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Everything posted by Alan64

  1. I got this one off of eBay... The Orion is no different really, only the labelling. The Svbony has a triplet-lens, and for a smaller and tighter red spot, but the listing should indicate that before considering it for purchase. However, mine was off its collimation a bit, and I have read of the Orion units being off, too, upon delivery to their end-users. I made a jig to collimate my own... The process explained, although I realise that you may have either collimated your own, or it was not off when you received it... https://www.youtube.com/watch?v=bE09_X43UUQ With the entry-level laser-collimators, including the Orion, the collimation should be checked upon arrival, and adjusted if off, and before using it to collimate the telescope, else the telescope's collimation may be thrown off. In addition, there are certain aspects of collimation that require passive tools instead, and that a laser cannot perform; with a Cheshire, for example... https://www.teleskop-express.de/shop/product_info.php/info/p166_TS-Optics-Cheshire-Collimating-Eyepiece-1-25--for-Newtonians---Refractors.html The Orion "Dobsonians" and Newtonians generally come with a collimation-cap, which I've found particularly useful... https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html With the cap, or Cheshire, the entire optical-system may be seen... ...and that scene from my Orion "StarBlast 6" upon its delivery, and well collimated. The factory, however, torqued down the secondary set-screws, and to where I had a very difficult time removing them. I replaced them with these later... Another enhancement, which makes collimating all the more easier, is the addition of a nylon washer, indicated there by a yellow arrow. Such keeps the tips of either the set-screws or the socket-head bolts from digging into the soft metal of the secondary-mirror's mounting-stalk. It also prevents the tips from slipping into the holes previously dug out at the factory. But that would require disassembling the secondary assembly, and ill-advised for those first starting out. An exacting collimation is only required when observing at the high and the "stupid high" powers, and for sharp and pleasing images.
  2. I would order from where it would be the easiest and the most economical for you, whether from Germany or the UK, or closer to you even. Given that your light-pollution is not that bad, you can go with a manual mount, which will save you money for concentrating on a better or larger telescope, and a few extra eyepieces and a barlow perhaps. If you don't mind learning how to collimate a Newtonian, you can choose a 150mm or 200mm "Dobsonian", or a 130mm or 150mm Newtonian on a manual, tripod-type alt-azimuth or equatorial. Spend several days, if not longer, researching the different types of telescopes and eyepieces, and before you take the plunge. After all, it's a very important purchase, especially given the amount you intend to spend. Once you find the kit of your dreams, look around for the best price, including the shipment.
  3. What's the light-pollution like at night where you live? A go-to mount benefits those who can't see a good number of stars in the sky at night, with their eyes. If the light-pollution isn't too bad, you might consider this, if you'd prefer a refractor... https://www.teleskop-express.de/shop/product_info.php/info/p2683_Skywatcher-Evostar-102-on-EQ3---Refractor-telescope-102-1000mm.html ...and if you don't mind using an equatorial mount. The mount can be motorised, and to track an object automatically. There are also kits with that same mount, but with a 127mm Maksutov-Cassegrain. Maksutovs have been described as "refractor-like", and in the quality of the images seen, but Maksutovs have very long focal-lengths, which makes it difficult to find your way around, unless it's mounted on a go-to mount. The usual suggestion is a Newtonian on a Dobson alt-azimuth, aka a "Dobsonian". You would get the most aperture for the price paid, but you would need to learn to collimate the telescope on occasion... https://www.teleskop-express.de/shop/product_info.php/info/p39_GSO-Dobsonian-Telescope-200C---8-inch-aperture-with-fine-Crayford-focuser.html https://www.teleskop-express.de/shop/product_info.php/info/p1191_GSO-8-inch-f-6-Dobsonian-Telescope-Deluxe-Version.html
  4. This is a "Bird-Jones"... https://celestron.uk.com/productinfo.php/telescopes/astromaster_series_firstscopes/astromaster_114_eq_short/3554 ...and this is a "Bird Jones"... https://www.amazon.co.uk/Meade-Instruments-Polaris-Reflector-Telescope/dp/B00LU1DAWI ...and to be avoided by those first starting out.
  5. Being mass-produced, there are going to be quite a few duds, in regard to the quality of the figuring of the mirrors and lenses, at that price-point. It's a gamble, which is why I'll be looking for just an OTA, and at a price I can live with. Incidentally, I have read of a few amateurs who have realised decent performance out of one, therefore I want to see how I might fare, but it's going to require a bit of DIY. It's an economical alternative to a Schmidt-Cassegrain, which may be part of the draw to it by those first starting out, albeit unwittingly, but its obvious attractions are its compact size and low price...and much to our dismay.
