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Alan64

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Everything posted by Alan64

  1. If you like the go-to mount-head of that kit, then you might want to do something about the legs of the tripod that supports it; or rather does not support it adequately... I'd suggest locating wooden legs for the kit... The tripod-hub, to which those wooden legs are attached, used to have the same legs as those of your own kit... Know that the manufacturers overseas are going to provide only enough to get the telescope up off of the ground. Hence, the mount-head and telescope require a tripod that's a bit more substantial. You can locate a new or used surveyor's tripod, with wooden or fibre-glass legs, however you would need to craft a spreader to tie them together. In a pinch, a spreader of chain; the chain, a center-ring and whatever else to be had at your local hardware, to keep the legs from spreading out too far. Wooden legs are the best choice; perhaps a stout pier even, albeit less mobile.
  2. A 2x-barlow serves two purposes, in so far as visual-use... 1. The economical aspect, in combining a barlow with 2 or 3 eyepieces resulting in 4 to 6 differing powers. In carefully selecting the eyepieces to combine with the barlow, the goal is to avoid duplications. For example, if you barlowed a 20mm, and for a simulated 10mm, you would not need a dedicated 10mm; and so on. You might then choose an 8mm, 12mm, or 15mm instead. 2. The ergonomic aspect, in avoiding a 4mm eyepiece for example, and with its tiny eye-lens and tight eye-relief. Instead, you would barlow an 8mm or 9mm, and with their larger eye-lenses and greater eye-relief. Now, that's when dealing with orthoscopics and Plossls. There are eyepieces that have barlowing lens-elements built in; for example... Note the generous eye-lens, and for a 4mm eyepiece. Then, compare it to this 4mm symmetrical-Ramsden... Such enhanced eyepieces also offer slightly wider fields-of-view over Plossls. Plossls are the current, minimum standard in performance-eyepieces, and they have come down in price considerably within the last several decades. "MA" stands for modified-achromat, like the ones that came with our Meade kits. Eyepieces that are less complex than Plossls, and even cheaper to produce -- modified-achromats, Huygenians, Ramsdens -- do work well with telescopes with longer focal-lengths, like our own. Since they do in fact, the manufacturers tend to include them with all entry-level telescope kits, albeit regardless of a given telescope's focal-length. In that enterprise, the rubbing of two copper coins together makes four or more. Although, that 4mm Ramsden illustrated there, from a kit, has astounded me, albeit when paired with its 127/1000 telescope. Don't hesitate to acquire quality eyepieces, barlows and other accessories for your telescope, for unlike telescopes those items can be used with other telescopes that may be had in future. They're wonderfully interchangeable; and like luggage, they are with us for a lifetime. Plossls... https://www.365astronomy.com/GSO-Super-Plossl-Eyepieces/ An example of a quality barlow, and one that I have myself... https://www.rothervalleyoptics.co.uk/antares-x2-achromat-fmc-barlow-lens-125.html Enhanced eyepieces... https://www.firstlightoptics.com/bst-starguider-eyepieces.html Of those, the 8mm and 12mm have been reviewed most favourably. That's another nice thing about telescopes with longer focal-lengths, in that you can get quality performance with all of those eyepieces, including the simpler ones, and for relatively little outlay.
  3. I got this rogue's gallery with my Meade "Polaris" 114/900, and a current model... Indeed, the plastic 2x barlow, and probably with a plastic lens(es) even, introduced considerable false-colour, and with Newtonians being 100% apochromatic, colour-free, in the first place. In addition, the images through the eyepieces exhibited graininess. The telescope, however, is excellent, as I had tested it with my better eyepieces. Did your Meade 114/900 come with a .965" visual-back, eyepieces and barlow?
  4. Those are the times where you'd simply zoom in to capture the full field-of-view. In any event, the goal would be capturing individual objects, not vistas so much.
