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Alan64

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Everything posted by Alan64

  1. You do need to throw the mount-head back a bit until the pointer(outlined in red) points to 53° N... 53° is in between the first and second white indicator-lines after the 50°-mark. Once you set it to your correct latitude, you'll should never have to touch it again; unless you move or travel considerably north or south from where you are now. When setting the latitude, you are pre-aiming it at Polaris, the North Star. Once you take the mount outside, Polaris will be in the northern part of the sky 53° above the horizon; above the tree-line, where the trunks of the trees meet the ground. You must level the mount, with a bubble-level, and easy enough to do, then rotate the mount-head side-to-side, perhaps the tripod as well, until the mount-head's RA-axis points to Polaris.... When imaging, you'll probably need a polar-alignment scope, which screws into the back of the RA-axis... https://www.firstlightoptics.com/sky-watcher-mount-accessories/skywatcher-polarscope-for-eq3-2-eq5.html This is what you'll see through the scope... See where "NCP" is, there in the centre of the reticle? That's the North Celestial Pole. Polaris is very near to the NCP, as you can see. The scope is not illuminated however, unfortunately, but I think you can use a small torch to illuminate it. You want to get Polaris, the actual star, within that tiny circle next to the word "Polaris". The polar-scope itself, however, has to be aligned with the RA-axis, and that will be described within the instructions that should come with the scope. Here's the reticle close-up...
  2. Some thoughts upon your new acquisition... The EQ-5 is the sweet-spot among equatorial mounts; not too large, not too small, just right. You can attach all sorts and sizes of telescopes, large and small, for most any purpose, and upon just one, single mount; no need for a collection of mounts, save perhaps an alt-azimuth, for that grab-and-go ease when travelling or other. A manual EQ-5 has a distinct advantage over the others. If the computer or motor(s) fail on an HEQ-5 or EQ-6, they would be dead in the water until repaired, and parts for those are costly; a king's ransom even. With the manual EQ-5 fitted with a motor or a go-to system, you'd be able to strip them off, as though they were clothing, and use the telescope manually with the slow-motion controls. Your 150P won't know how to act when mounted; held fast and rigidly, and ready to sail the celestial seas. Know your mount, and once you get to know it well enough, you can think about making it the very best it can be; just a little something to tuck into the back of the mind for the future... https://www.youtube.com/watch?v=8tZ58AVVyuQ&t=1166s That mount is the same as yours, but with the go-to kit fitted. The metal construction of the mount is the same.
  3. This is the only video I could find, for the manual version... https://www.youtube.com/watch?v=0WqsmXpTqYk&t=375s This video may be helpful as well... https://www.youtube.com/watch?v=yHGmzpsChcg&t=525s How to use any equatorial... https://www.youtube.com/watch?v=v5tfQ7v3GL0 There are only two major parts: the tripod, and the mount-head; then all of the other, smaller bits and bobs to complete it.
  4. That's a good question. Not for visual, but I think that imagers prefer both. You will need to research that online.
  5. The drawtube is completed. I elected not to bother with flocking the tip of the rack... In any event, there will no longer be a reflective tip aimed at both mirrors. On the underside of the focusser's housing, round the opening and the edges of the PTFE strips were matte-blackened... The focusser completed... Quite frankly, I don't think that much of what I had painted will jut into the optical-tube during actual use, if any at all... ...but better safe than sorry.
  6. That will be all the equatorial you'll probably ever need... https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-eq5-deluxe.html You can wait and save up for the go-to upgrade kit, or tide yourself over by motorising just the RA-axis... https://www.firstlightoptics.com/sky-watcher-mount-accessories/single-axis-dc-motor-drive-for-eq5.html The extra part there to the left of the motor would allow you to disengage the tracking, and without having to disconnect the motor from the mount. It also comes with a hand-set that's not shown. The eye and brain can deal with shakes and wobbles, but a camera cannot. A camera must be held rigidly, like a rock, during timed-exposures; else, the images will be blurred or soft. That importance cannot be overestimated... You get the picture, pun intended.
