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Alan64

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Everything posted by Alan64

  1. Yes, and then there's this one... https://astronomy.tools/calculators/field_of_view/ ...similar. Enjoy.
  2. I had been looking at the various dyes online, rather than stain, and for these tripod-legs. Some were water-based, but I didn't want that. And there in my own backyard, in a cupboard actually, a bottle of alcohol-based burgundy, and practically full... ...and tested there on a scrap of maple. Incidentally, I still don't know the species of wood of which these legs were made. I'm thinking luan, meranti or "Philippine mahogany"; all the same I think. In any event, it's rather dense, inflexible... ...and quite strong for such small stock.
  3. I don't use a 45° Amici for stargazing. That's simply the diagonal that came with the C90. But upon studying the images more closely, perhaps a RACI would be best, particularly when the telescope is pointed at or near the zenith; my apologies.
  4. An obsessed amateur does what an obsessed amateur must... "Gruelling" was not the word, rather "exhausting", "excruciating", and in stripping those legs. It was absolutely, positively, no fun, and to the point where I don't feel any sense of reward after having done so. But, they are pretty nonetheless. I've decided not to worry it to death in getting every last speck of the old stain out of the pores. The colour to be chosen will be medium-dark, after all. I want this colour...
  5. A Maksutov requires a "seeing-eye-dog", or a seeing-eye owl, when attempting to navigate the sky with the Maksutov's rather long, drinking-straw-like focal-length; in manual mode, on the fly... If a finderscope, get a straight-through 50mm... https://www.firstlightoptics.com/finders/skywatcher-9x50-finderscope.html The RACIs were developed for Newtonians.
  6. I have this Meade 8-24mm. It's bigger than a bread bin... I got my own last year for less than USD$65. The views are not bad, not at all, but I haven't used it much, like once. Some do barlow zooms. I suppose they get some benefit from so doing. Incidentally, whether one uses a Plossl and a barlow, or a BST planetary or "Starguider", no matter, as a barlow is being employed, whether separately, or integrated.
  7. Ah, but you lose the grain of the wood in that. These legs are going to get something special, colour-wise.
  8. Welly well, that worked a charm, a treat... The bulk of the old finish is gone, but traces remain. I may give them a second coat, but outdoors, as this stuff is not particularly nose-friendly, even with a ventilation-fan running, although that did help, and from turning me into a vegetable.
  9. Yes, the legs are practically identical... The tripod-hub of my own has the same split-yokes, but not much of a base for a mount head... Yes, all of these off-shore equatorials, particularly the entry-level, must be loosened throughout, and before even thinking of adding a motor-drive. The greater the level of attention, the better for the drive... https://stargazerslounge.com/topic/319273-meade-large-equatorialeq-2-hyper-tuning/ I still have some more to do to it, however.
  10. Thank you. Yes, as I had suspected, many do.
  11. That's kind of, sort of, the colour of..."circus peanuts"... ...a pinkish-orange, like a Padparadscha sapphire as well...
  12. Whatever the nature of this finish, it's not particularly lovely... If I had to guess the colour, I'd say "peat".
  13. The other two will need to be adjusted like that. The sawn surfaces will be faced with brass sheet, epoxied. That's the old hardware from the Tanzutsu, the butterfly-nut specifically, and all of zinc-plated steel. In so far as the integration, that experimentation with the spreader is just that, and nothing more.
  14. I've had these two small achromats for a few years now. Both were made in Japan in the late '70s to late '80s, give or take; a used Tanzutsu(left), and a new old-stock Milben(right)... Both came with wooden tripods, and the archaic, basic, yoke-type alt-azimuth heads. Hmm... A leg of the Tanzutsu(left) compared to that of the Milben(right)... The leg-clamps of the Tanzutsu(left) are deluxe... In addition, the legs of the Tanzutsu have a smoother finish, are more dense, thus heavier, and noticeably so. Hmm...
