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Everything posted by Alan64

  1. You had asked the same within a PM. I've replied to you there.
  2. Agena Astro, in California, offers a collimation-cap, and with every item they sell with free shipping... https://agenaastro.com/rigel-systems-aline-telescope-alignment-eyepiece.html The collapsible's tube would need to be sealed, with a shroud I imagine, then a white cloth or other over the opening at the front. Then, a lamp in front of that to illuminate the telescope's interior... It is then that the entire optical system can be seen, although I use a small camera to zoom in and snap a shot. It's all there within this image, and with the collimation thrown out slightly to illustrate and describe... 1. The hole in the center of the cap, and through which the image was taken with a camera 2. The center-spot of the primary-mirror 3. The reflective underside of the cap 4. The silhouette, or shadow, of the secondary-mirror 5. The secondary-assembly's spider-vanes; nasty things those are. 6. The reflective surface of the primary-mirror; all of the white area in fact 7. The primary-mirror's clips; all three, or however many, should be visible, and evenly. 8. The interior of the drawtube
  3. There's nothing like receiving a package from the UK, like that time I had sent a sample of questionable tea to Twinings, its having been packed here in the States, whereupon they discovered that it had indeed been adulterated. They then, much to my surprise, sent me a box of several different flavoured teas of theirs that were absolutely wonderful, whilst they lasted. I don't think I'll ever receive anything that nice again... https://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html That's the best Cheshire in the world, at present, although not due to its anodised colour; but that does make it a bit special nonetheless. You won't misplace it. If you want to give another one of these a try, there's something you should know about them... They're improved now, and with a triplet-lens, for a tighter dot... https://www.ebay.com/itm/1-25-SVBONY-7-Bright-Level-Next-Generation-Laser-Collimator-for-Astro-Telescope/263812604382?hash=item3d6c74e1de:g:zHsAAOSw3vFbWh6T:rk:2:pf:0 But, as with all entry-level laser-collimators, it will most likely require collimation, and before it's used to collimate the telescope... https://www.youtube.com/watch?v=5ZsgNlgIrqQ When you have trouble with slop, with a telescope's visual-back, you shim it. For example, I have this focusser, but it's not a 1.25", a 1.26" instead... That's a shim of .005"-thick PVC... https://www.ebay.com/itm/Midwest-Products-70406-Blue-PVC-Sheets-005-x-7-6-x-11-4-sheets-/183636053625?_trksid=p2385738.m4383.l4275.c10#shpCntId#shId https://www.hobbylobby.com/Crafts-Hobbies/Hobbies-Collecting/Tools-Blades/Brass-Sheet---0.005"/p/21620 You get the idea. If in a pinch, a layer or two of clear packing tape will serve. However, you may need a shim that's thicker, I do not know. In that event, and if you don't have one already, get one of these calipers. I have one myself, and I wouldn't be without it when working with my telescopes... https://www.harborfreight.com/6-in-digital-caliper-61585.html That would enable you to determine the exact deviation from the norm, then to shim accordingly.
  4. The components have now been stained, although not yet sealed... I can't wait to see them after they're urethaned.
  5. The hunting of comets requires a wide field-of-view, the widest possible, and at the lower if not the lowest of powers. An f/5 refractor is ideal for that very thing. Somewhat recently, I had my 80mm f/6 out observing Comet Wirtenan... Over the course of time, fifteen to thirty minutes, I was able to notice the comet's movement in relation to other objects nearby, and quite close to the comet those were, thereby making the detection that much easier. All in all, not a bad show, not at all. A 200mm f/2.4 achromat would've been far better, of course, if such were possible; ever hopeful I am in that fantasy. The f/5 achromat in question, an "ST80" I believe, comes with a 1.25" focusser. A 32mm Plossl would provide the lowest power(12.5x) and the widest view practical. 80mm f/5 achromats are routinely re-fitted by amateurs with 2" focussers, for this purpose and that. This one from China appears to be viable, and with a 78mm threaded interface; naturally, a bit of DIY work is to be expected in its integration... https://www.ebay.com/itm/New-2-Manual-Gear-Focusing-Focuser-for-Refraction-Astronomy-Telescope/323419115167?hash=item4b4d480e9f:g:PwsAAMXQDK1RtT2P:rk:27:pf:0&shqty=1#shId I changed the country to "United Kingdom", then selected "Get Rates": £54, and with free shipping. However, it would be for the user to decide if the effort would be worth the while. To wit, a view of the Moon with an 80mm f/5 achromat, a 1.25" 32mm 52° Plossl, and a 2" 32mm 70­° wide-angle ocular... https://goo.gl/fCQkdG Then, if the views through the achromat have been beyond satisfactory, that is, if the achromatic doublet is of an above-average figurement and polish, then it would most certainly be worth the while to upgrade it. If the level of quality of the doublet is presently unknown, get the power up to 150x or greater, aim it at the Trapezium within Orion, for one, and note the thinness of the first-diffraction rings of the brightest stars. You want them as razor-sharp as possible, and the atmospheric seeing is to be at least good, or better. If said upgrade is not possible or practical, a 32mm Plossl does, after all, offer a reasonably wide field-of-view. Although, I would not suggest spending a lot on a 1.25" mirrored star-diagonal, if you're going to stick with the 1.25" focusser. You may, however, want better, a dielectric, and for the specialised purpose at hand.