  7. That coincides with spec; 3.8 kg for the plastic version. Your Nikon D3500 weighs about a third of a kilogram, if that's the camera you intend to use; not particularly heavy. I've been wanting that same go-to mount, for visual-use; perhaps a web-cam, definitely afocal-shots through an eyepiece. My Orion(Synta)150mm f/5 weighs 4.08 kg, but I would never place it on that type of mount. It's not just the weight, it's the bulk, and perhaps the moment-arm effect. That type of go-to mount contains plastic gears, with plastic teeth. I'd be afraid of breaking or cracking them, and wearing out the motors prematurely. The harder a motor has to work, the more strain it undergoes, thereby shortening its life. Go-to is fine thing to have, mighty fine, therefore I understand how drawn you are thereto. In the end, it's your decision. If you get the manual EQ-5, you can upgrade it with a go-to add-on in future. In the meantime, you can simply motorise the RA-axis to automatically track.
  8. The 150mm f/8 OTA is the 150PL, the "L" meaning "long", and out of the question of course. However, the 150mm f/5 that was once bundled with the "Star Discovery" had a plastic primary-cell and focusser, so as not to strain and wear out the mount's gears and motors... https://www.youtube.com/watch?v=mhhs65AWdCk Those aspects of a current 150P OTA, and that of the OP, are of metal; considerable extra weight. A 130P, or even a 130P-DS, would mount on the "Star Discovery". Otherwise, with a full-blown 150P, go with an EQ-5; nothing less if astrophotography of any type is to be pursued.
  9. I had gotten a laser-collimator a while back, and touted as having a triplet-lens for a tighter spot; "next generation" it was purported to be. It was purchased off of eBay for less than US$30. It arrived mis-collimated, of course. I made a jig for it... The unit touches no wood, only PTFE(Teflon); a strange thing I had crafted. I replaced the set-screws with "thumb-screws", and only then managed to get it collimated... Afterwards, I used it to check a diagonal, and to align an achromat's focusser; that's all. Many years before, I had gotten this passive set of tools, from left to right: a Cheshire(without cross-hairs), a sight-tube(with cross-hairs), and an auto-collimator... Modern Cheshires with cross-hairs are actually combination-tools, which is fine. I want one, but I'm in no hurry. I use the sight-tube when collimating, and a collimation-cap to tweak... At 50x per inch of aperture, I see glory, limited only by the atmosphere; with a 127mm f/3.3 to f/4 spherical-primary and a 4mm symmetrical-Ramsden to boot. With larger, longer Newtonians and Newtonian-Dobsons, I suppose that there's merit in using a laser, in that our arms and hands and fingers will reach back only so far. But then, how in the name of Newton was this collimated, and way back when... You get the picture, pun intended.
  10. In that case, all the better. I prefer rack-and-pinion myself. I do have a Crayford, just one...
  11. The drawtube was carefully masked off, and the bare area satin-blackened... Only one moderate coat was applied, as you don't want it too thick. Once the paint cures, in about a day, the sides and the stop-block of the rack, and the rim of the tube's opening, will be matte-blackened. The tip of the stop-block will be flocked however.
  12. The procedure works particularly well with metal focussers... ...but that is a rack-and-pinion, and as the plastic unit that I'm working on currently. The adjustable bearing, there at the top within the image at far left, allowed for precise centring, with a tolerance of +/- 0.5mm all round. However, I believe that your focusser is a Crayford-type, and has set-screws to adjust its alignment. Although, there just might be a way to improve it nonetheless via this method. This is a distributor of PTFE sheet there in the UK... https://www.directplastics.co.uk/ptfe-sheet The 0.25mm, the thinnest they carry, is nigh the equivalent of a sheet of .010" that I have, and at 0.00985". I've used that slightly thicker within these projects; 0.015" and 0.020". These are the materials I use when working with the PTFE... The roll of clear tape is double-sided. The aluminum-foil tape is that used for HVAC systems, air-conditioning and heating. You may not need the aluminum however. It is only to build up the substrate of the focusser's housing. It all depends upon the spacing round the drawtube when inserted. The aluminum tape does allow for fine adjustments, as it's even thinner than my thinnest sheet of PTFE(0.005"), and at 0.0035" to 0.004". If the spacing is rather tight, then all you'd need is a single layer of double-sided clear-tape applied to the housing's surface, and then the appropriate thickness of PTFE. In addition, all bare surfaces to be joined must be wiped down with either 91% rubbing-alcohol or !00% acetone, and for proper adhesion. If you apply a second layer of aluminum on top of the first, then the first will need to be wiped, and so and so on; also, the surface of the PTFE before pressing it onto the double-sided tape. The PTFE will lift straight up from the double-sided tape easily enough, perpendicularly, but when pulling the PTFE parallel to the tape, it will not budge in the slightest; good thing that the drawtube slides in and out, bearing against and parallel to the PTFE.
