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Luna-tic

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Everything posted by Luna-tic

  1. Well.......if you put it that way, I can image/view at 478mm, 945mm (effective), 1400mm (effective), 1500mm and 2000mm. I'm just thinking of all the different fields of view I'll have at prime focus. This one will be the LAST. Period. No more. I swear. Now it will be guiders, CCD cameras, processing programs, laptops.....
  2. Now all I need is a three-headed coin to help me decide which one to use on a given night. I love my SCT's, but I'm worried it might become a menage a trois in the meadow on clear nights.
  3. Already spent my Christmas money, and then some. Ordered a William Optics GT81 APO triplet f/5.9 with field flattener/reducer that makes it f/4.7. It has a 2" 1:10 Crayford 2-speed focuser. Now, I'll be able to image at f/4.7, f/5.9, f/6.3, f/7, and f/10, depending on what I want to shoot at.
  4. One of the surgeons I work with grew up on the "Space Coast", in Port St. John. It's about 13 miles from Pad 39A, where both the Saturn V and the Shuttle launched. He got ringside seats, so to speak, for all the Apollo and the earlier Shuttle launches. He said in conversation at work one day that although the Shuttle was a spectacular launch due to all the smoke from the SRB's, it was nothing compared to the Saturn V. He also witnessed the Challenger explosion.
  5. Seems a waste to ditch a perfectly good finder scope in order to replace it with essentially the same thing, that has ability to mount a camera to. Is there a way to modify a 9x50 finder scope into a guide scope?. I'm speaking specifically about the 9x50 that comes on the Edge series SCT's. Thing is, I don't even use it for it's intended purpose, I find my Quickfinder more useful for that and don't even mount the finder scope any more when I go out. The EP of the finder is smaller than what's needed (less than 1.25"), can it be removed and an EP holder cobbled onto the body? I suppose focusing it would be part of the problem, too.
  6. I was a month shy of 15 when Neil stepped off the LEM's foot and said his famous line. I had a 3-foot model of the Saturn V, all the stages separated, the clamshells on the S-IVB opened and the CSM would dock with the LEM. I followed every stage of the flight with that model, sitting in front of the TV and watching it. No matter to me whether any of the coverage was in color; we had a black and white TV until I was 17. We didn't lose anyone IN space during our manned space program, but came pretty close with Apollo XIII. Sadly, we did lose several in other circumstances during the program. The most notable being Gus Grissom, Roger Chaffee and Ed White in the 1967 Apollo I fire, but there were eight other astronauts or astronaut candidates killed in the period from 1964 to 1967, mostly in aircraft incidents either directly or indirectly involving their training. Who can say what their contributions might have been? And then there are the two Shuttle crews in the years since Apollo. I didn't follow the Shuttle program quite as avidly as our earlier space programs, but I can tell you exactly what I was doing when the news reports broke on the Challenger launch explosion, and then 17 years later when the Columbia broke up during re-entry. One of the saddest aspects of the whole thing is, that we haven't been back to the Moon in 45 years. Was all that effort to get there a serious attempt at discovery, or just a stunt to beat the Russians? It's almost poetic, that now we have to beg a ride from those Russians, just to get to the ISS and back. Don't get me wrong, I hold nothing but admiration for their program; it's had its share of grief and victory as well, but they've never thrown away technology, just built on it.
  7. Our Moon is the largest in the solar system relative to the size of its planet, but the 5th largest overall. Only Io is more dense than our Moon, of all the planetary satellites. At some time in the not terribly distant future ( none of us will be around, though) total solar eclipses will all become annular; the Moon's distance from Earth is gradually increasing.
  8. Oh, but of course, they want you to spend another couple hundred $$ for the adapters. They have a chart showing all the combinations of adapter with what they will adapt to the EP, so I suppose it does make it more versatile that way. Most of my EP use is at f/10, with occasional jaunts to f/7 or f/6.3 if I'm using the focal reducers for the respective scope, so they should be acceptable for my needs, unless and until I get the f/5.9 frac my heart desires for widefield work.
