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Alan64

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Everything posted by Alan64

  1. Undoubtedly it has experienced slow sales, which is how I got it for a song; a promotional I suspect: US$299(£236), and from a vendor in New York. I've been aware of its presence within the marketplace for quite some time, but so little information has been forthcoming. I came close to deciding upon the Orion-of-California model, a Synta, as are the Celestron and Sky-Watcher models, at f/12, and all three apertures actually at 118-121mm. I did find this out about the Jinghua: it has a full 127mm of aperture... ...and at f/15, a slightly smaller secondary-obstruction. That, combined with what I thought to be a promotional, made it a no-brainer.
  2. Many times in the past, I have also stated... "A 127mm Maksutov is the 'sweet spot' among the varying apertures of the design; not too small, not too large, just right rather"... A Jinghua Optical Co.(JOC) 127mm f/15 Maksutov-Cassegrain... It is identical to that branded "Bresser", and perhaps the Meade 127mm as well.
  3. The big box is almost emptied, save for this last box...
  4. "I've never had one of those before..." I take that back, as I do have this 2" mirrored-star...
  5. The telescope came with accessories, and a mount to boot. But the mount, an alt-azimuth, will need renovating straight away. I have some material on order for it, although it will not be described nor illustrated until it's righted. Out of the box, the threaded end of the altitude handle was crooked... I "warmed" it up with a mini-torch and straightened it as best I could. I was fearful that it might snap off altogether. Perhaps the torch tempered the soft imported steel, I can only hope. One eyepiece was provided: yet another kit-25mm, and a Plossl. I've never used my 25mm eyepieces, a total of four now from kits, and in preferring a 20mm instead... The red-dot finder... The battery's good, but the chassis shakes and wiggles like a bowl of gelatin. Elsewhere, someone who has one just like it suggested adding springs to the cross-screws. I do have a box of assorted springs, but do I really want to go to the trouble? I have other means. What is this? I've never gotten an accessory quite like this before... Why, it's a dumbphone holder; bizarre to say the least. An empty box... Not unexpected; although as I fished it out I did have high hopes that it contained something lovely. A mirrored star-diagonal... I've never had one of those before, but I now have one with which to experiment and play. I suppose we now know that it's not a Newtonian; drat. But still, what could it be?
  6. Practically all of my life, since I was about nine years of age, I've owned and enjoyed telescopes designed in the 1600s. All I might add to that is: when you've got a good thing going, and for over 400 years and counting, then quit whilst you're ahead. This latest acquisition is one for which I've been longing, and for quite some time. On more than one occasion I've stated... "I plan on getting one of those myself in future." The future has arrived at last... Double-boxed, and expected... <creeeak>... What in the name of James Gregory could it...oops.
  7. Thank you, sir. If your kit was identical to this Prinz Astral 500... https://www.youtube.com/watch?v=eQ0wdFSFZ1o ...then that's an EQ-2 rather, but only a little larger, not by much. I had a Towa EQ-2 myself once... I had given mine to a relation. As far as I know, the telescope houses of Japan never produced an EQ-1. If they did, they certainly weren't as commonplace as the EQ-2. Back then, the 60mm+ achromats were of a considerable length, at f/13 or f/15, and required the stability of an EQ-2, at a bare minimum. The 50mm and even 40mm achromats of that age generally if not exclusively came with alt-azimuth mounts, like this 50mm f/12 of my own... In any event, you should've kept that one, and just as I should have kept my own. Hindsight is indeed 20/20 in that.
  8. Thank you, sir. I'm not quite done with the mount however. There are a few more things to do, and one of those may be in the getting of stainless-steel hardware for that very thing. When I had fastened that hardware, it did feel as though it were in a pinch.