  6. All of the components received their final sanding with 150-grit paper, and then wiped down with 91% rubbing-alcohol... Staining and sealing during the winter is not the easiest thing to accomplish, but done it must be. The only place where I can get it done, is within that smallest of rooms within a home, and with the ventilation-fan running.
  7. Most people when using or hearing of the term "catadioptric" do indeed think of the second definition: Schmidt- and Maksutov-Cassegrains, therefore a refractor, with or without a mirrored diagonal, is most certainly not either one of those. Although, the Maksutov-Cassegrain has been described as being "refractor-like", and is the only reflecting telescope so considered. A Maksutov is also the only modified-Cassegrain that I would own and operate. I would also like to have a classical Cassegrain.
  8. A catadioptric is any telescope where refraction and reflection are combined; lenses and mirrors, whether a modified-Cassegrain(Schmidt and Maksutov), or a refractor with a mirrored diagonal. If you must use a diagonal with a refractor, always endeavour to make that one a prism; to preserve the "feng shui". A mirrored diagonal is suggested, however, for f/5 achromats. In addition, combining a mirrored diagonal with a Schmidt- or Maksutov-Cassegrain is, in effect, adding a third mirror to the light-path, which may only serve to increase the incidence of light-scattering.
  9. People use diagonals regardless if they are good or bad because it's far more ergonomic. Straight-through observing is a lost practice for the vast majority, save for the Japanese(at last count). The secondary-mirror of a Newtonian is that telescope's "diagonal". Have a look at this "refractor"... https://explorescientificusa.com/products/products-package-deal-bresser-comet-edition-102mm-refractor-kit-variant-2221347844 That is a catadioptric. In so far as a diagonal not degrading an image, think again. The more you add to the light-path, the greater the chance for degradations; light-scattering in the case of a mirrored diagonal. Then, there's the miscollimation of either a mirror or prism with which to contend. When one does place a diagonal into a refractor, you still can't use the telescope until you add an eyepiece, therefore the diagonal, when integrated, becomes one with the refractor, a component of the telescope's light path, and just as the secondary-mirror of a Newtonian; therefore, again, a catadioptric when using a mirrored diagonal. I suppose, rather, that you might hold that a Newtonian becomes a catadioptric when an eyepiece is inserted; most definitely not a refractor by any stretch of the imagination; however your point is moot, as eyepieces are not an integral part of a telescope's light-path, rather the receivers of the light-path instead. Observe what happens when the tip of the light-cone of an objective nears an eyepiece... Note where the tip of the light-cone ends, and just as it exits the body of the diagonal. Eyepieces are, again, merely receivers, and therefore cannot transform any telescope into another. This is my 80mm f/6 achromat, but with a 2" mirrored diagonal. Configured so, it is in a catadioptric mode of operation... If I take the mirrored diagonal out, and put a prism diagonal in its place, the telescope then reverts back to being a refractor; closer in any event, as some regard the "total internal reflection" of a prism diagonal as just that, a reflection. However, there is no light-scattering, aluminised coating involved. In a straight-through configuration, without a diagonal at all, the refractor is at its very best, in form, function, and performance. Incidentally, in the case of a barlow, if inserted before the diagonal it becomes a part of the telescope's light-path. If the barlow is inserted after the diagonal, it becomes a part of the receiver, the eyepiece. 2" mirrored diagonals are more popular not because they're so very wonderful, but simply because they're cheaper to make, and purchase. I do not look upon mirrors as a cure-all, and as so very many others do.
