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Alan64

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Everything posted by Alan64

  1. I've never gone above a 12.5mm in an orthoscopic. I probably should've stopped at the 9mm even, but 12.5mm is closer to 9mm than an 18mm, so I went ahead and got it... To me, that's a well-rounded set of orthos, from 5mm to 12.5mm. Orthoscopics are best for critical high-power observations, and with the telescope on a motorised mount, so that the object doesn't drift out of sight. Orthoscopics have a narrow field-of-view, generally an AFOV of around 43°, and rather short eye-relief. If your CG-3 mount is not motorised, which it can be after adjusting/loosening it up(of the utmost importance), then you may wish to consider eyepieces at 60° AFOV and perhaps wider even. As you go up in power, the telescope, and the rest, has to work harder to produce sharp, pleasing views. That will require a spot-on collimation. I don't think that the primary-mirror of the "AstroMaster" 130/650 is centre-spotted. If not... https://garyseronik.com/centre-dotting-your-scopes-primary-mirror/ That will require removing the primary-cell from the back of the telescope's tube, then to use a Cheshire and/or a collimation-cap to align the optical-system. You may already know how to collimate a Newtonian, I do not know. For your lowest power, for the hunt, a 32mm Plossl serves best. The rather short focal-length of the telescope, at 650mm, will probably require another 3x-barlow, albeit one of better quality; that is if high-powered observations are to be regularly enjoyed.
  2. That's quite a low-profile focusser as it came originally. If you're referring to those of the Chinese eBay listings, I've seen them. They appear to be viable, and of metal, but again it would need to be shortened somehow, rather drastically I'd say, and yet another DIY project if possible.
  3. The inner surfaces of the ends of the tube were matte-blackened up to the edges of the strips of flocking... Now to prime and gloss-blacken all the rest where needed, including the primary-cell mounting-extensions, then the tube itself will be completed.
  4. Yes, you'd be able to compare the two apertures, right-angled or no. I don't have a right-angle finder-scope myself, and I need one for my 127mm Maksutov. It's not much larger than your catadioptric, but it has a focal-length of 1900mm(!). I'm seriously looking to converting a short 70mm refractor, very short, into a finder-scope, as that Maksutov is going to need all the help it can get when perched upon my manual mounts.
  5. The larger the tube, the greater the need for a plate. The plate also gives peace-of-mind, especially if the finder-scope is bumped hard and/or the user is indeed in the habit of using it as a handle. The latter can occur in an instant, without even thinking. Larger, fender-type washers on the inside, before the nuts, would also afford a bit of rigidity. The planets and other bright objects can certainly be found easily enough at 9x. A 9x50 is only good for deep-sky hunting due to the 50mm aperture; certainly not the 9x magnification. Of course, as the aperture increases, so the power; can't get past that. Although I do wonder why Synta is such a stickler for a 9x50 instead of an 8x50.
  6. Bortle-5 is quite good. I'm under 4 to 5 myself. You can catch quite a few deep-sky objects with your telescope under those skies. I tried to find an 8x50 there in the UK. There are a few, but for a considerably-higher price, particularly compared to here in the U.S. where I'm located.
  7. EDIT: That somewhat, but to a greater extent the bulk, and it is worth the addition if you feel you'd benefit from the larger finder-scope. With a 32mm Plossl, 31x is the lowest power you would have to assist the finder-scope in hunting for objects. 31x is not particularly low in power, but it is within the low-power range. So that's where the larger finder-scope would compensate. But then, the 6x30 is at a lower power, 6x. It just doesn't have a particularly large light-gathering aperture. There are those that prefer a 6x30 over a 8x or 9x 50mm, and for that lower, 6x power. But if you observe under considerable light-pollution, then the larger finder-scope would indeed be of greater benefit. I suspect that larger finder-scopes evolved as artificial-lighting increased, particularly near or within the cities of the world.
  8. https://www.365astronomy.com/SkyWatcher-6x30-Right-Angled-Finderscope.html However, right-angle finder-scopes are more common and popular in the 50mm size... https://www.firstlightoptics.com/finders/astro-essentials-9x50-right-angled-erecting-finderscope.html With your "Bird Jones" at a 1000mm focal-length, and just as my own, ours would benefit from a 50mm, whether an 8x50 or 9x50 RACI... Those are attached to my "Bird Jones" reflector within those images. This is my own... If collimated well, they are quite good for the medium-to-high powers, as befits a longer focal-length combined with a spherical primary. If you'd like to consider a 50mm RACI, the telescope's finder-base should be reinforced, if not already. I added a steel plate to my telescope, underneath the base on the inside of the tube... For a 6x30, such is not really necessary. Also, it could be that your finder-base is already reinforced, I do not know.
  9. You don't want a 40mm, as the background sky surrounding an object would be greyer, washed-out. A 32mm is the standard for the lowest power, generally, and with many different sizes and types of telescopes. With that lowest power, aside from augmenting your finder in hunting for objects: the star-fields of the Milky Way, the Pleiades, and a bit beyond the core of the galaxy in Andromeda; the largest objects in the night sky. Incidentally, here are a couple of simulators... https://astronomy.tools/calculators/field_of_view/ https://www.stelvision.com/en/telescope-simulator/ My Orion "StarBlast 6" came with the same 25mm Plossl as your own, in addition to a 10mm... If that's the 25mm mentioned, it is a 52°, not a 60°. I have a few 25mm eyepieces, and that came with this telescope and that, but I never use them; too close to a 32mm. I prefer a 20mm as the next step down from a 32mm. This is a 20mm 68° that would work very well with your telescope, at f/8... https://agenaastro.com/gso-20mm-superview-eyepiece.html (60x) ...and one that I have here in the household. That's the nice thing about a longer focal-length telescope, as you don't have to break the bank in getting corrective, costly eyepieces for a good time at the helm.