  9. The final images to conclude this thread; I used my relation's Celestron C90 for the photo-shoot. The mount is practically finished. I do plan to eventually to make an eyepiece-tray for the tripod, but not at this time... I'm also wanting to fit a knob onto the RA worm-shaft in lieu of the slow-motion cable. There, the sunlight illuminated the bottom of the front leg; rather lovely... Clear skies to all, and thank you for looking...
  10. I would choose a variable-polariser, rather than one with a fixed percentage, the 13% in question... https://www.teleskop-express.de/shop/product_info.php/info/p321_TS-Optics-variable-Polarising-Filter-1-25--for-moon-and-planets.html There are also other fixed-percentages available, up to 25% I believe. You'd have all the fixed percentages in one unit with the variable-polariser. A variable polariser acts as an indoor light-dimmer, but for the telescope. You simply twist the two halves together to adjust... Now, I'm not suggesting it so much for the Moon, although if the light from same bothers your eyes, by all means. Where I found great success with my own was when observing Jupiter, particularly during its opposition. I was observing Jupiter with a 150mm f/5 Newtonian, the next step down in size from your own. The planet was simply too bright, even at the higher powers, to see any detail. I then integrated the variable-polariser... I could at last see wondrous detail on Jupiter's surface. The filter also eliminated the flares caused by the Newtonian's secondary's spider-vanes. During Mars' fairly recent opposition, the filter eliminated those as well... But there was no detail to be seen on Mars' surface at that time, as the planet was experiencing a major dust storm. Those are digital drawings of what I saw live, and from Bortle 3 or 4 skies here at my home. Those 66° wide-angle eyepieces are sold on eBay, if you have access, and for considerably less outlay; for example, here's the entire set... https://www.ebay.com/itm/SVBONY-1-25-FMC-Ultra-Wide-66-6-9-15-20mm-Eyepieces-for-Astronomical-Telescope/323738641360?hash=item4b6053a3d0:g:SokAAOSwg31abF8r&frcectupt=true A pair of the 6mm and 9mm... https://www.ebay.com/itm/SVBONY-1-25-6mm-9mm-66-Deg-FMC-Ultra-Wide-Angle-Eyepieces-For-Astro-Telescope/362586394038?hash=item546bd54db6:g:UJ4AAOSw64tbnPqE A single 6mm... https://www.ebay.com/itm/SVBONY-1-25-Ultra-Wide-Angle-Eyepieces-Lens-6mm-66-FMC-for-Astro-Telescope-NEW/312505460469?hash=item48c2c6e6f5:g:-cIAAOSw-JJabFUX The full Moon is not usually observed, as there's little detail to be seen. It's during the Moon's phases that drives us wild... But then, why not, as I've observed the full Moon on several occasions... ...including that big "strawberry".
  11. Not bad, not at all. When I take snaps through my telescopes, I sharpen them with a paint programme, but only to match the sharpness seen when observing with the eye and an eyepiece. I also adjust the contrast, and again, only to match what was seen live. For example, I took this shot of the Moon through a 60mm refractor... Now, you may think that sharp and clear, but I saw the minutest of detail within this area of that image during a live view with my own eye and eyepiece... ...craterlets and rilles, hills and dales, seemingly tens if not hundreds of them, but the camera could not capture a single one. Therefore, I think that you've got a very nice telescope there.
  12. Sorry to hear of that. Have you either repaired the flip-mirror cell or bypassed it with the camera-port?
  13. The AWB "OneSky" is the same kit, made by Synta. There is this long-running thread within Cloudy Nights... https://www.cloudynights.com/topic/463109-onesky-newtonian-astronomers-without-borders/ It has a great following. At that price-point, you can't go wrong. But as with all entry-level kits, and advanced ones as well, there are pros and cons. But ignore that, as 130mm of aperture is a wonderful thing, and the telescope's 650mm focal-length will enable you observe the gamut, everything in the sky that the aperture will allow; with the aid of 2x and 3x barlows. Collimation is not all that difficult at f/5. I have a 150mm f/5, and it hasn't been too difficult. Then, there's its compact size, ready to go at a moment's notice. It has a stalk-type secondary rather than a spider-type, and I've found that to be preferable whilst observing with my 114mm f/8... It's nigh near a modern Cassegrain's configuration in that. The main complaint of the AWB "OneSky" is the helical-focusser, and that of the "Heritage" in consequence, but it's not inside the tube, and can be adjusted with a bit of DIY. The tube is removable, and can be placed on a tripod-type mount in future, for improved control.