  6. That one, in yellow, is reminding of a Takahashi astrograph; perhaps it is in fact. Oh, I've seen that TS "Bird Jones" before, and waxed poetic over the prospect of actually owning it.
  7. Slowly but surely... ...the arms for the spreader are coming into being. I have one almost assembled, and once all three are completed they will be trimmed and sanded.
  8. I want a "Bird Jones", with which to putter and tinker, as I'm not a beginner; and I will have one eventually, either the Meade or Celestron. However, those first starting out would be ill-advised in the getting of one; run away, and as far as you might.
  9. The vast majority of my telescopes are small. I could conceivably display them on shelves, within a bookcase, or on a wall even. I have refractors mostly, but I like my Newtonians, too, and not necessarily for their larger apertures. Indeed, my 114mm f/8 Newtonian is a very good simulation of my 102mm f/8 refractor... There is that economical aspect of a barlow. With a barlow and 3 to 4 eyepieces: 6 to 8 differing magnifications. Although, I rarely ever, if at all, barlow an eyepiece longer than a 12mm. With the longer, a 16mm, 20mm, or 32mm, they stand on their own. Then, I do prefer the keep the number of glass elements down whenever possible, despite modern coatings. Hence, a barlow might be employed with discretion; sparingly. Congratulations upon the decision of a refractor, even if it were a common achromat.
  10. That refractor looks to be an excellent value. In choosing eyepieces, the focal-length, 714mm, is useful for planning. For your lowest power, to complement the finder in finding objects to observe, for a cruise through the star-studded fields of the Milky Way, and ample views of the galaxy in Andromeda and the Pleiades, either a 2" 32mm 70° or 38mm would serve nicely... https://www.firstlightoptics.com/ovl-eyepieces/panaview-2-eyepieces.html 714mm ÷ 32mm = 22x 714mm ÷ 38mm = 19x I'd choose the 32mm, given the very slight difference in powers. The background of the sky would be darker with the 32mm. It's also considerably smaller in size, yet sizable in its own right. You'll need a diagonal. Make it a star-prism... https://www.teleskop-express.de/shop/product_info.php/info/p9290_APM-2--Star-Diagonal-Prism-with-fast-lock-and-ultra-broadband-coating.html The BST "Starguider" series is quite popular, and would perform to your liking. You do want wider-angled eyepieces with a manual mount. You might also consider barlows, a 2x, and a 3x... https://www.rothervalleyoptics.co.uk/antares-x2-achromat-fmc-barlow-lens-125.html https://www.rothervalleyoptics.co.uk/antares-x3-achromat-fmc-barlow-lens-125.html I have both of those myself, and they have performed wonderfully with my telescopes, including my 4" f/8 refractor. If you'd to bypass the use of barlows, you can get the shorter focal-lengths with larger eye-lenses through which to observe and improved eye-relief. A 4" refractor is not too small, nor too large; a "sweet spot". A 4" refractor is the largest of the small-refractor range which begins at 50mm(2") to 60mm(2.4").
  11. Binoculars do offer just that, a binocular view, but at a static, unchanging magnification. I'd go with a short focal-length telescope, and some of the eyepieces used with the Maksutov can be used for the other.
