Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

  • Announcements


Geoff Lister

Advanced Members
  • Content count

  • Joined

  • Last visited

Community Reputation

233 Excellent

About Geoff Lister

Profile Information

  • Gender
  • Interests
    Railways (full-size and model), radio-controlled model boats, and astronomy
  • Location
    North Somerset, UK
  1. If you have a PC, download a copy of the "Stellarium" planetarium program and, in the "Location" window you will find 'Nelson NZ' to set as your default location. This is useful to use during the day, to plan your next evening's observing session. Geoff
  2. Recommend a Portable Scope

    Given that the AZ GTI mount manual shows the extended height as 1100mm (110cm), and the lower leg sections fit inside the upper sections, it is unlikely that it will fit, even diagonally, in a 55 x 40 x 25 cm bag. I measured the tripod supplied with my Skymax mount, and it is 68cm long fully collapsed. You will need the Ryanair/EasyJet (other budget airlines are available) greatcoat with deep poacher's pockets. I have a multi-pocketed gillet for air travel, but the pockets are not deep enough for a tripod. The budget airlines' check-in queues often have people wearing strange clothing (I've been behind someone in a fluffy dressing gown) to stay within the cabin baggage size or weight restrictions. However, the manual also indicates that the mount's head will fit on a photographic tripod, fitted with a 3/8" - 16 UNC male thread. It may be possible to get a smaller camera tripod + 1/4" - 20 UNC female to 3/8" - 16 UNC male adaptor sleeve (I got a couple on EBay to tripod-mount my Virtuoso Dob base). Geoff
  3. Recommend a Portable Scope

    Skymax - NO, AZ-GTI - YES
  4. Power Cable

    Sound advice for any lead-acid battery. I have one of these jumper packs, and I have its plug-top power supply permanently plugged into a timer, so that it tops up for about 30 minutes a day. If my car has been unused for a couple of weeks, I connect the jumper pack across the battery, and its power supply also acts as a trickle charger, replacing the charge lost by powering up the car's security devices - so keeping both topped up at the same time. Geoff
  5. The Skywatcher Synscan system has a similar feature; you just have to enter the correct date and time after power-up. I used Stellarium, and by altering the date and time, I produced a table with an entry for the middle of each month of the year, and 14 of the brightest stars. For each month, I have identified 3, 4, or 5 of these stars, their rough direction (N, NW, W etc.) and their altitude angle, at dusk, and a similar table for an hour before dawn. This way, I can avoid any handset-suggested stars behind fences, roofs or trees, or any too close to the zenith or horizon. Geoff
  6. Recommend a Portable Scope

    I agree with those above, for portability, it is hard to beat the 127mm Mak, on an Az/Alt mount. Many years ago, I bought the Celestron Astromaster 130EQ-MD, on its EQ mount, and found it difficult to set up, and get the motor drive to track. So I went for the Skywatcher Skymax 127, with the Synscan GoTo. I liked it so much that I got a second one to take to my holiday home in France. The OTA is really solid, and I have not had to touch the collimation in either. The whole kit is portable, the photo below gives you an idea, and the whole lot, with a couple of sets of batteries, and a few eyepieces is under 11kg. This setup gets more use than the rest combined. The AZ-GTI mount is a more recent addition, and introduces releasable clutches so that you can use it unpowered. I prefer the real buttons of a handset, rather than the virtual ones on the touch-screen of a tablet or phone. Geoff
  7. I made a small adaptor so that I can use my Virtuoso mount on my Skymax's tripod. I screwed a "Terry" clip to the side of the Virtuoso mount, to keep the adaptor handy.
  8. I have the Starsense camera and system built into my Skyprodigy mount as part of the original design. It needs reasonably dark sky to get enough stars in the image, so that it can plate-solve and work out where it is looking. If I can see lots of stars, so can the camera, but if I start the alignment process before adequate darkness, it gets confused, has several tries, then gives up, requiring a power cycle to start again. I got the Skyprodigy 70, for under £200, as the cheapest way to buy the Starsense, and have a spare mount for my other OTAs (after a slight modification to the plastic cowl over the dovetail clamp). There have been a couple of occasions when it announced that it was aligned, but GoTo was tens of degrees off, but a restart sorted it out. There are menu options to compensate for light pollution, including a full Moon, but I find the "standard" settings work for me. On an average evening, I can do a "Brightest Star" 2-star alignment on my equivalent Skywatcher Skymax mount with the Synscan system, probably 45 minutes earlier than with the Starsense, as the brightest stars (Capella, Sirius, Arcturus & Vega) are visible close to sunset. I only need to spot 1 star, because the Synscan system does an automatic slew to the second star, and it usually places it in the field of view of the finder, and often in my 32mm eyepiece. However, I still have to wait the 45 minutes before I can start observing, so no real gain, and plenty of time for the British weather to change from clear skies to 100% cloud. Geoff
  9. Yes, mine does too. My Virtuoso mount has a female 3/8" - 16 UNC tripod thread, but most of my photographic tripods (cameras and dovetail bars) use 1/4" - 20 UNC. A quick web search indicates that the Star Adventurer wedge seems to have a 3/8" female thread on the tripod end, but I could not find thread details for the male, camera/OTA, end. Geoff
  10. If your 'scope came with a blanking/dust cap protecting the eyepiece holder, a 1mm hole drilled in its centre makes a very simple collimation cap.
  11. Power Cable

