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Vixen 50mm LV

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#1 asaint

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Posted 25 September 2003 - 06:20 PM

Vixen 50mm Review

#2 Wouter D'hoye

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Posted 27 September 2003 - 07:12 AM

Indeed, it is a nice eyepiece. Giving a sharp view to the edge. The missing of an eyecup is not it's only drawback. With some telescopes it might be difficult to reach focus because the fieldstop is located very deep inside the eyepiece. So it requires quite some inside focus travel.

But it is a very good value and the 2.5° field of view with a 4" f/8.8 apo is very nice.

On the other hand the 30mm version has a 2° field but a much darker sky background.

Anyway I like these eyepieces. Opitcally they are great but some adjustments would make them more practical to use. Recommended!

Kind regards

Wouter D'hoye

#3 Oldfield

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Posted 29 September 2003 - 10:08 PM

Seems like the 2" Widescan Type III is better, at similar price if we got it from Japan during a trip there.

#4 wilash

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Posted 30 September 2003 - 07:12 AM

Dear Oldfield,

The 30mm Widescan Type III is twice as expensive as the LV50 in Japan. The Widescan would have a slightly larger true field of view, but a much smaller exit pupil. I would think it is difficult to compare a 30mm eyepiece to 50mm eyepiece. What do you mean by "better."

Wil

#5 Oldfield

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Posted 30 September 2003 - 11:01 AM

in terms of maximizing the true field, maximum contrast due to more magnification.

to me, we usually want more field, instead of lower power or large exit pupil, unless aperture is limited.

#6 wilash

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Posted 01 October 2003 - 03:10 AM

So it is really personal preference rather than the 30mm Widescan being better. I have a 70 degree AFOV eyepiece and I am not really impressed. Your eye cannot take in the entire view and since I tend naturally to move the scope to starhop and center the target in the middle of the field, a large AFOV really has no great impact on observing. And in this case I can take in a larger area of the sky in one glance with the 50mm.

I do find a significant difference in image brightness between a 30mm and 50mm eyepiece. And I hate to disagree with you, but contrast decreases as maginification increases.

But really, the difference between a 30mm and 50mm eyepiece makes comparision very difficult. The difference in magnification, image brightness, and price alone negates any judgements. I think a comparision between the Pentax 40mm XL would be better. But, like the Widescan, it is twice as expensive.






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