Magnification needed to split tight doubles

I have often seen people here write about "how much magnification a tight
double requires to split, with this or that scope".

One curious phenomenon which I have observed with my surgically modified
Tasco, is that if the Tasco IS able to split the double I am looking at, I
perceive it as split on ANY magnification the Tasco zoom EP provides.

For example, Ras Algheti (~3.6") is at the practical separation limit of my
60mm/700mm Tasco. On VERY clear nights, I see it split even at
magnifications of 31x. Increasing the magnification with the zoom, only
increases the separation between the components, but the components ARE
visible as distinct, even at the lowest magnification. They are really close
to each other, but my eye clearly sees two separate stars there.

Since resolving power is dependent only on aperture theoretically, shouldn't
this be true for any scope? If for example your scope resolves epsilon
Lyrae, shouldn't it resolve it even at its lowest magnification?

I know the opposite is true: If your scope's HIGHEST magnification cannot
resolve a certain double, certainly no lower magnification will be able to
do it.

So I wonder, what exactly is the meaning of "my scope requires magnification
x to split double y". Maybe related to a more "subjective" perception where
the viewer requires the split to be "clean" and "comfortable"?
--
Ioannis

.

Relevant Pages

  • Re: Magnification needed to split tight doubles
    ... with this or that scope". ... Tasco, is that if the Tasco IS able to split the double I am looking at, I ... perceive it as split on ANY magnification the Tasco zoom EP provides. ... shouldn't it resolve it even at its lowest magnification? ...
    (sci.astro.amateur)
  • Re: Tal 2m or Explorer 150/200?
    ... The scope seems to bear some ... The eyepiece screws,should make no difference to the focussing. ... > observing but the chaps at Telescope House stillreckoned it would ... > tempting to push the magnification beyond the 10mm Plossl and 2x Barlow ...
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    ... do have the JMI installed between the scope and the Televue, ... image scale was smaller than with the 3x barlow. ... Powermate 5x (and thereby get less overall magnification once the filter ... these are effectively complete 'scope' assemblies used to ...
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  • Re: Viewing by eye versus astrophotography
    ... achieve a high effective exposure time, ... Is that where the scope tracks on both axis, in case you haven't pointed the scope correctly at the Pole? ... magnification is presumably determined by the focal length of the ... For high resolution, with the sort ...
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