  10. Thank you Robert72. Oh, that's just a bit of comedy there.
  11. The flocking of the optical-tube is completed, although I do need to matte-blacken just in front of the edges of the flocking at both ends of the tube all round... With the cowling and primary-cell attached, along with their mirrors... ...lovely, lovely, lovely. Note the light peeking through at the back.
  12. One more to go... The last strip applied, and very last one that I'm about to install, each strip is in two pieces, as I'm using scraps to avoid having to cut into my main roll.
  13. I'm taking into consideration that the OP is wanting to dabble in astrophotography, is all. The tube-rings of a Newtonian mounted upon an equatorial do allow for the rotation of same. In the case of a 200mm f/5 however, one would want to effect an easy modification so as to prevent the tube from slipping out of its rings whilst so doing... http://www.andysshotglass.com/wilcox_rotating_rings.html That would enhance visual use and afocal-photography(through an eyepiece).
  14. The second section...<cough cough cough wheeze>...has been installed...
  15. The first section of the flocking has been installed. This time round I wanted to straddle the tube's seam with a single piece...
  16. I suppose that depends on how large of a telescope. For about 50 years, behemoths were produced in California, like this 300mm f/5 for example... ...and yes, they were quite costly. If you look closely, that particular sample came with a right-angle finder-scope; fancy that. But then, John Dobson came along, saving the day, and by putting that particular manufacturer out of business. That manufacturer eventually offered "Dobsonians" of their own making, but it was too little too late. If one desires a Newtonian larger than a 200mm f/5, then it is best to have it mounted upon a Dobson alt-azimuth. Incidentally, Dobson did not invent the mount that bears his name. No, rather it was another who invented the mount, and long before Dobson... Nonetheless, there is one thing an equatorial can do that a rocker-box cannot, and that is to cause an object to remain perfectly still there in the center of an eyepiece, and as if time itself had stopped.
  17. Before John Dobson came along with his rocker-box, Newtonians were routinely mounted upon equatorials, for decades. Equatorial mounts track objects far better than rocker-boxes, if such is of great importance to the user. Observing at the higher powers is what a telescope is for in the first place, and where ease in tracking is paramount.
  18. The EQ-5 is a manual equatorial, which can be upgraded with a single motor for the RA(tracking only) and inexpensively, or a go-to kit, in future. The EQM-35 is a smaller EQ3-class go-to mount. A 200mm instrument would be out of the question. A 150mm would be doable for visual and casual imaging, yet with a 130mm as the ideal.
  19. In the long run, you'll be glad you had gone with the HEQ-5. Incidentally, you can buy that mount separately, as well as a 150P-DS, if you feel that the 200P-DS might be too large.
  20. Indeed it does. I believe it to be an EQ3-class, and per Bresser's own website.
  21. http://www.scopestuff.com/ss_fm30.htm ...although a bit pricey. I'd want the aforementioned for my Maksutov.
  22. I can't help but to want to bypass the usual fare, and then to wonder as to viability of this 70mm f/4 achromat. With a 32mm eyepiece inserted, 9.4x... https://www.barska.com/30070-225-power-starwatcher-telescope-by-barska.html
  23. That one appears to be just as long as my 6" f/5 classical-Newtonian... In the case of your own, the design was perhaps lengthened to minimise coma at least; and yes, spherical primary-mirrors do exhibit such.
  24. Hmm, Telescope House has the mount listed as an EQ-2. It does appear to be an EQ3-class equatorial rather.
  25. Hello, and welcome, To answer your questions... 1. You may want a variable-polariser... https://agenaastro.com/celestron-variable-polarizing-filter-1-25-94107.html That way, you can adjust the level of brightness/dimness, when observing the Moon, Jupiter and Venus. In the case of the planets, the filter would allow you to see their features better, and more pleasingly. There are many DIY mods that can be performed on a Newtonian, and to improve its performance within said environment. A 6" aperture is capable of 300x, under ideal seeing conditions, particularly when observing the Moon. The planets will have to make do with less magnification, say, 200x or so. Of course, that will depend on a number of factors: seeing, collimation, et al. 2. At f/8, and with a focal-length of 1200mm, your lowest power, for hunting the dimmer, deep-sky objects, will be limited to 38x, and with a 32mm Plossl. I'm afraid that that's not what you'd call a low-power suitable for the hunt, but it is what it is, and will have to do. In hindsight, the Sky-Watcher 6" f/8 Newtonian-Dobson comes with a 2" focusser, which would have allowed for a larger view of the sky with a 2" 32mm or 38mm eyepiece... https://i.imgur.com/zZtDa3w.png ...so much for that. 3. The planets become interesting at around 150x. 1200mm÷ 150x = an 8mm eyepiece. You may want wider-angle eyepieces, especially for the higher powers. At f/8, you can choose from among quite a few that are under $100. This one would produce 185x with your telescope... https://agenaastro.com/meade-series-5000-6-5mm-hd-60-eyepiece.html 4. https://astrozap.com/collections/solar-filters/products/baader-solar-filter?variant=8277637922860 You would want the 174mm-184mm, and per the measurement I just made of my Orion 6" f/5... Incidentally, had I to do it all over again, I would've gotten a 6" f/5 with a 2" focusser; spilt milk that is. You can't be too careful when observing the Sun. Take all precautions, and then some. 5. At 48x, with your 25mm eyepiece, there are quite a few deep-sky objects to observe. Some may want more magnification; others not. I would suggest downloading Stellarium... https://stellarium.org/ It's a great planetarium, and it's free. Enter your location and it will show you what's in the sky, day and night. Be sure to toggle the deep-sky object icon... You can plan an evening's observations with the program. Cheers,
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