  12. There will come a time when you'll be tempted to ramp up the power, but all of your little "ducks" will need to be lined up in a row, and to ensure sharp and pleasing images. For one, the collimation must be accurate, as precise as possible. A Newtonian cannot be collimated to a 100% accuracy, but you can get very close, and the alignment must be adjusted on occasion as the telescope is used, and moved about when travelling. Sharp and pleasing images are also dependent upon the atmospheric conditions. The quality of the telescope's mirrors, the eyepieces, and optical accessories also play a part in that. In addition, the drawtube of the focusser must rack in and out straight and true, along its entire length. If it does not, there is a reliable and enduring fix for that, one that I developed, and due to my own experiences with my kits. At the lower powers, the collimation needs only to be "good enough". At the higher powers, you will see a smaller portion of the sky, highly magnified. As a result, the object of interest will want to zip out of sight, requiring you to manually track it by bumping and nudging the telescope, and often. To extend the time, and to see more of the sky, that's where wide-angle eyepieces come into play. That's also where barlows are advantageous. For example, here is a 12mm wide-angle eyepiece... https://agenaastro.com/agena-1-25-dual-ed-eyepiece-12mm.html ...and for a power of 54x. When combined with a 2x barlow, you then have a simulated wide-angle 6mm(108x). You can use that combination for awhile. Later, you can get a 3x barlow, combining that with the 12mm, and for a wide-angle 4mm(163x). Barlows should be of the same quality as the eyepieces with which they're used. I would suggest these... 2x... http://www.scopestuff.com/ss_eba4.htm 3x... http://www.scopestuff.com/ss_eba3.htm I have both of those myself, and they've performed wonderfully with my telescopes, including a 6" f/5 Newtonian. 163x is about as high as practical with your kit, at first. The Earth's atmosphere, through which we observe, is also magnified as you go up in power, and along with its. at times, soup-like nature. Per the 50x-per-inch "maxim", a 5" aperture can realise 250x at times, particularly on the Moon which is so very near to the Earth. Indeed, the Moon can take a lot of magnification. 150x or so is considered the minimum at which to enjoy the planets. There are also "planetary" eyepieces, and with somewhat wider views over Plossls... https://agenaastro.com/eyepieces/1-25-eyepieces/shopby/bst.html Those eyepieces have barlowing lens elements built in, and with no need to combine them with a dedicated barlow. They also have nice, large eye-lenses through which to observe. To find the power of each, you simple divide 650mm, the focal-length of your telescope, by the focal-length of the eyepiece... 650mm ÷ 2.5mm = 260x... https://agenaastro.com/bst-1-25-uwa-planetary-eyepiece-2-5mm.html Now, I'm not suggesting that you run out and purchase that particular one. It is only to let you know what's out there on the market. There are more eyepieces out there than you can shake a stick at, at different levels of quality, lens-polishing, and prices.
  13. I tape a sandwich bag, with blue painter's tape, to the inside of the tube over the area to be drilled, and to catch the debris.
  14. At f/6, your telescope may make use of less expensive eyepieces, like this wide-angle 2" 32mm(38x) or 2" 38mm(32x), for your lowest power and largest view of the sky; to get your bearings, to aid in the hunt in tandem with the finder... https://www.firstlightoptics.com/ovl-eyepieces/panaview-2-eyepieces.html ...to cruise the star-studded fields of the Milky Way, to observe a good portion of the galaxy in Andromeda, and the Pleiades. As you go up in power, with a manual mount, wider angled eyepieces would be more comfortable to use. They would allow you to observe the object of interest for a longer period before having to nudge the telescope to keep track. Next up, a wide-angle 20mm(60x) or 15mm(80x), or in between the two; for the even higher powers, the collimation, the alignment of the two mirrors inside in relation to the focusser, must be more accurate. Eyepieces under 12mm or so tend to have small and smaller eye-lens through which to look. A wide-angle 12mm(100x) combined with a 2x barlow(200x) would make for a more comfortable experience. There are also eyepieces in the 4mm to 9mm range, and shorter even, known as "planetaries", that have barlowing lens elements built in, and with somewhat wider fields-of-view over standard Plossls.
  15. It is quite easy to break down a telescope. But it is a good practice to document the process with photographs, and notes perhaps, to reference when reassembling, and just as I did when I disassembled my 150mm f/5 Newtonian... Now, many of those images within that also detailed numerous enhancements and improvements that I undertook. "Up there" is so very far away, save the Moon, as it's easily seen, although it is still small. Only a telescope will reveal other, more, than the bright and dim dots and patches seen with the naked eye. This is all there is within a Newtonian... ...consisting of the focusser, the two mirrors within their retaining hardware; and all off and out of the tube. Here is the most mechanical aspect of a Newtonian: the secondary-mirror and its assembly, assembled, and disassembled... ...very few parts actually. There are two ways of mounting a secondary mirror(and its base to which it's attached): by the hub and its spider-vanes seen there, but also via a rod or stalk, and like your own... That mirror is positioned there as the focusser and the primary-mirror would "see" it, but it's oval in shape as well. That secondary-assembly is from my 114mm f/8... A Cheshire or collimation-cap would make it much easier to collimate. This is actually how you would view the scene of your own, with its stalk instead of the spider-vanes as I had shown previously; although no difference really, at all... It's all there within that image... 1. The primary-mirror, all of the white area seen; you can see its three retaining-clips, too. 2. The secondary-mirror, actually its shadow, black, there in the centre, and in the centre of that, the reflective underside of the collimation-cap(or Cheshire), and in the centre of that, the centre-spot of the primary-mirror, and in the centre of that the very small hole of the cap or Cheshire, and through which that image was taken with a camera. Dare I suggest that you might toss that laser into the bin, or at least set it aside? I've always viewed them as gimmicky, certainly the inexpensive units.