  10. The brass tubing, the bearings, were roughly sanded... ...then epoxied into the arms... All of the wooden components will now receive their final sanding, then the staining and sealing.
  11. Indeed, the addition of a diagonal of any sort can never be an improvement, observationally; only in an ergonomic sense. However, the use of diagonals has become so commonplace that their omission is practically unthinkable for the vast majority of amateurs; and that is regrettable, particularly when combining a mirrored diagonal with a refractor, thereby transforming the refractor into a catadioptric.
  12. This erect-image diagonal has a 29mm aperture... https://uk.telescope.com/Orion-125-Pentaprism-Diagonal/p/130876.uts It's a five-sided prism, a pentaprism diagonal, and for correctly-oriented views. In addition, there would be no Amici-line seen when viewing brighter objects; although you would very rarely encounter that, if at all. Given its generous aperture, and per the observational agenda, that one would be best; for a correctly-oriented view. It is only a 1.25", however. For comet-hunting, I would use a 2" diagonal, and 2" oculars.
  13. For imaging in general, think small telescope, and a HUGE mount. For imaging planets and galaxies... https://www.bhphotovideo.com/c/product/644961-REG/Celestron_91030_XLT_EdgeHD_8_Optical_Tube.html https://www.telescope.com/catalog/product.jsp?productId=116277&gclid=Cj0KCQiApvbhBRDXARIsALnNoK03T34TV0BdDd3k2QLaUBBKJQUOXyVfyVRcMvjeyrGJx_59oAlsotcaAlsmEALw_wcB ...that is, an EQ6-class mount over an EQ5-class(AVX) mount.
  14. I'm a bit late to this thread, and I do hope I'm not too late; my apologies in advance. The Celestron "Astromaster" 130EQ does not come with a parabolic primary-mirror... https://www.celestron.com/blogs/knowledgebase/does-my-astromaster-130-have-a-spherical-or-parabolic-mirror-what-is-the-difference Synta, the manufacturer, went against the maxim that an f/5 Newtonian, regardless of aperture, is to have a parabolic primary. As to why is one of the great mysteries of the universe, although I know why. The telescope in question contains a spherical primary-mirror instead, which works well at f/7 and longer, but not with the shorter, at f/5. What this means is that the telescope is suitable only for the low to medium powers, if that high. Sharp and pleasing images at the higher powers, of which a 130mm aperture is certainly capable, will be elusive with the kit in question. The Sky-Watcher and Meade 130mm f/5 Newtonian/EQ-2 kits do in fact come equipped with parabolic mirrors, with the Sky-Watcher the best of the two, for sharp and pleasing images throughout the range of magnifications of which a 130mm aperture is capable, from 20x, to 150x and beyond with the aid of 2x and 3x barlows... https://www.firstlightoptics.com/reflectors/skywatcher-explorer-130p.html https://www.amazon.co.uk/Meade-Instruments-Polaris-Reflector-Telescope/dp/B00LU1DY8S Again, my apologies.
  15. When star-testing any telescope, a general rule of thumb is to use an eyepiece with a focal-length that's identical to the telescope's focal-ratio; f/6 in this instance, therefore a 6mm(200x). Although, if I star-tested my 70mm f/13 achromat, I would use a 9mm or so; for, after all, the higher in power you go the more accurate the test.
