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Cosmic Geoff

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Everything posted by Cosmic Geoff

  1. Check the manufacturer's spec sheets. A 8" Celestron SCT is not heavy at all.
  2. Check whether the mount can be used with an optional cabled handset. I learned to distrust WiFi when they installed it for the laptops at my last place of work and then had to rip it out and cable them because of electrical interference. A scope will last a very long time (many decades), while electric or electronic mounts have a limited life before they break down or become so obsolete nobody wants to use them. Just like cars or computers.
  3. You do not need to table mount a small GoTo scope. I have tripod mounted Celestron Nexstar GoTo scopes, a 127mm Mak and a 8" SCT and I mostly observe sitting down. The eyepiece position on these does not move a lot and you can get to it while sitting, particularly if you have a chair of variable height (which some observers use but I don't). It is actually much easier to see if you sit rather than stand while trying to stay in position and not bump the eyepiece.
  4. You would have a more pleasant user experience with a mount that has a capacity of more than 5Kg and easily supports the Heritage 150p. I appreciate it may exceed your budget, but putting a 6" Newtonian on a EQ-5 Synscan would not be considered over-mounting, and would give a far more rigid setup than the mounts you cite. I have used lightweight mounts and an EQ-5 mount with small scopes and the difference is like rubber vs. scaffolding.
  5. I used to have a 200p Newtonian on an EQ-5 mount and heartily disliked this combination, so I understand that you may want to dispose of it. I would not recommend putting the 200p on the lightweight Nexstar mount. No good ever comes of overloading a mount. On the contrary, the HEQ5 is reckoned to be a more suitable mount for a 200p. You might consider getting a small scope that suits the Nexstar mount (and does not overload it) as a grab'n go or travel setup. I kept the EQ-5 as it is an all-purpose mount that will rigidly mount any small or portable scope up to 9Kg, even though I do not use it so much.
  6. I recently took a 102mm f5 Startravel refractor and manual alt-az mount to a public astro event, along with a couple of cheap eyepieces. I aimed it at Jupiter, the Moon and Saturn. The public, young and adult, who had a look through it, were suitably impressed. So you probably don't need much for that initial 'wow' factor.
  7. That is certainly possible. I once re-figured a 4" low-quality telescope mirror myself, a long time ago. Unless the focal length is very short, it probably requires re-polishing rather than re-grinding. Thw question is, is it worth the bother? There is a suggestion that this is a Bird-Jones design whick means that the focal length of the mirror is a lot less than 1000mm. Even if you can successfully re-figure the mirror, the telescope tube might require some adaption (made longer or shorter) to get the reworked telescope to focus. My advice would be, that unless you are determined to attempt this as an experiment or optical project, you should use the telescope as it is, and look out for another second-hand telescope that better suits your needs. It is possible to buy new mirrors, but usually in larger and more desirable sizes, and there is a site selling cheap parts from smaller telescopes, whose name escapes me at the moment, who might have a suitable mirror or complete tube assembly.
  8. I tried the above solutions but the problem persists.
  9. You should not need the Barlow with such a long focal ratio instrument. I have tried using a Barlow with my f10 SCT but found that it rarely gave any improvement. ZWO sell inexpensive IR-cut and IR-pass filters to match the ASI224MC camera. You will need the IR-cut filter to get a correct colour balance in colour images. You may find a flip-mirror diagonal of great assistance in locating and re-finding some targets. And don't forget that essential piece of equipment that manufacturers don't like including - the dew shield.
  10. While using my Celestron X-Cel LX 9mm eyepiece, I noticed a black flake obscuring the view. On trying to get rid of it I established that it is definitely not on or in the 1.25" nosepiece which contains a lens or lenses and which I managed to unscrew. It is associated with the larger body with the bigger lenses, but for some reason is only visible with the eyepiece assembled. I am reluctant to try disassembling the eyepiece further without some hints or tips or some idea of what I am dealing with.
  11. That's entirely up to you. The bigger the scope, the heavier the subassemblies are, and the prospect of setting it up and taking it down at night becomes less appealing, and the bigger the bill when you fumble it and drop the OTA onto concrete. Personally I would not want anything bigger than an 8" in the CPC range, or a C9.25 if the OTA and mount will separate. Check the listed weights of these items, and if possible go see them in a showroom. Note that you need some way of holding onto a fat SCT OTA, and if working alone you need one hand to do up the clamps and one or two hands to hold it in place... Also note that these big expensive SCT outfits do not hold their new price well if you decide to sell them on, and you would be lucky to recover much more than half your initial outlay if you decide it's not for you. THe AZ-EQ6 should hold its value better.
  12. That would work, but you don't need an equatorial at all for solar system viewing and imaging. An alt-azimuth mount is much less bother. On the other hand, for a C11 the choices of alt-azimuth mount are limited... The AZ-EQ6 GT isn't a lightweight mount, but you would have the option of putting a cheap Newtonian or a refractor on it for widefield, or using it with an imaging scope at some point. You can get the C11 as a CPC1100 for solar system viewing and imaging, but that is even heavier than your first choice and best kept in an observatory (or on wheels). Personally, I'd suggest that you make a 'beginner' sized scope your first purchase, rather than jumping in with a costly, awkward to handle and more specialised setup. There is no rule that says you have to own just one scope, and your interests may change.