  13. I neglected to mention, within my last post, that at f/4 the condition of the focusser is most critical; more so than an f/5, f/6, f/8, et al. It is of particular importance when collimating, and of course, whilst observing. The drawtube was prepped, first by racking the tube all the way inward, then taking a hobby-knife and describing a line all round the tube where it meets the underside of the housing. That lowermost portion of the tube is then sanded, and with 220-grit in this instance... ...including the sides and tip of the rack. Then, the interior of the tube was sanded, and the tube washed, dried, and masked off... The interior of the tube was then matte-blackened... Isn't that lovely?
  14. This is one of the worst plastic focussers, and with which I've ever had to tussle... Hours I spent today, installing the drawtube's bearing materials, ripping them out, then re-installing them. I had to use several layers of aluminum-foil tape, to build up the substrate. However, I had to step the layers, a partial length here and a full-length there... ...trial-and-error, over and over. Now, the drawtube racks in and out along its entire, albeit short, length straight and true, smooth as butter, and with no slop or binding whatsoever. I had almost given up hope, but now, I don't how to act. Now to re-blacken the interior of the drawtube, and satin-blacken that part of the drawtube which descends into the light-path.
  15. And now for the ugly side; the touch-ups for the optical-tube... Scratches... Filled finder-holes... Where the dovetail-bar was attached... Where the primary-cell mounts... The rattle-can paint isn't as black as the original... But under normal lighting, and certainly in the dark, they shan't be noticed. After all, this isn't an Aston-Martin.
  16. The optical-tube has been, at long-last, completed... It will be a day from now however before the tube can be handled, and for the gloss-black paint to cure, but I do not have a pressing need to handle it. I may now tend to the focusser, finder-base, and dust-cap here on out.
  17. Never again will I buy another less-than-$1 rattle-can of Wal-Mart's house-brand. I shook the very devil out of that can, and still the paint lacked enough pigment to brush on even five times to cover. So, I got a rattle-can of Rust-Oleum 2x "Ultra Cover" gloss-black, and to touch up the tube all over; filled holes, and scratches made by the tips of the bolts used to mount the tube-rings to the dovetail-bar. I need to grind those down a bit more. I had stupidly rotated the tube within the rings, whilst having forgotten about those bolt-tips needing more work. The first touch-ups have been applied. In about 30 minutes I'll need to apply a second and final coat, then the tube will be completed. You can see where one of the filled holes is... It looks as though there's a screw-head rising up off of the surface. I just want them sealed, along with those scratches. It shall be pretty enough in the end. Pretty is as pretty does.
  18. I have the PS1000. Avoid it like the very plague. This rather... https://www.firstlightoptics.com/reflectors/skywatcher-heritage-130p-flextube.html ...but not the 100P and at f/4. That one is configured as an astrograph, in disguise.
  19. The Towa #305 is a 6" f/15 achromatic-refractor with an EQ-2 equatorial mount. These are the hits when I "Google" a Towa #1024... https://www.google.com/search?q=towa+model+%23+1024&rlz=1C1CHBD_enUS778US778&oq=towa+model+%23+1024&aqs=chrome..69i57.7039j0j8&sourceid=chrome&ie=UTF-8 Is that one a Newtonian, a reflector, which uses mirrors instead of a doublet-lens? Do you have a photograph of it to share, or the listing itself? Curiouser and curiouser... I have a Celestron "PowerSeeker" 127EQ... ...but I don't recommend them to beginners. For the record, I got mine on purpose, rather than by accident. I also have a 60mm f/15 achromat, just like the Towa #305, the telescope, but mounted on an AZ-1 alt-azimuth...
