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hrgreen

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About hrgreen

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    Nebula

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    Cocoa FL

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  1. It IS quick and easy to set up my basic scope. The construction is light enough that at 78, I am able to lift the Rocker Box and VMB with (full thickness) mirror into and out of my car, and mounting the struts/front ring takes only a few minutes. There is no doubt about where anything goes, and no adjustments to make except minor collimation. Installing all the accessories does take some time. A club member has a standard 18" Obsession and sets it up alone, but he carries the mirror separately. I'm not willing to handle the mirror, and I prefer to uncover it only after everything el
  2. Rob, I got the Nexus WiFi rather than getting a WiFi for the AN, so no. Read the CN and AF discussions on the Nexus; many prefer it. Hal
  3. A few additional notes I found it easiest to keep the VMB and Rocker Box together when moving the scope in and out of the car, although the rubber band method will allow me to re-assemble them alone. A little more weight to handle, but OK. I changed cars to the even smaller Prius C, which has almost no room behind the back seat, and found I could load everything after the seat folded down. I obtained a Nexus DSC/WiFi to use in place of the Argo Navis. I do like it better; got tired of spinning that AN dial and filling out names. It links to SkySafari 5 in my I-pad. The display i
  4. My installation of the ServoCat Jr. drive system went well. StellarCat doesn't have a template or good photo for mounting the ALT motor on a 15 UC, but I was able to figure it out. I also realized that there is a disadvantage to the ServoCat. Normally, a person working alone would want the (Virtual) Mirror Box and Rocker Box to be separated for transportation, because together the weight is kinda high. But putting them back together is complicated by having to thread a cable the length of the lower ALT bearing while assembling, seemingly impossible for one person. I found someone has figured o
  5. Thanks again for your replies. I don't have a good picture of the scope, maybe later, but there are some on the Obsession website. Faulksy, I have a Paracorr II, but have not tried it yet. Things have been looking pretty good without it, although I haven't looked closely for coma yet. Besides Televue EP's, I have ES 4.7, 8.8 and 14 mm 82 degree. These seem quite good. I want to compare the 8.8 to my 9 mm Nagler when I get a chance. The ES were bargains at the introductory prices, about $80, and I plan to keep them for public star parties. Hal
  6. One thing I didn't mention that makes setting up the scope easy is using Howie Glatter's 2" collimator and Tublug. These allow aligning the primary while providing a Barlowed target image easily seen from that end, without removing the shroud. They are very well made and make short, foolproof work of the job. I also have a crosshatch accessory that shows exactly the centering of the secondary. I highly recommend these. Hal
  7. Though I have had this scope for some weeks, there hasn't been a break in cloud cover until last mid-week here in east central Florida. Finally got first light. Dobs are new to me, so much to learn. The scope is mechanically an ideal compromise for me, as the Virtual Mirror Box is within my safe limit to lift (45 pounds) in and out of my small car. The ALT upper bearing is hinged, and can be folded, then the ring can sit on top, making a package that can fit into just about any trunk or boot. Also, being an f4.2, it doesn't require me to use a stepstool. Its truss design is made with
  8. (Not being an optical engineer, I apologize if I have any of these details wrong, as I'm trying to quote info from the Zambuto site) The best measurement of the quality of a mirror is thought by many experts to be the Strehl ratio. A perfect mirror would contain 83% of the light from a point source within the first difraction ring. The Strehl ratio is the percentage (usually given as a fraction) of that 83% that a real mirror is measured to contain. An excellent mirror would have a ratio of 0.97-0.99, a very good mirror 0.94-0.97, and so on, down to a so-called "diffraction limited" mirror
  9. Two questions I have after reading all posts I could find. 1. The plate glass sandwich mirror is reported as unusually messy during cooling, and not as quick to stabilize as HO says. Do you find this? Have you had a chance to do star tests? People who do refiguring seem skeptical about them. Wonder if a Pyrex would be worth the higher cost. 2. Has HO listened to and corrected the mechanical problems reported? In particular, have they made the GOTO easier to install? How well is yours now working? Wanting an easily transported scope, I'd buy an Obsession 15 UC, but just too expensive, sa
  10. Received a CEM60EC three days ago. Weather not great, so I'm testing what I can inside. There is a new upgrade set on the website (529 I believe) for all four boards, and I had no trouble upgrading. Looks great so far, smooth and free of backlash. Hal
  11. Last month, I had my 925 CGEM working with a StarSense driven by a SkySync GPS. But on the 9th of this month, I got an Auto Align and stars were about right, but Jupiter was way off. I checked the GPS clock data, and everything was right except the year = 2012. Reboots didn't help. Switching to the RTC seemed to fix things. I sent a message to TeamCelestron, and found they know about a bug, but don't have a fix yet. FYI. Hal
  12. Wanting a better focuser for my CGEM 9.25 Edge, I had to consider whether using an eyepiece focuser would extend the back focus too much. The Edge 9.25/11/14 models are specd as having the best sensor image at 5.75" (146 mm) from the large adapter nut. Although visual is not as critical, I was getting very sharp stars out almost to the edge of the FOV with a Nagler 31 and a Panoptic 35 without a focuser, and didn't want to see coma, spherical and aperture reduction because of inserting one. The techies say that adding X amount of back focus is like adding 3X amount of focal length. I tried a
  13. I had problems with the SSA at first on my CGEM 9.25 because the Calibrate Center operation is not correctly detailed in the manual, and I managed to get the center set out of range (either number over about 1000). When I got that straight, I was getting offsets up to 2 degrees every time I removed and replaced the camera in the dark, where I couldn't see well enough what was happening. This proved to be because the camera dovetail had metal spurs sticking out of the screw holes and interfering with consistent mounting. Some filing and sanding fixed that. Friday night, I went to a star party
  14. I've been using an SSA on my CGEM 925 Edge for about 6 weeks, and am now getting good results. It looks for plate matches in four blocks of the sky, and if any rejects, it is usually smart enough to try a substitute. No need to do more than a rough polar alignment, and takes only about three minutes. There were two problems I ran into. One was when calibrating the camera to match the OTA, it is possible to accidentally set its logical center outside the sensor, killing Aligns. The clue is in the cal numbers, which should be less than 1000 or so. This can only be fixed by a new Calibrate C
  15. What a great number of welcomes! Thank you all. Dana, I'm not a baseball fan. But Red Dwarf, two particular things impel me toward Spain. One is a love of Flamenco; I studied guitar with a very good player in D. C. before having to leave for Florida in '62. The other is your modern high-speed train system, as I am a model and prototype train nut. Proto Star, I'm also very interested in the "boats". My family was mostly Navy, and I had an uncle on the Squalus in1939. When the Nathaniel Greene (sp?) came to the port for missile tests, we traded the crew launch pad tours for a tour of th
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