  16. Did you receive the kit new, or used? The last thing we want is for you to become discouraged and disheartened. Hmm, the first thing is to understand the nature of the beast... This is what a Newtonian, what you have, looks like on the inside, and when the light from an object in the sky travels through it, and to your eyepiece and eye... It's a clever, albeit wonky, design. It's also 100% apochromatic, which means that you can observe the brightest objects in the night, Sirius and Venus, and not see the least little bit of false-colour; red, violet and yellow edges and rings around the brighter objects; unnatural colors. Within that image, the incoming light enters the tube and strikes the larger mirror, the primary, the parabola, at the bottom. Due to the exotic curve on the surface of that mirror, the light forms a cone, and with a tip. The goal is to get that tip to the eyepiece and the eye. The small mirror, the secondary, near the front diverts the tip of that cone at the point seen, and aims it at the eyepiece located at the side of the telescope. A secondary mirror can move in every conceivable direction, but it must come to rest, locked into place, in only one position. Indeed, it is the secondary-mirror and its assembly that gives folks the most fits, as it's the most mechanical portion of the telescope. The secondary-mirror is oval in shape... ...however it's tilted at a 45° angle, and as a result it appears as near to a perfect circle, as you see it through the focusser tube, and also as the primary-mirror "sees" it... You need a collimation-cap... https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html With it, you can see the entire optical system inside... That's what your own should look like, if it's well collimated. Here's another collimation guide... https://garyseronik.com/a-beginners-guide-to-collimation/ We'll be looking forward to your success.
  17. When I first saw the AWB "OneSky", which is identical to the "Heritage" 130P, I thought "travelling", and also, of all things, the flower-children of the 1960s in the U.S.; hippies. So yes, it would lend itself well for travelling. Practically every telescope you would encounter nowadays use 1.25" eyepieces. The size is still the standard, and with the advent of 2", and even 3", eyepieces.
  18. You can mark the mirror yourself... You need a drawing-compass w/pencil, clear double-sided tape, white paper, scissors, a ruler, a permanent marker, and a single polyvinyl(plastic, not paper) notebook-paper reinforcement... Measure the diameter of the mirror with a ruler, and at its widest point. Take care not to touch the mirror's surface with the ruler, or any other object; only the paper may come in contact with the mirror. Make a paper pattern using the compass, and slightly smaller than the mirror. You want to see only a sliver of the mirror, the outside edge all around, when you place the pattern on to the mirror. That will aid you in centering the pattern over the mirror... Eye the edge over all round, and center it. Here, the paper pattern in centered on to the mirror... Take the permanent marker and press its tip into the hole made by the compass. The smaller the mark, the better. Here, the pattern has been removed, leaving only the mark made by the marker... Take the pattern and cut out a hole in the center. It doesn't have to be precise. Lay a strip of the clear, double-sided tape over the pattern's hole. Peel off a polyvinyl reinforcement from the pack, and stick the reinforcement to the underside of the tape, with the adhesive side of the reinforcement facing downward. Place the pattern back on to the mirror, center the reinforcement over the marker's mark, as shown, then press the reinforcement firmly into place... Carefully(!) lift the pattern off of the mirror and the reinforcement, and you're done... What, easier said, or shown, than done... https://www.youtube.com/watch?v=QWlB2rD-sPY
  19. What used, as the kit on hand is only £18 less than a brand-spanking new "Heritage" 130P... ...hint hint. Still, the 130P comes with the same modified-achromatic oculars, therefore the getting of the Plossls and a barlow is utterly independent of either kit, floating and hovering above them both, there in the aether.