  5. Prime-focus imaging with a DSLR requires a LOT of researching, trial-and-error, and monetary outlay. It is usually those individuals who dwell under light-polluted skies who are compelled to image rather than observe with eyepieces, but I've digressed. A mount required for imaging with a DSLR is of prime importance. Unlike our eyes and brains, which can compensate for tracking errors, the shakes and wobbles, a camera will tolerate none of that. The camera, and the telescope to which it's tethered, must be held rigidly, like a rock, whilst they track an object during a timed-exposure(s). Else, the images will be soft or blurred. The mount must be able to track the celestial sphere, and in an arc, therefore an equatorial mount is practically necessary; for example... https://www.telescope.com/catalog/product.jsp?productId=116276&gclid=CjwKCAiAnfjyBRBxEiwA-EECLCGiyfb1vSjrpKsiu-Bu11YjwSTDh3-Upa7mzdLXy-goIe0ewuDKgRoCSHIQAvD_BwE That mount supports up to 30 lbs. for visual-use, but only about 50% of that for imaging, 15 lbs.(telescope, DSLR, et al). The mount is far more important than the telescope chosen to mate with a DSLR. A modern DSLR's sensor, a CMOS usually, is much more sensitive than the eye, therefore large-aperture telescopes are not required. Many start out with either an 80mm f/6 ED or triplet-apochromat refractor; a telescope with a short focal-length in any event. It is more difficult to image with a Newtonian or a Schmidt- or Maksutov-Cassegrain. Those are the mirrored options. A refractor, with a doublet or triplet as its objective-lens, is easiest. It would be harder work, and more frustrating, to employ lesser components for imaging with a DSLR; but it wouldn't be impossible. Somewhat near to the stated budget, you can choose an 102mm achromat with a 2" focusser, and a manual equatorial with its RA-axis motorised; for examples... The equatorial mount... https://www.telescope.com/Orion/Orion-SkyView-Pro-Equatorial-Telescope-Mount/rc/2160/p/9829.uts Motor-drives for the RA and DEC axes... https://www.telescope.com/Orion/Orion-Dual-Axis-TrueTrack-Telescope-Drive/rc/2160/p/7832.uts The go-to upgrade, to be had in future perhaps, and for greater ease in imaging with a DSLR... https://www.telescope.com/Orion/Orion-GoTo-Upgrade-Kit-for-SkyView-Pro-EQ-Telescope-Mounts/rc/2160/p/7817.uts The telescope... https://www.highpointscientific.com/meade-infinity-102-mm-altazimuth-refractor-telescope-209006?utm_source=google&utm_medium=cse&utm_term=MEA-209006&gclid=CjwKCAiAnfjyBRBxEiwA-EECLAbBy_jZogwsdCqK9U52ztKgfEgo_Xh63eIEgwadBofZ2xB-MozIchoCnT4QAvD_BwE Now, if you chose to use a webcam-type camera instead, then you can use most any telescope and mount. I take afocal-shots on occasion, by simply hand-holding a small point-and-shoot camera up to an eyepiece inserted into any of my telescopes, and snapping a shot, on the fly; no timed-exposures... Of course, with the afocal method, I'm limited to the brighter objects. If you can hand-hold your DSLR likewise, you can use any telescope on the planet, on a manual alt-azimuth even. All of those images within the collage were taken through this 6" f/5 Newtonian, and on, again, a manual alt-azimuth... https://www.highpointscientific.com/celestron-omni-xlt-150-newtonian-reflector-optical-tube-assembly-ota-31057ota If you can precisely collimate a Newtonian, like that one, you can expect very nice images, during visual-use, or whilst imaging.
  6. This is the actual link to Michael Weasner's site... http://www.weasner.com/etx/menu.html Enter key-words within the "Looking for something on the ETX Site?" search-engine near the bottom of the page. I entered "lubrication", for example, and was led to numerous others' reports on how they had re-lubricated their ETX mounts.
  7. My own, after I cut them down, were about half that length. But cells do differ from one to another. 25mm is how long my springs were originally, therefore you might have to cut those down, as you don't want to set the primary-mirror back too far.