  15. For the forward portion of the RA-axis, I made a small bronze washer for it... ...and for an ever-hopeful buttery-smoothness of operation, particularly when swinging the telescope around and about. That's where it stands to date. I have to make two more bronze washers for the DEC, and adjust and polish a ready-made as well. Then, I also have these, for the axes' lock-nuts and the worm shaft, to adjust and polish... ...and to replace what Synta had provided.
  16. Fore of that, something had to be done, and to complete the RA-axis; the other side...the other side... These are the only two of the original washers that I will be using, and for the RA setting-circle... They only isolate the steel of the DEC body and the aluminum RA-gear from the setting-circle itself; nothing else. The clear washer(difficult to see) rests on that narrow step of the flange... ...then the setting-circle rests on top of the clear washer. The surface of the circle is then flush with the surface of the wider step above the much narrower one. The black, rubber washer eventually presses against the setting-circle to keep it in position, with the rubber washer to eventually nest within that recess, as shown. But what about that wider step, and that narrow, circular bearing-surface of the DEC body that I had to strip of its paint? Yes, it had been painted as well... That's where the aluminum of the RA-gear grinds against the steel of the DEC body. Now, I can't add a thrust bearing there, let alone bronze washers, as I'd have practically none of the gear's flange left to clamp when needed, and illustrated here courtesy of my spare "AstroMaster" CG-2... You can just barely see the tip of the flange peeking out there...boo! Now, with just a thin bronze washer... I see it! I can see the tip! Hooray! But it's not enough really, and all Synta's fault. Even with that washer removed, you still get only half a tip. Incidentally, look at what someone had done to the RA-gear of this spare mount-head... Isn't that dreadful? Someone had had a heavy hand in that. We all need to take a deep breath on occasion, and step back and away from these diminutive mounts, and contemplate, as I'm guilty of doing something like that myself.... I had never had an EQ-1 before; an EQ-2, yes. How was I supposed to know that that adjustment-bearing was made of aluminum, along with the 2mm set-screw that I failed to notice, and that had to be loosened prior? To wit, this was the only thing I needed from the spare... Isn't it lovely? When submitting my problem to Celestron, I had told them that both axes and the worm-shaft of the original kit were bound-up upon arrival, which they were, and I also told them what I had done as a result. It was very good of them in having taken care of that under warranty, given that it was partially my fault, too. But as it has turned out, I won't be enhancing the "AstroMaster" CG-2 after all. What a waste of time, that was.
  17. I've tried to use my left, and I could if I gave it a chance, after practising, but my right won't allow it.
  18. Thank you, Fabio. Visual always, and forever, but with an occasional afocal shot to demonstrate how a live view appears through whichever telescope is mounted upon it at the time.
  19. The thickness of those extra parts amounts to a hair less than 4mm... ...not too terribly thick at all, eh? This discovery was not surprising, expected even... The RA bore there, circled in red, is slightly larger than the RA shaft above. As a result, there's slop, and an appreciable amount. To make matters worse, the 11mm-long bore is slightly conical in shape; there will be no placing a shim of any sort there I'm afraid. But I found a way around that. Note the larger, stepped bore; with a shim(shown) of .015"/.38mm-thick PTFE(Teflon)... With that, the slop was completely, totally, and utterly eliminated, and whilst bypassing the inaccuracy of the innermost bore... I lucked out on that one, and you can, too. Incidentally, there is an alternative to bronze for the washers, and instead utilising PTFE, in sheet form. It's easy to cut, with scissors and a craft-knife, and it can be scribed upon with an ultra-fine permanent-marker, which is not very permanent at all when the ink is wiped away with rubbing-alcohol afterwards... https://www.directplastics.co.uk/ptfe-sheet A small-circle template is a great help when making your own PTFE washers. This is the one I use... https://www.amazon.co.uk/Helix-Small-Circle-Template-37168/dp/B00AETPZFW ...it works a charm.