  16. It's perfectly allright to start a child out at that age, if they've previously expressed an interest in the sky, and so the child in this instance has in fact: "Mars, Mars, Mars...". As the child grows, so the interest, and with a firm foundation. I would advise the getting of a telescope kit first, learning how to use it, learning everything about it, and then to tackle the integration of a remote viewing solution. Ideally, you would need a go-to mount with a telescope attached to it, to keep the image of an object steady and on track. You would then attach a webcam to an eyepiece, the webcam connected to a laptop or other with a viewing screen. It can also be done with a manual mount, and with lots of practice in effecting the views from the eyepieces on a screen for the child. You would need an equatorial mount to track, and it can be motorised to track automatically... https://www.bhphotovideo.com/c/product/1061420-REG/meade_216006_polaris_130mm_german_equatorial.html/?ap=y&gclid=CjwKCAiA4OvhBRAjEiwAU2FoJalBuT3-ipbnmWyvpl6wRpr6s_Q0TilbSHhfZGOEWsOGnqxAUtUyARoCuIcQAvD_BwE&lsft=BI%3A514&smp=Y The motor-drive... https://www.bhphotovideo.com/c/product/1123835-REG/meade_616000_polaris_dc_motor_drive.html/?ap=y&gclid=CjwKCAiA4OvhBRAjEiwAU2FoJWzL5gHuEbIHIyjqrx_JcXxpzodkq1hlNilhn6_eiv8wFtyfmc--cBoCHhcQAvD_BwE&lsft=BI%3A514&smp=Y The drive has a speed control, for centering an object in the eyepiece and making it stand still. In winter, you would want to use a lithium-type 9V-battery. In order to motorise the mount, the RA-axis must operate freely and smoothly, with no binding throughout its motions. The mount may need to be loosened up at this point and that upon its arrival, or tightened up, whichever, and so to prevent damage to the drive. The mount comes with slow-motion controls, which will enable you to track an object by hand. For improved stability, the legs of the tripod should not be extended. I can show you how to do all of that to the mount if you choose that kit, as I have one, too, but with a longer-focus Newtonian upon it... The telescope itself would need to be checked for proper alignment, its collimation, and for sharp and pleasing images; upon arrival, and occasionally thereafter as the telescope is moved about and used. The eyepieces and barlow included with that kit are not very good, but they will serve at first. You will want to replace them with better as time goes by. If you'd rather not deal with the collimation of a Newtonian, you can choose a refractor which usually has no need to be aligned, collimated, and that type of telescope mounted on an equatorial as well... https://www.bhphotovideo.com/c/product/1291493-REG/explore_scientific_fl_ar80900eq3_firstlight_ar80mm_f_11_refractor.html The refractor of that kit would need a star-diagonal(for nighttime/celestial targets) to replace the Amici-diagonal(for daytime/terrestrial targets) that comes with the kit... https://www.bhphotovideo.com/c/product/201981-REG/Celestron_94115_A_Star_Diagonal_1_25.html Thoroughly research the following methods online, and the items themselves, before assembling a viewing solution... You will need a webcam, that's connected to a laptop, to attach to an eyepiece. Such is called eyepiece-projection... https://www.youtube.com/watch?v=2uSzBwQxRDU The author of that video states that his webcam is of a standard PC-type, rather than a more expensive astronomical type. You want a webcam with the best low-light sensitivity. But I wouldn't use tape to attach the webcam to the eyepiece. Rather, I would use velcro at a minimum; or make something with wood or plastic, screws and what-not, and for a frame-like adaptor. There is also this method when wanting to use an inexpensive webcam, and where the camera would take the place of an eyepiece. This method may require the use of a 3x or 5x barlow; or, with the eyepiece-projection method, and with the camera attached to the eyepiece instead... https://www.youtube.com/watch?v=1gF6iHrZ4Rw https://www.amazon.com/SVBONY-Filter-Adapter-Capture-Planets/dp/B06X917V27 3x barlow... https://agenaastro.com/meade-128-3x-barlow-07278.html 5x barlow... https://agenaastro.com/gso-5x-apo-barlow-lens.html (Incidentally, a 5x barlow would not really be suitable for observing with eyepieces, and with eyes directly, but that would depend upon a user's personal preference.) What a truly wonderful thing you're doing. My best wishes for your success.
  17. What you have there is a Newtonian, and invented by this polymath, in 1668... https://news.nationalgeographic.com/content/dam/news/photos/000/116/11606.ngsversion.1475440206776.adapt.1900.1.jpg If you line all of your "ducks" into a row, you will have an adept and powerful instrument with which to observe the celestial void. In addition to the mechanical repairs, the Newtonian will benefit most from a blackening and flocking; arts & crafts work. You may also need to have one or both mirrors re-coated. Do you live in California?