  20. Methinks the Tasco reflector is formatted with a .965" focusser. It could be upgraded to a 1.25", and perhaps without having to get a somewhat larger secondary-mirror. Do you have a photograph of your present telescope to share with us? For example, this is one of my older telescopes on a wooden mount... ...and it uses the old-style, narrow-view .965" eyepieces.
  21. "The many ways of collimating are as the number of stars in the sky." - Confucius
  22. I've no idea as to the type of secondary-hub set-screws that came with your telescope. In any event, if you can't grab one with two fingers and twist and turn it, then they need to be replaced. These are the sets-screws, at right, that I replaced with the cap-bolts, at left... You want them to stick out far enough to grab a hold of them. You can get those cap-bolts either online or from your local hardware. The goal is to eliminate a tool between the screws and your fingers whilst adjusting them. The shorter the focal-ratio of a Newtonian, the more difficult it is to collimate it, and an f/4 is quite difficult, but not impossible. When working with the secondary, you have to show it who's boss, and with a gloved hand(so as not to get grease and oils on anything). Illuminate the tube with a diffused light-source... Back all three set-screws off and away from the mirror-and-stalk, and with your fingers. Whilst peering through the peep-hole of a Cheshire, you then grab and orient the secondary-mirror with the other hand until it appears as a nigh-perfect circle, and centred directly under the focusser... You than finger-tighten the set-screws to keep the mirror in that position. You do not torque them down at this point. You want those four "pie slices", as divided by the cross-hairs of the Cheshire, to be of the same size. Note the use of the orange construction-paper that I used to block the primary-mirror during that exercise. If the mirror is not centred under the focusser, and perfectly, such is accomplished by the larger screw, usually spring-loaded, there at the centre of the hub... It moves the mirror back and forth along the length of the telescope. The secondary-assembly is that one part of the telescope that gives the most fits. The mirror of same tilts and rotates in most every conceivable direction, but it must come to rest in only one position, and as shown. Once that's done, you then slightly loosen the secondary set-screws, then simultaneously tilt both mirrors, the primary-mirror with its adjustment-screws, towards one another, carefully and slowly, and until their centres line up... Note the lovely f/4 off-setting there in the centre, which is normal and occurs automatically during a collimation procedure. Off-settings are necessary for Newtonians of shorter focal-ratios. Fortunately, again, they occur automatically; although some do tweak that, so I've read. When the cross-hairs of the Cheshire(on the outside), and the mirror-image of the cross-hairs(centre), along with the primary-mirror's centre-spot, all line up together, as shown, you're golden. It is at that time that you batten down all of the adjustment-screws, of both mirrors, whilst keeping a sharp eye on that scene to ensure that nothing moves out of position when so doing. Here's the view of that same scene through the collimation-cap... You then take the telescope outdoors, and see glory, just as I have and do still with my own Newtonians. But then, for longer tubes, two people may be required to adjust both mirrors simultaneously, one stationed at the front of the telescope, and one at the back. There is also the option of one person going back and forth, and until the process is completed. As I understand, laser-collimators allegedly make that aspect easier. Therefore, if, in the end, and regrettably, you choose to stick with a laser, ensure that the laser is collimated beforehand.
  23. Well, I just ordered that Barska 70/300 kaleidoscope a while ago. We'll see. If it doesn't pan out, I'll still be able to observe Sirius... https://www.youtube.com/watch?v=Ou_1Ijx0p50
  24. I have a CG-2(EQ-1), as well as a larger Meade EQ-2, and what Meade calls their "Large Equatorial", but it's nothing of the sort. The EQ-1 is the smallest on the planet, and with the EQ-2 only the next size up. The largest is an EQ-8, and then there are the even larger ones within the professional observatories, staggeringly large. Your CG-3 is the same as my Meade, and an EQ-2 as well. I have a Celestron CG-4, which is an EQ-3; just a bit of rambling there. Pay me no mind. Yes, I have that same 9V-battery motor-drive, although I haven't used it yet; and yes, the Baader 32mm is among the choices at that focal-length. A while back I was wanting a 32mm myself, and had decided on the Baader, but I was swayed towards the Vixen 30mm. Quite recently, I just got another, and a 32mm this time, a GSO... This is the same eyepiece, there in the UK... https://www.365astronomy.com/32mm-GSO-Plossl-Eyepiece.html
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