  9. The reason we see 59% of the portion of the Moon that faces Earth is due to its own axis of rotation relative to its orbital plane and the Earth's orbital plane, called libration. The Lunar far side gets just as much light as the near side, due to its rotation relative to the Sun. The Moon's orbit is tilted 5.145 degrees relative to the Earth's orbit around the Sun, and this tilt "rotates" once every 18.6 years. This is the reason we have periodic series of lunar eclipses rather than continuous lunar eclipses. The plane of Lunar orbit has to coincide with crossing the ecliptic at the New Moon in order to have a solar eclipse, and has to coincide with crossing the ecliptic at Full Moon to have a lunar eclipse. To illustrate this, Google the solar eclipse maps that were all over the 'net during the total eclipse last August in the US. This past eclipse was a "descending node" eclipse, the land track was from northwest to southeast. the next US total eclipse in 2024 will be an "ascending node" eclipse, travelling from southwest to northeast. If you look at any of the past or future eclipse tracks, they will follow one of these general paths at some point on the Earth's surface. Solar eclipses are easier to demonstrate because of the much smaller umbra than a lunar eclipse has. The orbit of the Moon is fairly complex, it's much more than a circle around the Earth. Due to this orbital angle relative to the ecliptic, the Moon will also appear higher or lower in the sky from time to time in its apparent track across the night sky. Additionally, the difference in the Moon's period relative to the Earth's rotation means it rises each night about 50 minutes later than the night before. Add to this a natural "wobble" in the Earth's rotation and in the moon's rotation, their inclination to each other in rotation and their individual orbits around the Sun, it gets pretty complicated. If you could look down from "solar north" at the Earth's orbit around the Sun, and the Moon's orbit around the Earth, it would appear that the Moon was moving in and out between Earth and Sun as the Earth orbited the Sun.
  10. The one I use will power my mount and two dew heaters at 3/4 power for 6 hours or more with no issues. The cigarette lighter outlet is wired direct to the battery; the jumper cables go through a circuit with a high-discharge capacitor to ramp up the current for jumpstarting, the battery by itself can't supply that much current that fast. If those cigarette jacks, plugs, whatever, are so bad, why do most makers of dew heater controllers and mount drives use them?. For DC voltage at the current levels we use, they work fine.
  11. What I'm asking about are the M43 thread and the M54 thread at the top. What is designed to screw on there? The M43 isn't the same as the T-ring thread my Nikon ring has. My T-ring fits just fine on the threads at the top of my Ultima Duo EP. Late edit: went to the Agena Astro site; there are a series of adapter rings to allow the connection of anything from a T-ring for a DSLR, to extension tubes, to DSLR lenses to ccd cameras. You pick what you need. I ordered a M43 to T-2 adapter, so I can attach my DSLR for EPP.
  12. I got the EP (8mm) today; boy, it's a big honker. Actually, the same size as the 13mm Ultima Duo EP I have, has the same 68* AFOV. Looks well made, if it doesn't work as an eyepiece I could always bludgeon somebody with it, I suppose. I'm curious about the two threaded rings around the ocular, what is supposed to fit on them? The smaller ring, closest to the ocular, is just the tiniest bit too large in diameter to thread my Nikon T-ring on; the larger threaded ring, about 10mm lower, is much larger diameter (same as the body of the EP). The literature said that camera adapters could thread directly to the EP, so I assumed my T-ring would fit, but it doesn't. Is there a special Baader (or Orion) adapter that those threads fit? It's not a terribly big deal, but part of the reason I bought this EP was for the possibility of using it for EPP. I'm also going to e-mail Agena Astro, where I bought it, and ask them.
  13. Wonder if the Orion Straus is any less expensive, will have to check them out. These will be used in a C6 and Edge 8", so from f/6.3 to f/7 to f/10
  14. The others are good, but this is fantastic!. Sold me on getting an 80 of some sort.
  15. What's everyone's take on these EP's? I read pretty good reviews, but since some come from the advertising end, there could be bias. I like that the focal length can be changed, and I also like that a T-ring can be directly installed for EPP use. Price point is pretty good, too.
  16. I suppose what they say about these nebulosities being the birthplaces of stars, etc. is true. This reminds me of photos in anatomy texts that show sperm trying to penetrate an ovum to fertilize it. Life on a grand scale.......