  20. A 32mm Plossl should stand alone, given its own physical length. You'd have quite the tower jutting out of the focusser when combining a 32mm with a barlow... ...and I have no idea how far outward the combination would need to be racked to reach focus. There on the right it's racked out about halfway; a "skyscraper" even, what? That's the focusser of this Meade 114mm f/8 Newtonian that I have... ...and the configuration similar to your own. Here, I have a 20mm Erfle combined... Better, but I rarely if ever barlow an eyepiece longer than 12mm. However, for the economical aspect of a barlow, you can certainly combine a 20mm Plossl with one, and at a more practical limit. You want to keep the combinations as short as possible, especially with a 76mm telescope. I also have this "AstroMaster" 70mm long-focus refractor kit, and the refractive equivalent of your own... I'd suggest a 32mm, a 20mm, a 12mm, all Plossls, and a 2x barlow. In future, you can add a 9mm Plossl, or of another design, perhaps a wide-angle, then barlow that for a simulated 4.5mm(156x), when you're ready. You might not use a power that high very often, but telescopes in the first place are for seeing faraway objects up close, and that would be about as close to practicality as you might realise with that kit. The Moon, being so near to the Earth, takes a lot of magnification, so feel free to ramp up the power on it, maxing out the available aperture. I've barlowed a 6mm before, for a simulated 3mm, and where "Wow!" and "Look at that!" exist. You'll never know what you might see until you try. Incidentally, with that wee 70mm refractor up there, I had it up to 225x on Polaris, albeit dank and dim, yet its first-diffraction ring was sharp to the point where it appeared as illuminated teeth of a whirling circular-saw blade. Granted, that was after I had overhauled the telescope, fixing this and fixing that. Now, you and I, both, have a Celestron "Deluxe" CG-2(EQ-1) equatorial mount. It's a bit zippier, in appearance, than a dead-common CG-2 as found within the "PowerSeeker" series. As shown above, I have one too, but I haven't tried one of these on it quite yet... https://www.firstlightoptics.com/sky-watcher-mount-accessories/ra-economy-motor-drive-for-eq1.html You shouldn't have to get the more costly "Celestron"-branded one, but here it is... https://www.harrisontelescopes.co.uk/acatalog/celestron-astromaster-ra-drive-motor.html#tab-4 Here's my own Celestron drive... The Celestron drive comes with two mounting brackets, one for the CG-2(EQ-1) like our own, and one for the CG-3(EQ-2). With either 9V-battery motor-drive, you can track the objects you're observing, particularly at the higher powers where it's most needed, automatically and hands-free. You can adjust the speed of the motor even, centering an object within an eyepiece to where it stands perfectly still, and for as long as you'd like. You'll want to use a lithium-type 9V-battery for best performance, especially during the winter. Now, it would be a basic, mechanical joining, the drive to the mount, and not the most precise of integrations. You'd have to work with it to get it running smoothly, tinkering and puttering with it, but it's not that difficult really. But before ever attaching it however, you must be able to turn the worm-shaft of the RA, or right-ascension, axis with your fingers somewhat easily, and without a telescope or counterweight(s) attached. It is one of two critical areas of the mount where it may need your attention, and just as my own did in fact... This is where you adjust the tension of the worm's shaft, and to enable it to turn more easily... You must first loosen the set-screw, arrowed in green, with a 2mm hex-key I believe, but don't back it out to where it falls out, as it's quite tiny. Then, you turn the tensioning-nut either inward or outward to adjust, arrowed in yellow. Now, that nut is made of aluminum, and it can be damaged if you're not careful. I used a pair of needle-nosed pliers to turn and adjust it. There are two slots on the nut where you would insert the tips of the pliers. You might lubricate where the nut is inserted into the block, if it's too tight, and with a dab of machine-oil or WD-40. Once everything is adjusted, and to where you can twist the shaft with your fingers, with no binding of the worm or gear whatsoever, you then tighten down the set-screw, but do not torque it down. The RA-worm must also engage the teeth of the RA-gear evenly and squarely; not too tightly, nor too loosely. That can make the worm-shaft hard to turn as well. Here, you can see where the worm meshes with the gear... That meshing-together is adjusted by the bolts under the worm-block... You want the worm square and true to the gear. The other critical area is at the rear of the RA-axis, the end of the RA-shaft and its lock-nut... There is a thin, grey, textured, plastic cover that must be removed for access to the lock-nut. The lock-nut may then be adjusted, either with a socket-wrench if one will fit into the cavity, or with a heavy-duty pair of needle-nosed pliers... You want the RA-axis to spin around freely and smoothly, and without slop. A less critical and much easier adjustment is to the DEC, or declination, axis, and to its lock-nut. The nut lies just under where the telescope is mounted and clamped. It does not have a cover... In the end, you want both axes to rotate freely and smoothly, with no binding, no slop, and like a well-oiled gyroscope... https://www.youtube.com/watch?v=p9zhP9Bnx-k Do not think for one moment that these mounts leave the factory well-adjusted, for they do not, and as my own had revealed. Once put in order, there will be little to no risk of damaging the mount or a motor-drive, or whether when using the manual, slow-motion controls that come with the kit. Lastly, very few amateurs take these mounts seriously, but I do. Many will say that it's "flimsy", "wonky", or belittle it in other ways. The CG-2(EQ-1) is the smallest of equatorials, yet it is fully functional and usable, and best suited for a camera or a rather small telescope. I have two or three such telescopes that will be mounted upon it, and after I disassemble and overhaul it.
