that sort of thing. Replacements of that type are sold online as well. If you only want to "jump start" it, there are budgetary options for everything but a 32mm Plossl, on eBay and the used marketplaces online.
  9. Quite right, as you want to have experience with the telescope and its workings beforehand. It was a year of observing before I began my own. You would be without the telescope during the renovation, of course, but then you'd have the improved views of which to look forward once it's completed. In addition to the flocking, I use matte, chalkboard-black spray paint, and I sometimes spray the paint into a condiment lid or other and apply the paint with artists' brushes, when applicable. Within my link posted previously, I later abandoned the idea of flocking the drawtube of the focusser. Its interior might need to be repainted however, if desired, and upon inspection. The "black" paints used by the manufacturers are nowhere near the blackest available. The goal is to make the front entry and the entire interior of the telescope up to the eyepiece as inhospitable to stray reflections of light as possible. If I had to go back in time, and before my own was performed, I wouldn't observe with it until after I did it all over again.
  10. Actually, you'd need to take the Newtonian completely apart, for a proper job. Ah, but no more ghosts and goblins within the field-of-view. When observing an object, the contrast would be noticeably improved, to see its details more clearly, and the background sky surrounding the object would be blacker, instead of just grey-black. Have a look at what I did to my own... https://stargazerslounge.com/topic/262096-deadening-a-150mm-f5-newtonian/ Any questions? I'd be glad to help.
  11. Ah, those may due to ghosts and glares, those in turn caused by reflections along the light path, whether within the eyepieces, a barlow if applicable, or the telescope itself. Have you ever heard of blackening and flocking the interior of a telescope?
  12. Yes, that's due to the lovely spider-vanes supporting the secondary-mirror, just inside the front of the telescope... It is possible to minimise, perhaps to even eliminate the effect, and with a single curved vane... https://garyseronik.com/how-to-build-a-curved-vane-secondary-mirror-holder/ With my own 150mm f/5, it's particularly annoying when observing Jupiter, or Mars during its last opposition, but a variable-polariser works a treat in those instances, and perhaps for the brighter stars as well... https://www.365astronomy.com/variable-polarising-filter-1.25-by-ovl.html The object will be dimmer, of course. In the case of Jupiter I was finally able to see the planet's features with the filter integrated.
  13. The nuts on the inside of the tube are six-sided, of course. I took a wire clothes-hanger and formed a wrench out of it. You simply bend the end of the wire with pliers into a six-sided loop, and at about the size of the nut. You then hold and keep the nut from moving with that whilst unscrewing the bolt on the outside which requires a hex-key; simple. You can loosen the screws holding the focusser in place, tilt the body of the same until it's on-axis, then batten the screws back down. However, I would suggest pursuing a simpler focusser, and as I'm planning to do. 70mm refractors are quite commonplace nowadays. Incidentally, I got mine up to 225x on Polaris, and with little image breakdown as I could still clearly distinguish the first-diffraction ring of the star. The star was quite dim at that power, per the achromat's 70mm aperture, but still visible.
  14. Ah, you have the same one as I do. It's sold in the U.S. as the Meade "Polaris" 114EQ... I've found it to be quite a good kit, but for Tokyo and its light-pollution the more aperture the better, to a point that is.
  15. Hello Paul, and welcome. I can't imagine that you'd need any filters for the telescope, but you certainly could use some better eyepieces. But before any recommendations can be made, we would need to know the diameter of the barrels of the eyepieces that came with your new kit. The current minimum, and of what is readily available, is of a 1.25" diameter. The old standard is of a .965", or 1" diameter. If the .965", you'll be hard-pressed in finding eyepieces of that size. Here's an illustration of both types...