  8. This the pack of springs I got at my local big-box hardware... That is, the likely candidates for the job from the pack. Note how substantial, how thick, they are. Also, compare them to the adjustment-bolt laying before them. I chose two from the third grouping from the left, and the only ones of stainless-steel. I then cut three out of those two to the length required... I then bent the cut ends towards the remainder of the springs... That way, they won't try to slip to the side when compressing them. Keep in mind that you're tensioning a 150mm primary-cell. I don't think that the ones you ordered would tension that of a 76mm.
  9. You don't want the springs to be too large in diameter; not quite twice the diameter of the bolt. You do want the springs to be difficult to compress with the fingers. You should be able to squeeze the springs a little with the fingers, but only very little.
  10. No, not for the adjustment-bolts at least. You want them at the same threaded length. The lock-bolts can be as long as you'd like, and stretching back into infinity even. I replaced all of mine with socket-heads; before and after... I just don't care for Phillips-heads. To me, Phillips-head screws are for permanent fastenings only, and they're not all that great for that, either. They were developed to make driving a screw easier, and faster. It didn't matter about the length of the lock-bolts when I changed over. I wanted them a little longer. You will have to adjust the length of the springs to correspond with the length of the adjustment bolts; again, trial-and-error. You can choose just the right tension in so doing.
  11. Yes, you replace the rubber o-rings with metal springs, and as I did for this reflector... You can see the o-ring there, at left within the image at right, and after it was removed. It's just sitting there, waiting to be cast into the bin. The springs should be heavy-duty, like that used in industry, but not large ones. You may have to cut them down in size even, and as I did. Trial-and-error the undertaking, but just remember, you'll defeating the manufacturer in their wanton indifference towards the consumer. Afterwards, it makes collimating so much easier.
  12. An EQ5-class mount would be an excellent choice, and the sweet-spot among the equatorial mounts. They do get ponderous at an EQ-3 and up. Also, the best EQ-3 is an EQ-5. An EQ-5 weighs only a little more than an EQ-3, yet is much more versatile in the range of telescopes that can be supported.
  13. Again, I'm not certain, as I no longer have my Japanese-made EQ-2 from the early-1990s with which to compare, therefore I only suspect, and strongly, that that's incorrect.
  14. In that any and all eyepieces are pushed over to one side when securing with thumbscrews, then it would follow that the Cheshire, cap, or laser should also be pushed over to one side, the same side, when collimating. That will ensure that the centres of the 1.25" eyepieces will correspond to the centres of the secondary and primary mirrors. You can certainly use a centring-adaptor, but the adaptor will be required when using the 1.25" eyepieces as well, if you want everything spot on. It's not so much an issue with 2" eyepieces, as those are at the lowest powers. Rather, it's at the higher and highest powers where the collimation needs to be precise.
  15. Try to find a 12V marine-type battery, and get a box for it. You can add USB-ports to the box, and other 12V DC connections. You will need to research that... https://stargazerslounge.com/topic/288564-portable-12v-power-box/
  16. If I'm not mistaken, you're referring to the latitude-scale... If so, I carefully lifted it off, and then re-glued it on as true and square as I could manage. I used what I call a squaring-jig, and of my own design... I made it out of narrow strips of thin plywood. It's not that crucial to correct that, however. Now, in so far as the setting-circles, for the RA and DEC, they might as well have been printed with clown faces... Aside from those aspects of the mount, and of far more importance, if the RA-axis is stiff, bound up, or loose and sloppy, you will have to figure out a way of adjusting its lock-nut. You don't have to take the axis apart, but you should at least be able to adjust it. I can't help but think that there is a set of sockets that have thin walls, the kind that would crack and shatter if you used them for automobile repairs. Such a set would be made in China, of course, The set should also be dirt-cheap, and found at discount-houses or other. Back in the late 20th-century, here in the U.S., I used to run across sets like that all the time. If that fails, and if you desire to defeat the manufacturer in that, then you will need the tool that I had described previously.
