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mikeDnight

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About mikeDnight

  • Rank
    Brown Dwarf
  • Birthday 04/02/1962

Profile Information

  • Gender
    Male
  • Interests
    Lunar & planetary , binary stars & comets.
    Visual astronomy in general and an advocate of sketching as an aid to observing.
    I also have a passion for refractors and optics in general, and have a deep interest in the history of amateur astronomy, the astronomers and their scopes and observatories.
  • Location
    East Lanc's
  1. Some mass produced low cost refractors from China can suffer from spherical aberration which can play havoc with the image quality. By reducing the aperture you may be using the better figured central region of the lens.
  2. M65 + M66

    Beautiful sketch!
  3. Domes around Arago

    The terminator was spectacular this evening, and from a sketching point of view just a little terrifying! After scouting around for half an hour or so, I came across a simple looking crater named Arago, which caught my eye due to two nice domes close by.
  4. Thomas Bopp

    The sad news this morning was that Thomas Bopp, the co discoverer of comet Hale Bopp, has passed away age 68. His comet was so spectacular that it will be emblazoned in our minds and hearts for ever!
  5. What scopes are these?

    Looking at the cell castings, the Maksutov looks very much like an old Photon Optics.
  6. M78 is a binocular object, though it will be better seen in a telescope! I've seen both M78 many times and NGC 2024 a couple of times in my 4" refractor. NGC 2024 is a major pig to observe visually in a small scope due to the brilliance of Alnitak. If you can keep Alnitak out of the field of view, you will stand a far better chance of detecting it in your scope. The nebula itself is quite large and I'm sure I've read somewhere that an Hydrogen beta filter aids in its detection. Both the sketches below were made using a 100mm refractor. Below The Flame Nebula.
  7. Saturn in the mornings?

    I took a look at Saturn this morning (20th Feb) but the view of it was probably the worst I've ever had. Also Jupiter, despite being much higher, was almost featureless with only hints of the belts being seen. Yet tiny Mars, which wasn't much higher than Saturn, did eventually offer up some subtle detail. We are definitely suffering from a prolonged spell of poor seeing as far as the planet's are concerned!
  8. MARS at 6.3 arc seconds

    Thanks chaps! It shouldn't be too long before the increasing image scale will make things much easier to see. Although the low angle will make observing it a challenge!
  9. My TAKAHASHI SEISAKUSHO, instrument album.

    SIGH! 💔 Rather stupidly I sold my extender Q, and immediately regretted doing so! Rather than continually screwing it on and off I should have just left it on. It was beautiful! 😭😭😭 I've definitely got to get another one!!
  10. MARS at 6.3 arc seconds

    It's definitely getting bigger but its still a tricky little tease. This morning's sketch was made under less than ideal conditions, as the image suffered from some turbulence due to its low angle. On top of that there was incoming cloud that kept dimming the view. Still, after twenty to thirty minutes scouring the tiny disc for every trace of potential detail, I ended up with this pleasing result. LCM = 196.99°; D = 6.3 " arc; Tilt +3°. Magnification X197; Takahashi FC100DC with prism diagonal. Seeing =lll Antoniadi. Below in classic orientation!
  11. F10 apo's?

    If someone is looking for a long focal length apo, they could do far worse than the Takahashi FC100DL at F9. If its absolutely necessary to go longer, then one of the FC100DC or DF F7.4 with the amazing Tak 1.6X extender Q attached will give you an optically perfect F11.8. Or if you're really bent on long FL, then the FC100DL with Tak 1.6X extender Q will give you F14.4. If larger aperture is needed then the Takahashi TSA or TOA, or an older FS 128 or 152 with their respective extender Q's attached will do the job perfectly.
  12. F10 apo's?

    I'm trying to tame my comments, so I'll say I'm so glad you didn't fall for the Cape Newise Stu. Two of the things were on loan to my local astronomy club and the optics were just monstrous!
  13. Coma at F6 will be less than that at F5, and the longer you go the closer to spherical the optics become and the better the performance, in theory! Harold Hill used a 10" F10 Newtonian, but in his book A Portfolio Of Lunar Drawings, he mentions that the same detail seen in his 10" is also visible in his old 6.25", though its brighter and easier to see in the 10". Perhaps the subtle differences between the F5 and F6 would be more to do with the less critical focus and higher power per given eyepiece in the F6 vs the easier to mount, less cumbersome build of the F5. An experience that I and another astronomer had a few years ago might be worthy of consideration. I had an SW 200mm F6 and a 120mm SW ED set up in my garden. Both were set up at 3pm but it wasn't until 9pm that we actually decided to do some observing, so both scopes were fully thermally stable. Looking at the Moon through the 8" was just breathtaking, and a more perfect image was almost impossible to imagine. Yet, on moving to the 120ED, the level of sharpness was in a whole different league. We were both stunned by what we saw and spent some time carefully examining the more intricate lunar features in both scopes. Our conclusion was that, although the 8" was obviously brighter, any resolution advantage offered the the 8" was lost in its softer image. Incidentally the seeing was excellent at Antoniadi 1! Our next target was Saturn, which was high in the SE. Here is where we both felt the better resolution of the 8" would become obvious. Again we were both stunned by what we saw! The 8" did indeed give a view of Saturn that was apparently perfect, until we looked through the ED. The 120ED, though less bright, revealed with ease, intricate detail in Saturn's rings that simple wasn't there in the 8" no matter how hard we looked. So we concluded that the only advantage the 8" had over the 4.75" ED was its light gathering capability. Obviously then, if DSO's were our preference, then the 8" would be a more suitable instrument and at F6 it would show marginally better correction at the edge of the field than at F5.
  14. Little and large

    Very nice set-up Gavin, but I see that even you've had to make sacrifices along the way!
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