  13. Plenty of good advice above. Sadly, astronomy is not a cheap hobby, and the price of desirable kit escalates rapidly as one adds aperture and technical features. Many objects that look great in Hubble Space Telescope pictures can be underwhelming when viewed with a small telescope from one's backyard.
  14. Rather than trying to make the CPC925 (a very heavy instrument, BTW) into a widefield one, have you considered complementing it by buying a cheap, widefield, Dobsonian? It would cost little if any extra, and give you a grab'n go for the occasions when you don't feel like wrestling the CPC925 out of storage and spending half an hour erecting it.
  15. A dew shield should be considered an essential piece of kit on a SCT or Mak, just as it is on almost all refractors. Manufactureres don't like to fit them, no doubt because it makes their product look big and ugly. I have found a dew shield, either manufacturered or home-made, to be adequate on almust all occasions over several years, but in other locations results may vary.
  16. You should not need to re-align unless there is some slop in the connection between support arm and socket. I suggest you assume it's okay and see what happens. I find that my Starsense needs periodic re-alignment anyway.
  17. A flip mirror diagonal is a great help for imahing faint objects like Neptune. In Sharpcap you may find that the Histogram tool does not work and you have to set the exposure by trial and error. It is easy to over-expose the planet so that it burns out during processing. If you deliberately over-expose by a lot, you may capture one or two of the moons. I have my gain setting for this camera (ASI224MC) permanently at about 350. BTW, don't wait for the opposition date.
  18. For bright planets I use a GoTo mount to initially find the planet, then centre it in the eyepiece and then remove the eyepiece and fit the camera and acquire and focus the planet using the full camera pixels (e.g. 1304x976 px), and then reduce the field to e.g 320x244 to take video without wasting storage and slowing the frame rate. If I need to re-acquire the planet I use a 9x50 RACI finder and the full camera pixels. I don't think a red dot finder would be good enough as even the 9x50 barely gives enough magnification. I only use my flip mirror for faint objects, e.g Uranus, Neptune or plantary nebulae. Note that you need to use the ASI224MC with an IR-cut filter to get the correct colour balance. If you don't have a dew shield, you should buy or make one. A dew shield should be regarded as standard equipment on a Mak or SCT, just as on refractors. (The manufacturers don't want to provide one purely for marketing reasons - makes their product look long and ugly). I have not bothered with dew heaters as yet.
  19. I hope you find it useful. I got on fine with the Celestron instructions for their mounts (a multi-page A4 booklet). And the Nexstar system is easier to learn that the rival Sky-watcher. Do you have time to cancel and save yourself some money? The 2-star auto align is quicker and just as accurate, but you need to know your alignment stars.
  20. And get a dew shield. It should be standard equipment on a SCT, just as it is on almost all refractors. I have found that levelling the mount is not critical, except for one-star or solar system align. But you might be placing the mount on an uneven surface, and it's not hard to level, so why not check it?
  21. The sought object should appear somewhere within the field of the 25mm eyepiece. The tracking accuracy will be good enough to keep the object within the eyepiece field. You may see some movement initially as the drive takes up the slack in the gears. I would stress that the 6/8 SE mount is intended for visual use and is not good enough for astrophotography. The sole exception is that you can try it for planetary imaging, as the 'lucky imaging' scheme is tolerant of mount movement. It is difficult to align a wedge mount with the accuracy required for deep space imaging (and you don't need a wedge at all for anything else). The wedge is only really satisfactory in a permanent observatory (e.g under a 16" SCT). I don't think I need to underline how useless the SE/wedge combination is, even though some opinions may differ. The bubble level may cause some puzzlement. My kit was second -hand, but the bubble level is stored on the eyepiece tray and placed for use on the machined top of the tripod. A complication is that this requires you to separate the tripod and mount/OTA, which you may not want to do at all if you prefer to carry the OTA/mount/tripod outside as one lump. If you have a traditional (long) spirit level, you could try placing it across the eyepiece tray.
  22. Without the mount, it's a 127mm MAK and you can buy a 127 Mak (telescope only) from various suppliers. Often it's the same telescope from the same factory with different brandings. The Orion Starseeker IV looks essentially the same as the Celestron 127mm Mak SLT which I own, or the Skywatcher 127mm Mak Synscan sold in the UK. Then you need a manual mount, and you have various choices. It is less bother (and often cheaper) to buy the telescope and mount as a package, but if this does not suit your requirements there is no need to do so.
  23. I have been going through my collection of Plantary Nebula images, taken as the opportunities arose with two telescopes, a CPC800 8" f10 SCT and a 102mm f5 achronat, and a ASI224MC planetary camera. I wondered which was in fact the best tool for the job, as some planetary nebulae are very small. In general the SCT images have blurred stars (if they have any stars at all) while the 102mm images have a wider field, generally include some stars which look sharper, and since there are stars in the image I can usually attempt a live-stack. I have not checked exhaustively, but the exposures should be shorter with the f5. In short it looks like the 102mm f5 is the better tool for the job, and a better match of seconds of arc vs pixels. I intend to continue the Planetary Nebula imaging, concentrating on the use of the small refractor. I wonder if the OP bought the big Meade?
  24. Very odd. I still don't see why the finder should move that much. That amount of play should be obvious if you handle it. If you attach a second finder (so two finders are attached) even temporarily, you should find out where the problem lies. It wasn't in the field of a low power eyepiece after the meridian flip? Was the finder cross hair on Jupiter after the meridian flip?
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