  14. This 90mm Maksutov upon my larger alt-azimuth, fell over one day. The telescope itself did not hit the floor, as the girth of the mount prevented that... It's not my own, a relation's, but I'm the only one who has used it in an astronomical manner. I don't know if it's out of collimation from the factory, or as a result of happenstance, but it is off a bit according to my collimation-cap. There are instructions online, and the process akin to a Chinese finger-puzzle for those who have yet to attempt the procedure, including myself. But I feel responsible in this instance, so I get to have some fun. Of the three mirrored designs of telescopes commonly encountered within the marketplace -- Newtonians, Maksutovs, and Schmidts -- the Maksutov is the most difficult to collimate, with the Newtonian running a close second. A Schmidt is not necessarily a cake-walk however, but is the easiest of the three. If you have a 1.25" diagonal that came with the kit, and are wanting to replace it with another 1.25", I humbly suggest a star-prism, rather than a star-mirror(dielectric), like this one... https://www.365astronomy.com/Celestron-Diagonal-Star-1.25-in.html The Lacerta appears identical, but I would write or telephone first to ensure that it is in fact a star-prism... https://www.365astronomy.com/Lacerta-Star-Diagonal-1.25-inch.html Then there's this one, and not for too terribly much more than an entry-level dielectric... https://www.firstlightoptics.com/diagonals/takahashi-125-diagonal.html
  15. Newtonians can withstand that sort of thing; a refractor however would not fare as well, nor a Maksutov or Schmidt.
  16. There are only three areas of these entry-level mount-heads, in this instance the EQ-2, that need checking, and oft adjusting upon its arrival... 1. The RA lock-nut... You would simply loosen that one to adjust. Being a lock-nut, it will hold its position wherever you set it. 2. The DEC lock-nut... You would loosen the three screws round, screw the ribbed nut inward or outward to the desired position, then secure the screws. 3. The RA worm-shaft assembly is a bit more complicated, but it's not that difficult really... https://stargazerslounge.com/topic/319273-meade-large-equatorialeq-2-hyper-tuning/?do=findComment&comment=3492379 At a minimum, there should be no dire need to completely disassemble anything. You want those junctures to be without slack and slop, yet easily set in motion. For the lack of a better analogy, these entry-level mounts, and those larger even, are oft as this upon arrival... https://www.completelydelicious.com/wp-content/uploads/2015/01/IMG_4124.jpg ...a work still in progress.
  17. Glamour shots... I couldn't be more pleased with the outcome. The unions throughout are wonderfully rigid and tight, yet requiring little effort to set them into motion... I don't think that I'll ever extend the legs farther than that. I may even install stops, and as my larger wooden tripod had been originally equipped, but something a bit more effective than just screw-heads. I now have a can of Diet Coke® as my new prop; for perspective, a sense of scale. Just how small is the tripod? I am toying with the idea of a pier, but perhaps not quite 8"(20cm) in height as two of my other mounts possess; perhaps 6"(15cm) instead... Now to finalise the mount-head. I'm also waiting on a 5"(13cm) anodised-black dovetail-bar from China for this mount's telescope. I just can't and refuse to use this one... ...that from a modern Meade achromat.
  18. What was once hidden underneath that drab finish has now been revealed; before and after... The legs were reassembled, and just as they had been before.
