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C8 vs 4 inch frac bino/mono on planets

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#1 BGazing

BGazing

    Apollo

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Posted 13 July 2020 - 04:17 AM

Title says it, let's leave out 12 inch dob from the signature, ultralight and not really made to be used on planets this low.

I've tried both scopes on several consecutive nights, both in bino and mono mode (mono with and without ADC). Seeing was meh on two nights and plain horrible on the third night. Could not focus above 150x, if at that.

Leaving Uranus and Neptune, who are clearly C8 territory due to being small and requiring ooomph and magnification, some impressions:

- Zero glare on Jupiter and Saturn in refractor, no glare in C8 on Saturn but Jupiter is soft and glarey. Seeing was bad, alright, but C8 seems to impart a lot of scatter...is that due to bigger exit pupil? I get no glare on Saturn in C8, probably due to lower surface brightness. What's the cure, Neodymium or just 'live with it'?

- Bino vs mono(with ADC). ADC improves views in mono, especially in bigger aperture, but also in 4 inches. But here's the thing, using binos in refractor... I could live without ADC (sort of 6 of those or half a dozen thing), but in C8 binos were inferior to mono w/ADC because the dispersion was intrusive and evidently killing the image quality. So I settled on binos in Tak (for relaxation) and mono w/ADC in C8. 

- MBII binos have a very mild polarization effect and I could not perceive too much dimming. 150x in 4 inch refractor and Jupiter was okay.

 

So what's with Jupiter and scatter in C8? Night was not dewy (oh, I know those, there's glare even in Tak), rough mirror (surely it cannot match fluorite), just too much exit pupil?

 

Is Mars the same story? I remember using 212x in mono on it in 4 inches, I guess dimming it in C8 woud require at least 250, and seeing has to cooperate. Binos on Mars or just cranking up power in mono until you run out of magnification?


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