    The manual for your mount states a power supply of 11V @ 3A to 16V @ 2A, so the Halfords jump starter pack should be fine. Geoff
  12. I have 3 versions of the manual, 2 PDFs downloaded about a year ago, and the paper version supplied with my 'scope. Each is different. My paper version "Instruction Manual MiniDob Mount" has the cover sheet and then internal pages labelled "1" to "16" + back sheet. One PDF, 7656KB, with front page title "Instruction Manual Skywatcher Virtuoso Multi-purpose Mount #S11750" seems to be aimed at the USA market, has an additional solar filter accessory, and a Celestron USA contact address; it has 13 pages. The other PDF, 368KB, same title as my paper version, but with different text, graphics and paragraph structure, and with front sheet, then pages labelled "1" to "10" (no back sheet). My paper copy, on page 11, has the following section entitled "Equatorial Tracking Mode for Celestial Body" 1. Attach the MiniDOB onto an elevation degree adjustable tripod according to the figure below:- (figure shows a tripod with an adjustable inclined plane) 2. Users in Northern Hemisphere aim the tripod at North (Users in Southern Hemisphere aim the tripod at South). Adjust the elevation angle and ensure it equals the local geographical latitude value. (No advice for those living on the equator). 3. Set the Latitude setting for the MiniDOB according to the 'Quick Guide' (pg 3). This is a bit confusing, as there is no 'Quick Guide' on page 3, but pages 1 & 2 have a 'Quick guide' for North and South hemispheres, respectively, and section 3 of each shows setting local latitude for N hemisphere and "0" for S hemisphere. 4. Press '5' first then 'turn on power', it should now be under the RA equatorial longitude tracking mode. I assume that, in stage 4, holding down button "5" at power-up, turns off the altitude axis tracking component. Worth a try at some point. Geoff
  13. The virtuoso mount uses the standard Celestron/Skywatcher/Vixen dovetail clamp. The basic mechanics are designed around a light-weight, compact, OTA. I have used mine with my 127mm Mak (3.5kg instead of the 90mm @ under 2kg), and the OTA from my truss-tubed 130mm Newtonian Heritage 130P, but I try to avoid doing maximum-speed slews. The Virtuoso mount has adequate clearance for the 90mm OTA, but will not work with a balanced 127mm or 130mm at high altitude angles. A long-tube refractor would also have similar restrictions, and would impose greater torsion loads during acceleration. Like many pieces of equipment, you only know the true limits when something breaks . Geoff
  14. I am not familiar with the Nexstar setup, but Doug's suggestions, above, seem reasonable. I used "align a celestron 130 slt nexstar" in Google, and there seems to be plenty of additional advice including videos. Geoff
  15. The Virtuoso's Dob mount is fitted with 1 medium-length foot and 2 shorter feet with screw threads. These have enough adjustment to get the bubble level centred on a table sitting on a slightly sloping patio. With my Skyliner, the 3 feet are fixed. I fitted a 35mm diameter bubble level to the rotating section of the base. When I place the base on the patio, I lift and rotate the whole assembly, until the bubble is opposite one of the feet. I then slip a "Fox Wedge" under that foot, and push it in until the bubble is central. I then fit the OTA, with it pointing roughly north (hiking compass), and level (altitude scale on mount), then power up. I have found that, by doing this, I get the most accurate GoTo and long-duration tracking. Geoff