  17. Can't imagine what you could do better, that's beautiful.
  18. Fantastic image, well done considering the difficulties. Can't wait to see the final result after you've played more with it.
  19. Polaris would have been a good one to find, as it is a double star that can be easily split at low power, but not visually seen as a double. Those are the ones to look for, (double stars) they will hold more interest than a single point of light that really doesn't look any different through a telescope. Mizar/Alcor is another one, they're the second stars in the Big Dipper's handle. Good eyes can detect the pair, but low power in a telescope makes it much easier for older eyes. Try to find Albireo, The "eye" of Cygnus, the Swan. It is a different-color pair, one star is smaller and bluish-green, the other is larger and orange. Castor and Pollux (Gemini) are both double stars, although Pollux needs a LOT of magnification to split, Castor is fairly easily split at 90-100X. Other easily found objects to look at would be the Pleiades in Taurus, and M42, the Orion Nebula, which easily shows up with binoculars and at about 60-80X you can split the 4-star cluster at its center, called the Trapezium.
  20. What are the specifics on the picture? Shutter speed(exposure time), ISO? It's not a bad early effort, you can see the graininess and "noise" from what is maybe a high ISO (>6400). I made some shots of M42 as my first AP attempts, since it is such a bright DSO. I used ISO 3200 and about 21 seconds, as well as 6400 and 26 seconds, to see what the combinations of exposure times and ISO did to the image. This is what I got, very similar to yours. Keep playing with combinations of ISO and exposure time. On a single exposure, with good tracking, about 25 seconds is all you can hope for before the stars begin to move. Don't know how to eliminate a duplicate post, I hit the save button twice.
  21. What are the specifics on the picture? Shutter speed(exposure time), ISO? It's not a bad early effort, you can see the graininess and "noise" from what is maybe a high ISO (>6400). I made some shots of M42 as my first AP attempts, since it is such a bright DSO. I used ISO 3200 and about 21 seconds, as well as 6400 and 26 seconds, to see what the combinations of exposure times and ISO did to the image. This is what I got, very similar to yours. Keep playing with combinations of ISO and exposure time. On a single exposure, with good tracking, about 25 seconds is all you can hope for before the stars begin to move.
  22. Pretty close, I think, except your eye will give a much wider FOV with peripheral vision, but your central vision would be close to what a 50mm lens gives. I think that is why 50mm is so commonly used for standard prime lenses. Not sure if that was directed at me(with all the quotes flying around), but my D3400 Nikon has a crop sensor.
  23. I should add, your go-to alignment needs to be fairly precise when searching for some of these DSO's. Some are faint enough visually that you will barely see them, and unless they are in the FOV when you tell the go-to to skew to it, you may not find it. Your FOV is pretty narrow at f/10, use a low-power EP when searching (I use a 25mm Plossl a lot), or something with a wide FOV. On occasion, I couldn't see the object at all, but when I took a quick 15-20 second exposure, it was actually there.
  24. You can see the Crab through your 8SE on even a moderate 'seeing' night, but visually it will never be more than a smudge against the blackness. Same as with other DSO's like M31 or M13 or M2. It takes a camera, that can collect the photons, to bring out the image that our eyes cannot see the full extent of. These pictures below were all made with an Edge HD 800, basically the same telescope as your 8SE. These are all around 30 seconds' worth each of collected photons (single images), to see them well enough to discern their shape and some detail. The Crab (M1) is dimmer than many and takes a bit of work to bring any color out of it, along with a much longer than 30 second exposure. Just be happy knowing you're looking back in time when you visualize any of them, however poorly. Lots of things will affect how well you can visualize them, as stated before. Light pollution, clarity of the sky, etc. 1-M1, Crab Nebula 2-M31 Andromeda Galaxy 3-M2 Cluster in Aquarius 4-M57 Ring Nebula
  25. Shouldn't it say, Bellatrix rises, followed by the whole of Orion? Bellatrix rises 27 minutes before Betelgeuse, at least in my back yard (35.5 degrees North). Of course, Tabit clears the trees 34 minutes before Bellatrix does. Not that it really matters, though. Orion is my personal favorite part of the sky, from NGC2175 to Rigel. When I see Aldebaran above the ground clutter, I get my gear ready.
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