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Main
Date: 17 Aug 2006 05:32:15
From: pascal
Subject: which oculars for my mewlon 210 (f 11.5 / 2415mm)
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Hi,
I am wondering what would be the best 2 ocs for it. Anyone who has a
similar focal length , thanks for telling me which one they use most of
the time.
Thanks.
Pascal.
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Date: 17 Aug 2006 08:06:32
From:
Subject: Re: which oculars for my mewlon 210 (f 11.5 / 2415mm)
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pascal wrote:
> Hi,
>
> I am wondering what would be the best 2 ocs for it. Anyone who has a
> similar focal length , thanks for telling me which one they use most of
> the time.
In My U11 (FL=2800) and in my 20" DOB, my most used EPs in order of
usage are::
A) 31mm Nagler T5
B) 13mm Nagler T1
C) 9mm Nagler T1
D) 20mm Nagler T2
E) 7mm Nagler T1
Discounting the 7mm Nagler + 2X Powermate used for collimation duties.
I think that you will find wide angle viewing fun and relaxing. I use
the 31mm Nagler as a Super Finder (after pointing with the telrad) to
zero in on the object of desire. The 31mm Nagler is just perfect on M31
(especially with only 1500mm of FL) and good for lots of panning
duties.
After locating an object of desire, the next step in zooming in is
generally my 13mm for objects that are less than 1/3 FoV of the 31mm
Nagler, nice crisp views. For planets I generally just zoom up to 7mm
and skip the intermediates. THe powermate give me access to 10mm
(20mm*2), 6.5mm (13*2), 4.5mm (9*2), and 3.5 (7*2) {only used for
collimation). This gives me access to 10mm, 9mm, 7mm, 6.5mm and 4.5mm
for planetary work. {Maybe I should find an 8mm....}
So the trick, here, is to have one really wide EP (30mm range), an
intermediate EP (20mm range), and a selection of EPs that when
considered with a barlow/powermate do not actualy create overlapping EP
FLs. Consider the EPs of choice and start building with a plan in mind.
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Date: 17 Aug 2006 14:26:28
From: Willie R. Meghar
Subject: Re: which oculars for my mewlon 210 (f 11.5 / 2415mm)
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"pascal" <pascal_minvielle@hotmail.com > wrote:
>I am wondering what would be the best 2 ocs for it. Anyone who has a
>similar focal length , thanks for telling me which one they use most of
>the time.
If I had that telescope and was to limit myself to only two eyepieces
(oculars) I would want:
A 15mm Panoptic or similar design -- suitable for most deep sky
observing. (I've found 200x to be nearly ideal for most deep sky
observing with a 25cm Newtonian. 160x should be about right for your
telescope.)
An 8mm Orthoscopic, Plossl, or other relatively simple design for
high powered lunar and planetary observing (assuming the telescope is
on a driven mount -- otherwise an eyepiece with a well corrected,
wider field would be better).
Of course, in the real world I would want more than two eyepieces.
Sometimes I would want a lower magnification (and wider field) than
the 15mm provides; and I would want other 'high' powered eyepieces on
either side of the 8mm to take into account different objects and
different seeing conditions.
Willie R. Meghar
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