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John

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Posts posted by John

  1. 45 minutes ago, Stu said:

    Actually, it is not a case of Fluorite scope good, fpl scope bad, far from it. Many factors are important, the mating element material, the design, figure and polish of the elements, the cell design and manufacture etc etc. A number of high end manufacturers get this right....

    Indeed. My TMB / LZOS 130 uses neither Ohara FPL or Fluorite. LZOS use their own proprietary glass types (OK4 and OF-1) in their objectives and I believe don't make this available to any other optical manufacturer. The results judging from my example are very, very good :icon_biggrin:

    • Like 2
    • Thanks 1
  2. 1 hour ago, F15Rules said:

    "Here is a short post I made on the CN forum comparing the two:"

    I saw that thread John, interesting read. I think any F9 scope will give sharper and better star tests than  an F6.5, (given equal quality glass etc) if only because the elements have gentler curves which are easier to polish and figure?......

     

    ......That's why I'd love to see a premium F11-F13 ED or Fluorite doublet offered. It would sit well on an EQ6 class mount and would genuinely be a double star killer I reckon.

    But I know it will never happen, not enough demand for a long, expensive modest aperture apo, so the economics probably wouldn't add up. And it's much easier to stack F7 or 8 100mm tubes on a pallet!

    Dave

    My ED102SS replaced a Skywatcher ED100. I was expecting a slight drop in CA control and possibly sharpness but I didn't see it to be honest. The lens is well figured in the F/6.5 Vixen but the Tak is even better.

    FrT Telescopes do an F/12.5 120mm ED doublet refractor. Quite expensive though:

    http://www.frtelescopes.com/frt120ded.html

  3. I have to say that I feel the prices for the 35mm Eudiascopic are a little on the steep side if they are the same as the old Celestron Ultima 35 and Orion Ultrascopic 35 :undecided:

    Last time I bought a used Ultima 35 (which was a few years back admittedly) I think I paid around £45 for it, delivered :icon_scratch:

     

     

    • Like 1
  4. Just now, 25585 said:

    I have been considering the 40mm TV plossl, as though its got the same TFOV as my 32mm, the images though smaller will be brighter when used as a finder ep. Also its 31.7mm fit.

    I had one for a short while. I ended up using the 32mm much more because I didn't like the 43 degree AFoV of the 40mm as much and the 40mm is not par focal (by quite a few mm) with the other TV plossls. It's a very nicely put together 40mm plossl though.

     

    • Like 1
  5. 10 hours ago, Piero said:

    Never owned a Vixen telescope and probably never will, having a Tak. 

    I like their products a lot though. 

    I can recall a few years back there were rarely any posts on this forum about Takahashi products but quite a few folks had Vixen's of one type or another. Today Tak's seem to be much more frequently discussed so I'm assuming that the ownership levels are higher now. Or maybe my memory is playing tricks on me :icon_scratch:

     

  6. Can't see the pics of yours Dave :icon_scratch: (edit: oh yes I can now - very nice ! :icon_biggrin:)

    Here are pics of my old (I owned this around 1990) Bresser Uranus which was really a Vixen SP102M in a black colour scheme (complete with early Skysensor GOTO) and a couple of my current Vixen ED102SS toting it's Vixen handle and rings, care of your good self Dave plus Moonlite focuser. I've owned the ED102 for over a decade now :icon_biggrin:

     

     

    bresseruranus.jpg

    vix102ota01.JPG

    vix102ota02.JPG

    • Like 7
  7. 1 hour ago, Mak the Night said:

    Apart from a slight magnification difference, and a few aesthetic differences, I can't tell any visual difference between these two eyepieces in an f/5 refractor. There's a reason that there is £196 difference between these two eyepieces and it isn't anything to do with visual quality. It has everything to do with economic ideology. 

    So because you can't tell any difference thats it is it ?

    They are expensive so if you try them and they don't make any difference to you, don't buy them. Oh and by the way, the Nagler T5 16mm is made in Taiwan, not Japan. Most of the larger and more complex Tele Vue designs are made in Taiwan now.

    There are many very experienced observers around this planet who do use and value Tele Vue's products and other premium brands such as Pentax, Leica, Zeiss etc. This is not an accident and these folks are not just about showing off or throwing money away. They have found over years of comparisons that these brands do have a performance edge and they are prepared to invest as needed to obtain that.

     

    • Like 3
  8. 3 hours ago, FenlandPaul said:

    Well done John. I believe I bagged it last night as well (if you can really call it bagged - it seemed it was always trying to slip through my fingers). On first attempt the bite would come and go and I couldn't be certain. But returning to the eyepiece later, IC434 seemed ever so slightly more obvious but ever so slightly less obvious to the east and slightly south of the two stars (one of them is HD37699) that were my guidepost. The "bite" was real.

    Used 22mm Nagler with H-Beta filter, giving x69. 

    Whilst I was thrilled to have a positive sighting, I would be disappointed if I wasn't able to have a more convincing view at some point!! But I can now confirm, at least, that the HH really does exist!!

    Paul

     

    That sounds like the way I'm seeing it Paul. It does get a little clearer with subsequent viewings but I think I'd need to go to darker skies to take the definition up a notch (apt word !) further. The skies don't get much better for DSO's here than they were last night and on the previous sighting.

    I'm still very pleased to be able to detect this target at all from my back garden. I'd almost written it off last year :rolleyes2:

    • Like 2
  9. 34 minutes ago, Littleguy80 said:

    Great result, John. Really is lovely out there tonight. Do you think the HH was easier second time around? 

    The cold and windy conditions made it less comfortable (ie: harder to stay at the eyepiece and concentrating !) but having found it before helped in terms of realising that it might be "on" tonight and zeroing in on the right patch of sky.

    So thats a "yes and no" answer ! :smiley:

     

    • Like 1
  10. Heres a nice planetary nebula currently well placed in Taurus, not far from the Pleiades. This evening with my 12" dob I found NGC 1514, AKA The Crystal Ball, hard to spot, as a nebula, but it's 9th magnitude central star is easy enough so the trick is to pinpoint that, then apply the O-III filter and, voila, the star is surrounded by a nice clear and reasonably large ball of nebulosity at 90x magnification. With careful examination some vague structure starts to appear across the nebulosity with the central star still shining boldly forth from it's centre. Without the filter and the star might easily be mistaken for any other - just the slightest haze surrounding it. I guess a UHC would have some enabling effect as well but the O-III makes a great deal of difference to this one, turning it from obscure to fascinating :smiley:

    This one was discovered by William Herschel on the 13th November 1790 and he described it as follows:

    " A most singular phenomenon !  A star of about 8th magnitude with a faint luminous atmosphere, of circular form, and about 3 minutes in diameter.  The star is in the centre, and the atmosphere is so faint and delicate and equal throughout that there can be no surmise of its consisting of stars; nor can there be a doubt of the evident connection between the atmosphere and the star."

    The overall magnitude of the nebula is given as 9.8 but my goodness it looks so much better with the O-III filter :thumbright:

    Here is the entry from the Observing at Skyhoud website with a nice locational diagram:

    https://observing.skyhound.com/archives/dec/NGC_1514.html

     

    • Like 8
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