  18. Hello, and welcome... Your telescope is a 76mm f/4 Newtonian, and designed primarily, if not exclusively, for low-power wide-field views. There is reason to expect to reach a power of 125x, or 150x, with the telescope, but the higher in power you go, the more critical, the more accurate the collimation, the alignment of the two mirrors with the focusser/eyepiece, must be. I have the next size up from yours, a 100mm f/4 Newtonian... I got mine for one purpose, primarily: to observe the galaxy in Andromeda, as its huge, and requires very low power and a very wide filed-of-view to even hope to see it in its entirety. I resigned myself to that whatever else might be seen with it would be icing on the cake, particularly at the higher powers; miraculous even. The primary-mirror of my own was glued in place at the factory overseas; no clips, no adjustments, but no matter really... However, I couldn't use my collimation-cap. Through the cap, I saw only this... ...along with those dreadful spider-vanes. So, I set to center-spotting the primary-mirror... https://garyseronik.com/centre-dotting-your-scopes-primary-mirror/ I used a polyvinyl(plastic), not paper, reinforcement... Now I can use the collimation-cap, or a Cheshire, and to its fullest potential... As you can see, it was practically bang-on from the factory. Yours may be, too, but you won't know it until you add a spot to your mirror. The more precisely the spot is placed, the more accurate the collimation will be. Incidentally, I suspect that the primary-mirror of your telescope is also glued into its cell, and therefore may not be pinched. If so, the astigmatism that you're seeing lies either with the eyepieces that came with your kit, or with your own eyes. I do hope the former. Now, I'm not seeing any ready-made caps being offered over there in Australia. If the focusser of your telescope, the drawtube specifically, came with a dust-cap, you can make a collimation-cap out of it... You would need to drill a very small hole, as shown, precisely in the center of the cap, then line the underside, as shown, with either the dull or shiny side of a circular piece of aluminum foil. Try it with both sides, and see which is best. The telescope must be illuminated at the front opening. I place a white cloth over the opening, and then a lamp in front of that. You may also find that by using a small camera that you can zoom in on the scene and for a closer look, and just as I did within those images. If you did not receive a dust-cap, others have used the old-style 35mm plastic film canisters. I would cut the canister down to half, and line the underside of the snap-on cap with the foil. The secondary-mirror of your telescopes appears to be adjustable from what I've seen online, but the primary most likely is not, not in a conventional sense. If you ever do need to adjust the tilt of the primary-mirror, you can slot out the round mounting-holes on the tube for the mirror's cell... That would allow for enough movement to accurately tilt and adjust the primary, then to batten down the screws. That modification will be possible only if the mounting holes are not threaded for the screws. All of that, therefore, is if you desire to get the most out of the telescope. In addition, you can get improved eyepieces, not only for that telescope, but for others that you may acquire in future. The minimum in performance eyepieces are Plossls. Plossls tend to play well with the f/4 parabolas of Newtonians. A 32mm Plossl would serve as your lowest power, 9x, a binocular-like power, and would aid the finder in the finding of objects to observe. It would also enable you to see the largest part of the sky, for cruising the star-studded fields of the Milky Way for example. A 15mm Plossl would give you a power of 20x. A 12mm Plossl...25x. Those are all rather low powers. The 10mm included with your kit...30x; a bit higher, but still a low power. The planets come into their own at about 150x. Let's see what that would take. Your telescope has a focal-length of 300mm, and quite short... 300mm ÷ 150x = a 2 mm eyepiece That short of an eyepiece is quite difficult to come by. Let's try 125x instead... 300mm ÷ 125x = a 2.4mm eyepiece 300mm÷ 100x = a 3mm eyepiece 100x seems to be the most practical, in so far as eyepieces combined with barlows. You can get an 9mm eyepiece and a 3x barlow, and for a simulated 3mm(100x). You can get a 6mm eyepiece and a 3x barlow, and for a simulated 2mm(150x). You would probably want to get wide-angle eyepieces for those higher powers, as the sky grows smaller as you go up in magnification. Plossls, shorter than 9mm or so, have rather small eye-lenses and short eye-relief; uncomfortable to use. Eyepieces range, in general, from 4mm to 40mm. That range is pretty inflexible, static, unchanging. But telescopes come in many different focal-lengths, and all must conform to that unyielding range of eyepieces. For example, an ideal focal-length for matching with said range of eyepieces would be about 900mm to 1000mm, like that of this 114mm f/8 Newtonian... Although, even a 650mm(130mm f/5) or 750mm(150mm f/5) focal-length would do, and with the aid of 2x and 3x barlows.