  17. Yes, I have the same 114/900... Let's take the 900mm focal-length of our telescopes and see what we get. The planets become interesting at 150x and up, up close... 900mm ÷ 150x = a 6mm eyepiece. The telescope is certainly capable of reaching even higher powers, up to 200x, and beyond even whilst observing the Moon's craters, and within those, the craterlets; not to metion the walls of the craters as they slope upward. You can get a 2x-barlow, and combine that with a 12mm eyepiece, and for a simulated 6mm. A 9mm can be combined with the barlow, and for a simulated 4.5mm(200x). In order to aid in the hunt, a 32mm Plossl is also recommended, and for your lowest power and widest view of the sky. Once you spot something or other, you simply pop in the shorter eyepieces and get closer and closer still.
  18. Which telescope do you have exactly, the make and model? I have a 4.5" Newtonian myself, a Meade.
  19. A 9mm Plossl should be allright. Anything below that will have a tiny eye-lens and tight eye-relief. I have a Vixen NPL 6mm Plossl. I have to hold my eyeball right up to the lens, to where it almost touches same, and in order to see the full field-of-view. It can be uncomfortable to use, but the views are outstanding... It's a keeper and a half.
  20. You don't want to go all the way round with a shim, for when the thumbscrews are battened down the eyepiece will be secured slightly off-centre.
  21. Trouble with the 1.26" visual-backs? When the thumbscrews are battened down against the barrel of an eyepiece, that leaves a 0.010"(0.25mm) gap on one side. Simulate that with a partial shim of that thickness, something slippery, and with the thumbscrew(s) fully loosened.
  22. Laser-collimators are generally used for larger and longer Newtonians on Dobson mounts. The cheaper lasers usualy have to be collimated first, and can be more trouble than they're worth. I have one myself, and it is difficult to collimate, and before I can use it for a telescope. In any event, I don't use one to collimate my smaller, shorter Newtonians, like your own. Instead, I use a Cheshire and a collimation-cap, both, and during a single procedure. Cheshire... https://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html Beware of cheaper Cheshires, as the cross-hairs may not be aligned correctly, and cannot be corrected. Collimation-cap... https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html In the case of Newtonians, the peep-hole and cross-hairs of a Cheshire act as those of a sight-tube, and aid in centring the secondary-mirror directly under the draw-tube of the focusser... Then, adjusting both mirrors, you direct their centres towards each other, back and forth until they are aligned... When the cross-hairs of the Cheshire on the outside are aligned with the mirror-image of same in the centre, and both along with the primary-mirror's centre-spot, you're golden. I then use a collimation-cap to verify, and tweak further if necessary... When tightening down the primary's lock-bolts after adjustment, the cap allows you to keep an eye on the alignment to ensure that nothing shifts out of position when tightening. Note how the lighter circle is not centred within the larger black circle. It's askew, off-centre. That is normal for a short Newtonian(f/4, f/5). It is known as the secondary off-setting, and it occurs during a normal collimation procedure. There's nothing you have to do to accomplish the off-setting. Newtonian collimation tutorials... http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/ https://garyseronik.com/a-beginners-guide-to-collimation/
  23. Your CG-3 equatorial mount is an EQ-2. I have a Meade, "Large Equatorial" they call it, and also an EQ-2. Here's my thread on its renovation... https://stargazerslounge.com/topic/319273-meade-large-equatorialeq-2-hyper-tuning/ Now, you're not expected to do everything I did. Just pick and choose according to your ability. You may not be able to access the lock-nut of the RA-axis with a socket-wrench, to free it up if it seems too tight. I had to use a larger pair of needle-nose pliers; heavy-duty, and to adjust or remove the nut. I don't have a 130/650, but I do have this 127/1000 "Bird Jones"... https://stargazerslounge.com/topic/340294-celestron-powerseeker-127eq/ You might be able to glean some help from that.
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