  19. Done... One last hurdle to overcome, and where the pins of the old hardware were removed, as the threaded holes of the lock-nuts rose above the ends of the screws... What to do about that? Where there's a will there's a way. I simply ground down one of the six flat sides of the lock-nut until it lowered into position... Also, the diameters of the screws' heads required reducing, and to clear the surface of the braces as they slid into place. You can see there on the right where the paint had been scratched before. Gone is that ubiquitous slack and slop that plagued these older mounts(the current ones as well), and right up to the eyepiece of a telescope... The lock-nut for the larger screw is a good bit thicker. I couldn't find jam-type lock-nuts for that size, only for the smaller as seen. They are available online however; perhaps one day. Lock-washers instead of flat-washers were integrated with the lock-nuts, and for peace of mind. Done...
  20. I had a hiccough, and a fortunate one... Well, would you look at that. The attachment points differ in position. I've got to know how exactly where to attach the braces' tabs to the arms of the spreader, and so to preserve the same angle of the wooden legs as those of the aluminum when folded outward, or near enough. I then made a diagram with my old "CAD" programme, Paint Shop Pro 6. I tried version 7, long ago, then went back to 6. When you've already got a good thing going... The arms of the spreader must be somewhat longer. From that, there, and indeed near enough... ...or 25.4mm. <hiccough>
  21. The most challenging aspect of this part of the project was in the marrying of the old hardware of the wooden legs to the spreader-assembly of the much newer kit. I removed the steel-pins of the old braces, then went to my local hardware... After I set to work from there, I realised that the loops at the ends of the arms had to go... The ends were hammered flat and smoothed. You can see there at upper right where I needed to batten down a lock-nut, yet the loop was in the way. Scoring with a diamond-wheel, then a hacksaw, removed them rather quickly. As a result of using said tools to prepare these parts, a nick here, a scrape there, all got a fresh spritzing with satin black, and to prevent rust...
  22. Springtime chores had placed this project on hold for a spell -- milking the cows, repairing the ox-cart and the stone wall round the homestead -- those sorts of things. The new-old legs finally received their first coat of satin spar-urethane... ...then a second coat on select areas, and where wood does not contact wood... After the varnish cured, brass was placed on the tops of the center-legs, and to protect the wood when slammed up against the edges of the yokes of the tripod-hub... I considered aftermarket tips for the legs, but upon closer inspection, and after a trip to town, the original tips will be fine. But instead of re-stapling them, I decided to secure them a bit better... ...and of stainless-steel.
  23. After a "wild" early-morning session, I left the tube of this Newtonian outside pointed straight-up, at the zenith, then went to bed... I dreamt during that time, and of going outside to find the telescope full of water. In the dream, I must have poured a couple of gallons out. Upon awaking, I went outside, and it had indeed rained whilst I had slept, but there was, at most, only a tablespoon or two of water within, and with no harm done. I took the telescope inside, blotted what water I saw, allowed it to dry, then all was "right as rain".
  24. You have a Sky-Watcher(Synta) 130mm f/7, and I have this Meade(Ningbo Sunny)114mm f/8... Both of our telescopes have a 900mm focal-length, an EQ-2 mount, and spherical primary-mirrors. At the longer focal-length of my own, I have been told that the telescope is at 1/5th-wave if perfectly spherical. Therefore yours, at f/7, should perform within Rayleigh's 1/4th-wave criterion as well, and diffraction-limited. But it must be collimated well. Mine, fresh out of the box, gave me practically tack-sharp views. "Diffraction Limited" is stated within the specs of the Orion-of-California variant of your own, the Orion "SpaceProbe" 130, and also made by Synta. In order to use an inexpensive motor-drive with your mount, you must adjust the mount, and to where you can twist the RA worm-shaft with your fingers, and with little effort... Else, the plastic gears and their teeth within the drive will break and crack, and the motor itself can burn out. These mounts generally arrive bound-up and tight. If yours seems a little too tight, loosen it up. The mount is a mechanical thing, a machine, and consisting of nuts and bolts to hold it together.
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