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Moonshane

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Posts posted by Moonshane


  1. 13 hours ago, John said:

    The colour of the scope was only small one part of the package of the scope that I linked to. The specification of the scope, the mount and it's price all added up to what I felt was a poor deal for the budding astronomer. If the price had been £25 then I would not have thought to mention it.

    I suspect that I've no chance of redeeming this thread though so fair enough. Apologies to those who I might have inadvertetly offended.

    As the saying goes, "the first thing to do when you are in a hole is to stop digging"  :rolleyes2:

     

     

     

    Oh dear. Can't we even insult inanimate objects now? Truly it seems the end of any sort of deprecating humour is nigh. 

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  2. 12 minutes ago, BGazing said:

    Having trawled some threads for refractor measurement it appears that 2.6 GPC is around 2.46x when mounted on the diagonal and bino threaded directly on it and that the values are growing in a linear fashion with additional optical path, see here https://www.cloudynights.com/topic/397010-glasspath-magnification-factors-including-the-26/

    For every 100mm of additional optical length between bino and GPC there appears to be 1.6 increase in magnification, approximately.

    Mounting in front of BBHS T2 would add 48mm optical path, so 0.77 in plus, for a total of  3.23x.

    Mounting in front of T2 zeiss prism would add 38mm optical path so 0.6 mag more, total 3.06x.

    ZWO ADC body alone is 29mm, so 0.46 mag. If GPC is screwed into the diagonal, the magnification is 2.92x. Mounting bino on that ADC EP holder is probably around 17-18 additional millimetres, so around 0.28 more mag, altogether 3.2x. That's how it felt last night. :)  So mounting it in front of BBHS and in the default position with the ZWO brings to similar magnitude. If 2mm optical path male to male T2 ring is used instead of the EP holder this reduces magnitude to around 2.95x.

    I do not know whether mounting via Zeiss bayonette adds anything in comparison with the T2 nut ring. This combination  https://www.teleskop-express.de/shop/product_info.php/language/en/info/p7744_Baader-2456322---Schwerlast-T2-Wechselsystem.html is listed as 15mm optical path, but it is difficult to know how much it adds to the default option and is in any event a different construction of bayonette than the one used in MBII. But if one wants to use it to connect ADC to diagonal and allow for rotation it would apparently add 0.24x.

    Hope my math is correct, apologies if it is not. :)

    This is excellent info - thank you!


  3. Just had a read and for my f11 6" Newt, I hope I might just get away with no barlow for visual. I'll try it and see what the view is like.  The issue with a barlow would be that assuming 4x amplification, it would mean a 6.4m focal length LOL. This would make my 27mm Panoptic a high power planetary eyepiece at 237x.

    That said I am more likely I think to use my 120mm Equinox. Over the next week I am hoping to actually put the thing into play.


  4. I agree that mirrors should only be washed very carefully and if required. Yours sounds very normal and is unlikely to be badly affected.

    The mirrors are coated with a few atoms thick coating to achieve the reflectivity and this is easily scratched. A scratch would affect the view more than a sfew dust specks.

    All that said, cleaning them is easy with care

     

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