  16. You can take casual snapshots through any eyepiece and through any telescope, but only of the brighter objects in the sky, and with a small point-and-shoot camera, or with that of a so-called "smartphone". I took these, shown here within a collage, simply by holding said point-and-shoot up to the eyepiece and snapping the shots... That's just how each appeared during a live view, with my eye and eyepieces, and through this 150mm f/5 Newtonian whilst mounted onto that alt-azimuth... Of course, the objects looked much better during the live view, with my own eye. But if you're wanting to take pictures with a camera attached directly to the telescope, that will require a large, heavy and substantial tracking-capable mount, along with a smaller telescope; for example... https://www.firstlightoptics.com/reflectors/skywatcher-explorer-130p-ds-ota.html https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-eq5-pro-synscan-goto.html But if you considered that mount, this one would be better in the long run... https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-heq5-pro-synscan.html This one, even better than that one, perhaps... https://www.firstlightoptics.com/skywatcher-mounts/sky-watcher-heq5-pro-with-rowan-belt-mod-upgrade.html That kit would be a bit overkill for visual use, also with a smaller aperture to boot; but for astrophotography it's at a minimum. Read about what you might accomplish with a 130mm f/5 Newtonian... https://stargazerslounge.com/topic/210593-imaging-with-the-130pds/ For visual use only, a Newtonian on an equatorial mount is for longer periods of observing a single object. The mount, if simply motorised, can also cause that object to stand still there in the eyepiece, and as if time itself had stopped. If you prefer to flit from one object to another in the space of 15 minutes or so, then choose an alt-azimuth mount. Your eye and mind isn't really bothered if the image in the eyepiece shakes and jiggles, but a camera attached in place of your eye and eyepiece simply will not stand for it, and will result in blurred images. A camera must be held firmly in place, like a rock, when tracking a dimmer object over a long period of time, whilst collecting the light from same, or else just one little shake or jiggle will ruin the image.
  17. No apologies are necessary. I got these tube-rings online, here in the U.S.... https://agenaastro.com/agena-telescope-tube-ring-2-9.html ...and I removed the dovetail-bar from the optical-tube and attached the rings to it... I got longer bolts locally, metric, just like the original, short ones... The bar is rather short in its fixed position upon the tube, and therefore quite limited in being able to balance same when adding the diagonal, eyepieces, a barlow perhaps, and other accessories. Incidentally, I loathe the focusser... ...the body, shown there, specifically. I plan on replacing it in future with one that's a bit less "creative" in design.
  18. The equatorial mount will allow you track any object, and manually with the RA slow-motion control knob. If you ever want to cause an object to stand still there in the eyepiece, as if time itself had stopped, you can motorise the mount. That refractor is a keeper; and one that you'll never grow tired of, especially as it can easily travel with you, short or long distances, but you'd probably want an alt-azimuth, a travelling mount, for those times. Congratulations., and enjoy.
  19. It's marginally better, at least, than the Zennox variant that you had inquired about previously, particularly in so far as the tripod. Both will have spherical primary-mirrors, and should perform well at that longer focal-length.
  20. The leg assemblies are now ready to be dyed; and yes, the brass is quite flat and conformative to the wooden surfaces...
  21. On the flip side of those overlays, the brass, but the edges of the wood must be dyed first, as there'll be no dyeing where that epoxy touches; same with wood-glue, but I didn't want to dye around the maple overlays, as the glue might not hold in that instance. Why take the chance. I cut the dye, half to half, with denatured-alcohol, and it's still a bit dark... I may use two parts of the alcohol to one of the dye, but I'll need to test that first.
  22. I did the last three in one fell swoop, whatever a fell swoop is. Now, those overlays are lighter than the legs, and I want them inconspicuous, so they'll get a double dose of the dye... Now for epoxying the brass...
  23. Three are not done... ...but three are. You can't rush these things, you know.
  24. The speed, at what gigahertz does the processor, or CPU, run. Online, I'm seeing 1.0 Ghz for that particular model... https://www.amazon.com/Asus-X102BA-Touchscreen-A4-1200-Laptop/dp/B00FAUGFTA Incidentally, Windows 8 came with my Lenovo laptop, but I promptly erased it and installed Windows 7; then later, Windows XP over that. I'm a bit old-school in that sort of thing.
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