  20. Yes, like these wonderful barlows... https://telescopes.id/en/50-barlow However, that GSO 3x-barlow listed within is a bit long, and unsuitable for a small Newtonian. The Meade 3x mentioned previously is a "shorty", and a better choice in that regard.
  21. I've had a sheet of .008"/ .20mm phosphor-bronze for quite some time, but I always need to go to my local hardware at the county seat to get my thicker washers of sintered, or powdered, bronze... As they come, one almost fits over the flange of the aft portion of the RA-gear, but not quite... But after wallowing the I.D. out slightly, and polishing it... ...it then fits like a glove, along with this much thinner washer that I crafted of the phosphor-bronze... ...the result? Nigh a Swiss watch this mount should tick beneath the starry dome.
  22. Quite right, and precisely what I hope to convey in this undertaking, but only for the smaller telescopes of course.
  23. I reside on the verge of the American west, in the eastern portion still, but just barely, and the two halves separated by the Mississippi river, the largest in the U.S. I think that that may play a part in why I received these from California on the 20th, and when they were scheduled to arrive on the 22nd. Needle-thrust bearings, one for the RA-axis, and the larger for the DEC... Aren't they lovely? It's not so important to place one within the DEC-axis, but whilst I was at it, why not. Note the DEC flange there, and with its paint still upon it, as well as that upon the bores of the RA. But do I want steel bearing against aluminum and steel?
  24. Lastly, in preparation for the hyper-tuning, these surfaces were stripped of their paint as well, inside and out here... That brass rod will replace the rusty, steel clamping-pin, after it's cut to length of course. The flange of the DEC shaft was also stripped... Rust at the tip of the counterweight-shaft, inside... That has been rectified. There are also portions of the DEC control with rust, and those will be cleaned and lubed as well. Thankfully, those are only two instances of rust that I've found within this mount-head. In addition, those instances were not surprising, expected even.
  25. You will enjoy the 130mm aperture of that kit. It has a short focal-length however: 650mm. A 2x-barlow will effectively extend that to 1300mm; a 3x to 1950mm. That way, you won't have to resort to eyepieces of short focal-lengths, with tiny eye-lenses and rather short eye-relief, like this 4mm... Instead, you can place a 12mm into a 3x-barlow... ...which will simulate a 4mm, and at a power of 163x with the Sky-Watcher "Heritage". A 130mm aperture is actually capable of up to 250x, especially when observing the Moon. Let's see what that would take... 650mm ÷ 250x = a 2.6mm eyepiece Here's one of those... https://www.365astronomy.com/2.5mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html ...and another... https://agenaastro.com/bst-1-25-uwa-planetary-eyepiece-2-5mm.html Now, those types of eyepieces are known as "planetaries", and are quite powerful. They also have a barlow built in to them, so you wouldn't need to combine a separate barlow with those. Also, note how my eyepiece/barlow combination illustrated above appears remarkably similar to those planetary eyepieces. They have larger lenses through which to look, too, and rather generous eye-relief. If you're unable to acquire those types of eyepieces in your locale, then you can certainly consider a 3x-barlow in addition. You can combine a 9mm Plossl with the 3x, for a simulated 3mm, and for a power of 217x. Where there's a will there's a way. When considering barlows, don't get the least expensive ones you can find. They don't have to be the most expensive either. Look for your barlows among the brandings "GSO", "Antares", and "Meade" perhaps. Here are the Meade 2x and 3x barlows available in the U.S.... 2x... https://agenaastro.com/meade-series-4000-126-1-25-2x-short-focus-barlow-lens.html 3x... https://agenaastro.com/meade-128-3x-barlow-07278.html Agena Astro ships to Indonesia, and for half the price of one of those barlows. I do realise that there may be other costs incurred, of course; customs, duties, et al. Plossls are the minimum standard in performance eyepieces, and they would play nice with your f/5 Newtonian. Look for GSO Plossls. Keep in mind that a telescope must work harder as you go higher in power, and the collimation of the Newtonian must be precise for sharp and pleasing images at those powers. The atmosphere will play its part as well in that.
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