  19. When I saw that incredible amount of detail, it was only for a brief time, then it went back a step or two down in sharpness. That was the atmosphere's doing; the "seeing". Patience is required in waiting for moments of good seeing during a night of average-to-poor seeing conditions, as we can never know when it will occur. When observing the Moon, the variable-polariser will enable you to dim it down, if it irritates your eyes, especially during a full phase. Of course, during a full Moon there's very little contrasting detail to be seen, but I look at it anyway with my telescopes... The variable-polariser can also be used to discern the phases of Venus; phases just like those of the Moon. You may come to find that Saturn does not really need to be dimmed, depending. Colour filters? Back in 2012, I went ahead and cobbled a set together, and after researching them... The dark ones are for much larger "Dobsonians", 12", 16", and up. I wanted those anyway, if only as curiosities. The lighter colours can be useful: the #80A and #82A blues. The lighter yellows can be used with fast-achromats to reduce the effects of false-colour when viewing brighter objects, although the detrimental effects(blurring, smearing) upon an image due to the chromatic aberration remain. They also impart a yellowish cast to the images. Still, I rarely, if ever, have used or will use any of those filters.
  20. Getting there... ...
  21. There's one item you might want to get straight away, and to noticeably improve the view when you use a diagonal at night: a star-diagonal. The very name for the type, "star", is self-explanatory, and denoting its use for the stars and their companions in the night sky. Your refractor came with a 45° Amici-diagonal, which is really only suitable for daytime/terrestrial targets; birds in trees, ships at sea, those sorts of observations. At night however, when observing the sky, you want a star-diagonal to see a wider, brighter view. To illustrate, I have an Amici-diagonal just like your own, the one that came with your refractor. But I also have a star-diagonal... Star-diagonals are always oriented at 90°, for when you use it at night, the telescope is being aimed higher above the horizon, quite a bit above the land and sea targets seen during the day. That 90° angle makes a star-diagonal more comfortable to use. That's one advantage with a star-diagonal. Another, more important advantage is the diameter of the diagonal's light-port... See how much larger in diameter the port is with a star-diagonal? Your refractor was designed for low-power, wide-field views, therefore you need a diagonal with a wider light-port: a star-diagonal. The recommended star-diagonal for an f/5 achromat, as your own, is a mirrored type. If you live in the UK... https://www.rothervalleyoptics.co.uk/antares-90-star-diagonal-125.html There's no image of it within that listing, but here's an image from a vendor in Canada... https://www.ontariotelescope.com/125-Diagonal_p_121.html Now, there's no obligation to heed what I say. I've been observing the sky since I was about 9 years old...over 40 years ago. Seriously, I care, and in wanting you to get the best out of your new telescope.
  22. I have a 6" f/5 Newtonian. I assume the "big light bucket" that you're wondering about is at least an 8". Jupiter is generally bright, so much so that through my 6" f/5 the planet appeared as a brilliant white, washed-out sphere, and practically devoid of any detail. I then attached one of these to my eyepiece, then the eyepiece into the barlow as before: a variable-polariser... https://agenaastro.com/gso-1-25-polarizing-filter.html NOTE: You must have two of them, then to screw them together and adjust for a brightness range from 1% to 40%, and in allow those percentages of light through to the eyepiece. Also note what is stated there in the listing, "Buy 2 for $12.50 each and save 8%". AA offers that discount, and for making a variable-polariser out of the two. This is an image of my variable-polariser, and illustrating the different levels of light passing through... Jupiter, before I went into the house to get my unit(left), and after the unit was integrated(right)... The unit also dimmed down the flaring caused by the secondary-spider vanes; eliminated them even. The view made my jaw drop. I could then see the whorls and festoons within the planet's equatorial bands, and almost sharp as a tack. I say "almost" because I was near to the magnification limit per the atmosphere, high power whilst using a 3x barlow, at the time of the observation. You'll see what I mean when you eventually point a larger aperture at Jupiter.
  23. A 200mm f/6 Newtonian on a Dobson alt-azimuth is the usual suggestion, but there are other types of telescopes. A Newtonian offers the most aperture per pound spent, but that does not come without a price of another stripe. Newtonians oft require collimation, the alignment of the optical system, at times upon their arrival to the user from the factory, and occasionally thereafter as the telescope is moved about, travelled with, and used. Look over this tutorial to see if collimating a Newtonian would be to your liking... http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/ Actually, no one really likes to collimate a telescope, but many muck on through the process, and for the extra aperture. The need for an accurate collimation increases as you go up in magnification. For the low to medium-low powers, the collimation doesn't have to be bang-on, just "good enough". In order to effectively suggest and recommend, it would be of help to let us know as to the level of light-pollution where you will be using a telescope.
  24. The ends of the arms have been rounded, but for the holes to be drilled I'll need to make a template...
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