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Piero

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Piero last won the day on June 6

Piero had the most liked content!

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About Piero

  • Rank
    Brown Dwarf

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  • Website URL
    https://uk.linkedin.com/in/pdallepezze

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  • Interests
    Amateur astronomy, bioinformatics, software engineering, mathematics, languages.
  • Location
    Cambridge, UK
  1. ^^^^ very true! And yours (Chris) is also an excellent light setup!
  2. I also prefer the 24 Pan to the ES_82 or Vixen LVW I bought, in terms of FOV performance and at the edge.
  3. I mean that the 24 Pan shows a lot of rectilinear distortion (RD). TeleVue consciously introduced it in order to control astigmatism and angular magnification distortion (AMD) at the edge within a certain threshold (which I believe is 1%). RD does not cause issues when observing a large star field, and one can notice it when spanning along the Milky Way (pincushion distortion) or when large targets (e.g. Moon, Sun) are moved near the edge (they appear like ovals). Personally, and by some criticised, my preference for eyepieces is: - a trade-off between RD and AMD (the two are inversely proportional); - zero astigmatism. The Docter UWA is an example of these kind of eyepieces. There is this long-lived belief that terrestrial eyepieces should minimise RD, whereas astronomical eyepieces should minimise AMD. Essentially, this is what TeleVue has done. To me this is down to one's preference and not something biblical. I prefer to see the moon as a sphere near the edge rather than an oval; whereas others prefer to see the separation between 2 stars to be constant within the field of view. One cannot have both for reasons concerning optical physics, but I just don't see anything wrong with having some AMD in an eyepiece used for astronomical purposes. Just my 2 pennies. p.s. hope this does not start an AMD vs RD war, with an army waving TV flags!
  4. The 24 Pan is a good eyepiece but with a lot of RD. With the TV60, it works well when observing a large open cluster. Due to RD, planetary targets look like ovals at the edge. At 15x this is not really an issue, though - apart from poetic observations of the Moon / Sun coming up from the surrounding trees.
  5. When I saw the first photo I thought the blue in the telescope and tripod is a nice match! Anyway, as long as it works well, colours are secondary.
  6. I agree about the TS head. It's a nice and light mount. Great equipment BTW. I thought about the Neewer carbon fiber tripod for a while, but eventually got the Manfrotto, as you know. Looking forward to reading your thoughts about it.
  7. Great report Jeremy. I've always used a 24 Pan as wide field eyepiece with my TV60, although I'm considering a Plossl 32mm as addition or replacement. You could also consider the new 24mm APM ultra flat field.
  8. Piero

    Superb Jupiter!

    Cheers Jeremy Looking forward to reading your report!
  9. Piero

    Superb Jupiter!

    Thanks John. Those sky conditions were completely unexpected. No air turbulence at all.
  10. Piero

    Superb Jupiter!

    Considering the rather strong wind blowing all day, I was really surprised to see a steady sky this evening. Therefore, I decided to take the telescopes out to observe Jupiter. The TV60 was coupled with the Vixen HR 3.4mm, whereas the Tak 100 with the Zeiss zoom + VIP barlow. Surprise surprise, I achieved some very fine views with both these scopes. The GRS was so obvious in the TV60 that I had to detach from and go back to the eyepiece a couple of times to make sure it was not a fantasy. I do not have a memory of such a detail in that scope, TBH. It generally appears a bit fuzzy and requires some effort, whereas tonight it was a clear and distinct brown oval. Faint details on the equatorial belts were also detectable with some patience. These appeared like minor irregularities in the shape and colour of the lines forming the belts. The polar regions were also softly depicted. Once I moved to the Tak100, all those faint details became obvious, whereas a multitude of other features emerged. A complex and elongated white-ish feature was visible on the north equatorial belt, opposite to the GRS. The sky was so steady that I could increase the magnification at about 240-250x. At this level, the thick brown GRS showed its own internal details. These were not easy to spot, but were essentially made of darker curves, kind of concentric ovals separated by a darker brown colour. The hollow of the GRS was also rather easy to see. A minor "belt" was right in between the two equatorial belts. Then there were the north and south temperate belts. Finally, the polar regions. Each of these belts presented zigzag patterns. The four Jovian moons appeared like mini disks above 180x-200x. These were perfectly defined even at the top zoom end (276.1x), revealing no glare or light scattering. The session completed with a more relaxed observation with the Docter + VIP at about 150x. Another terrific sight..!
  11. Piero

    Do I need another eyepiece

    A 18mm would fit in there no doubt. Said this, I like some gap at lower focal lengths. A 20mm 100 Deg would solve the issue and even remove the 26mm Nagler, but you moved to the opposite direction, which suggests different tastes.
  12. Piero

    What did the postman bring?

    I must admit that I have recurrent thoughts about replacing my 24 Pan with a 32 Plossl for similar reasons. 32mm is also more distant from 21mm (the longest f.l. of my nikon zoom)... thoughts thoughts thoughts...
  13. Piero

    TSA120 first light

    Great report Gerry, and glad to hear that it's all working very well!
  14. Thanks @mark81 I used this scope a lot in the past. There are some reports here on SGL already.
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