  21. Hi Harvey, Your 76mm Newtonian has a 700mm focal-length. For your lowest power, a 32mm Plossl will help you find your way around the sky, along with your red-dot finder... 700mm ÷ 32mm = 22x, and almost binocular-like, power-wise. I would get one of those straight away... https://www.365astronomy.com/32mm-GSO-Plossl-Eyepiece.html The nice thing about getting eyepieces is that you will always have them, as long as you don't lose or break them. Breaking one is actually extremely difficult to do. They will be there for telescope after telescope after telescope in future. The 20mm that came with your kit is an erecting eyepiece, and suitable only for daytime/terrestrial use; birds in trees, ships at sea, and other various and sundry land-targets during the day. You can get a 20mm Plossl(35x) for use at night... https://www.365astronomy.com/20mm-GSO-Plossl-Eyepiece.html Now, a 10mm eyepiece comes with your kit, but you might like a wider and improved view. You can barlow the 20mm Plossl, and for a simulated 10mm(70x), with a 2x barlow... https://www.365astronomy.com/GSO-2x-Barlow-2-Element-Achromatic-Barlow.html For the higher powers, your telescope should be able to realise at least 125x, perhaps up to 150x if the collimation is bang-on, and for the Moon, the planets, and the double-stars. Let's see what you'd need to reach 125x first... 700mm ÷ 125x = a 5.6mm eyepiece; well, that's an odd size. You can get a 12mm Plossl(58x) from that same listing, combine it with the 2x barlow, and for a simulated 6mm(117x). Now, let's see what 150x would require... 700mm ÷ 150x = a 4.7mm eyepiece; hmm, there's another odd size. Let's round that off a bit. With the 2x barlow, you can get a 9mm Plossl(78x), and for a simulated 4.5mm(156x). With a 2x barlow, and three to four eyepieces, you can have six to eight different powers at your disposal. It's like having six to eight individual eyepieces, but without the extra cost. Eyepieces are fully one half of the telescopic experience. A telescope and a set of eyepieces are as one, and inseparable. You can't use one without the other, therefore eyepieces are just as important as the telescope. Indeed, there are quite a few experienced amateurs who have spent more on their eyepieces...than they did on their telescopes.
  22. Both kits are nice, and will perform to your expectations. The Orion XT4.5 has the same Newtonian OTA as that of my Meade kit... ...although the XT4.5 is perhaps more staircase-friendly. Both have a focal-length of 900mm. At f/8, it is a "planetary" telescope, and for the medium-to-high powers. You might find the need for a 2x barlow eventually with the XT4.5. The primary-mirror, at the bottom of the tube, is a lesser spherical, but a spherical performs quite well at f/8, as my own does. The Zhumell Z130, with a 650mm focal-length, at f/5, is also a Newtonian, and intended as a low-to-medium power telescope; however higher magnifications are certainly possible, via its superior parabolic primary-mirror, and with a 2x barlow definitely required, if not a 3x. The barlows will, in effect, extend the focal-length of the Z130. I have a 150mm f/5 Newtonian... ...but you wouldn't want to haul that one up and down a flight of stairs. I've regularly used a 3x barlow with it, as its focal-length is only 750mm. The Z130 would be the more versatile of the two, for magnifications ranging from a binocular-like 20x, to 150x and beyond with, again, 2x and 3x barlows. A 32mm Plossl inserted, at 20x, would show you a larger part of the sky, to aid in the hunting of objects. Once an of object of interest is found, you then begin switching out eyepieces and ramping up the power for a closer look. This illustrates the field-of-view when observing the Moon through the XT4.5(red) and the Z130(yellow), and with a 32mm Plossl at 20x inserted into both... As shown, you can see a larger part of the sky at that lowest power with the Z130. With longer-focus telescopes, owners of those oft lament that they cannot realise low-power wide-field views. With the Z130, you can have your cake and eat it too.
  23. Yes, that's the long-focus Newtonian, a true Newtonian, and the same 114mm f/8 OTA as I have within this Meade kit... The OP's OTA however, whilst of the "PowerSeeker" series, is, as evident by now, quite different. Incidentally, Meade did one better with that kit, as they included a sturdier EQ2-class mount.
  24. Hello, I'm afraid you won't get much use out of the 20mm. The field-of-view will be quite narrow when compared to a 20mm Plossl. Entry-level kits do not include the best of eyepieces and accessories, so you'll want to complement the experience with a Plossl or two, or three. The included 10mm is most certainly usable, but it's not a Plossl, either. Plossls are the barest minimum if you're wanting performance, and they're not expensive... https://www.365astronomy.com/GSO-Super-Plossl-Eyepieces/ I would suggest a 32mm from that listing, and to help find your way around the sky. That will serve as your lowest power(20x), for hunting, for observing the star-studded fields of the Milky Way, the Pleiades, and the galaxy in Andromeda. A 20mm Plossl will give you a power of 33x, and for closer look. You can barlow the 20mm Plossl, for a simulated 10mm, with a 2x barlow... https://www.365astronomy.com/GSO-2x-Barlow-2-Element-Achromatic-Barlow.html ...and for a power of 65x. A 130mm aperture is capable of reaching even higher powers, however the manufacturer equipped that model with a spherical primary-mirror, instead of the accepted and expected parabolic. A parabolic primary-mirror is the standard for f/5 Newtonians. Why they chose to do that is somewhat unknown. Therefore, it will be more difficult to reach, say, 150x, whilst at the same time enjoying sharp and pleasing views. But you can certainly attempt 150x, and where the planets and other objects come into their own; for a closer look at the craters of the Moon, and for the splitting of double-stars. The focal-length of a 130mm f/5 is rather short, at 650mm. Let's see what it would take to reach 150x, when the time comes... 650mm ÷ 150x = roughly a 4mm eyepiece In that event, you would need a 12mm Plossl and a 3x barlow, and for a simulated 4mm(163x)... https://www.rothervalleyoptics.co.uk/antares-x3-achromat-fmc-barlow-lens-125.html Or, if you already have a 2x barlow at the time, you can get either an 8mm or 9mm eyepiece. With the 2x barlow and the 8mm, you would have a simulated 4mm(163x); with the 9mm, a simulated 4.5mm(144x). Those are merely examples and suggestions. Eyepieces are fully the other half of a telescope. The two are one and inseparable. You can't use one without the other, unless a camera takes the place of an eyepiece, as when imaging with a telescope. The eyepieces and other accessories do not have to be acquired all at once, and they should be chosen carefully, as the eyes from individual to individual differ. For example, if you wear prescription-eyeglasses, and find that you need to wear them at the eyepiece, then you may need eyepieces with longer eye-relief, and in order to see the full field-of-view. Eye-relief is noted within the specs of the listings of most eyepieces; usually, 20mm of eye-relief is preferred by eyeglass-wearers. Eyepieces, barlows and other accessories only have to be acquired once, as long as they're not lost or broken, and they can be used with any other telescope(s) that may be acquired in future. I have over twelve telescopes, but only one of each focal-length of eyepiece, mostly. You can motorise the RA-axis of the kit's mount, and with an economical 9V-battery(a lithium-type during the winter) motor-drive... https://www.firstlightoptics.com/celestron-astromaster-series/motor-drive-celestron-astromaster-geq-93514.html Such will allow you to track an object automatically, hands-free. It will even cause an object to stand still there in the center of an eyepiece, and for as long as you'd like.
  25. Just a test-fitting... They're attached to the tripod-hub of the Meade "Large Equatorial" EQ-2, which is about 4.25" in diameter. The hub of my Astro-Tech Voyager I is 4.5" in diameter. That of the Celestron CG-4(EQ-3) is less than 4" in diameter. If, in future, I attach these legs to the hub of an EQ5-class mount, would it be of the same diameter as that of the CG-4? Curiouser and curiouser... Once the proper length of the spreader's arms are determined, they will be crafted, and then all of the components will be stained and spar-urethaned. I may need to work out a solution for cushioning the corners of the tips of those yokes when folding up the legs.
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