7X50 or 10X50 binoculars for older viewers

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Date: 17 Aug 2006 15:08:16
From: brucegooglegroups
Subject: 7X50 or 10X50 binoculars for older viewers

I am researching buying some binoculars for astromony viewing, but also
for some day time viewing as well. I read a number of threads from this
group. Are the 10X50's better for middle aged eyes? I am leaning
towards 7X50s. I also do not look into my telescope with eyeglasses.

Thanks.
Bruce

Date: 17 Aug 2006 22:57:28
From: Willie R. Meghar
Subject: Re: 7X50 or 10X50 binoculars for older viewers

"brucegooglegroups" wrote:

>I am researching buying some binoculars for astromony viewing, but also
>for some day time viewing as well. I read a number of threads from this
>group. Are the 10X50's better for middle aged eyes? I am leaning
>towards 7X50s. I also do not look into my telescope with eyeglasses.

If your dark adapted pupils are less than 7mm in diameter you would be
wasting part of the 50mm apertures when using the 7x50s.

50mm binoculars tend to be a bit large and heavy to carry while
hiking. They tend to get 'larger' and 'heavier' as the day
progresses.

10x binoculars are at or near the hand holdable limit of many
observers. This means that for some observers hand held 10x
binoculars, used in the daytime, would have little or no advantage
over a somewhat lower powered binocular. At night, when one tends to
be looking at star fields and faint fuzzies, the shaking is less
harmful; but point them at the moon looking for fine detail and you'll
likely end up wishing you had a solid mount.

In my experience the smaller exit pupils and higher magnifications of
8x42 binoculars often provide better dark sky performance than 7x50
binoculars. The 8x42s are smaller and lighter in weight -- better to
carry while hunting or hiking. (I own 8x42 as well as 7x50, 20x80 and
25x100 binoculars.)

Thus, for dual purpose day/night use I would suggest 8x42s as an
alternative to the 50mm options you've been considering.

Willie R. Meghar

Date: 17 Aug 2006 18:52:10
From:
Subject: Re: 7X50 or 10X50 binoculars for older viewers; Scenix 7x50?

Astro-physics has just started selling a relatively low cost
($375-$385) line of binoculars. You might want to check them out
before you finalize your decision. I have no direct knowledge,
however, the AP crowd has given them some good reviews.

Date: 19 Aug 2006 00:44:38
From: Tim Killian
Subject: Re: 7X50 or 10X50 binoculars for older viewers; Scenix 7x50?

muddy@despammed.com wrote:
> Astro-physics has just started selling a relatively low cost
> ($375-$385) line of binoculars. You might want to check them out
> before you finalize your decision. I have no direct knowledge,
> however, the AP crowd has given them some good reviews.
>

I had a chance to use a pair of the new AP 10X70s last weekend. They are
pretty good optically, but they weigh a ton so a tripod comes in handy
for any extended viewing. There is no center focus and each eyepiece has
to be set independently.

Date: 17 Aug 2006 16:32:42
From: brucegooglegroups
Subject: Re: 7X50 or 10X50 binoculars for older viewers; Scenix 7x50?

Thanks for your replies. I was thinking of buying the Scenix 7X50s
from Orion. They look like a good deal.
Bruce
Martin R. Howell wrote:
> On 17 Aug 2006 15:08:16 -0700, brucegooglegroups wrote:
>
> > I am researching buying some binoculars for astromony viewing, but also
> > for some day time viewing as well. I read a number of threads from this
> > group. Are the 10X50's better for middle aged eyes? I am leaning
> > towards 7X50s. I also do not look into my telescope with eyeglasses.
>
>
> You didn't mention how dark your skies are. Dark skies can make a pair of
> 7 x 50's an incredible tool. My skies are only 5th magnitude at best
> (well, at least before the "roundabout" lighting ruined them) and my 7 x
> 50's always pleased me. I have never looked through any that were larger
> so I may not know what I am missing and that is okay. Ignorance is bliss.
>
>
>
> --
> Martin R. Howell
>
> "The Astro Post"
> www.theastropost.com
>
> --
> Posted via a free Usenet account from http://www.teranews.com

Date: 17 Aug 2006 16:32:42
From: brucegooglegroups
Subject: Re: 7X50 or 10X50 binoculars for older viewers; Scenix 7x50?

Date: 17 Aug 2006 16:15:43
From: Martin R. Howell
Subject: Re: 7X50 or 10X50 binoculars for older viewers

On 17 Aug 2006 15:08:16 -0700, brucegooglegroups wrote:

> I am researching buying some binoculars for astromony viewing, but also
> for some day time viewing as well. I read a number of threads from this
> group. Are the 10X50's better for middle aged eyes? I am leaning
> towards 7X50s. I also do not look into my telescope with eyeglasses.

You didn't mention how dark your skies are. Dark skies can make a pair of
7 x 50's an incredible tool. My skies are only 5th magnitude at best
(well, at least before the "roundabout" lighting ruined them) and my 7 x
50's always pleased me. I have never looked through any that were larger
so I may not know what I am missing and that is okay. Ignorance is bliss.

--
Martin R. Howell

"The Astro Post"
www.theastropost.com

--
Posted via a free Usenet account from http://www.teranews.com

Date: 17 Aug 2006 15:50:18
From: RMOLLISE
Subject: Re: 7X50 or 10X50 binoculars for older viewers

Phil Wheeler wrote:

> >
>
> Either will have an OK exit pupil .. but 7x is easier to hand hold than 10x.
>

Thw 10x will show considerably dimmer stars, however. Binoculars,
decent binoculars, are amazingly inexpensive now. What do we have and
use here:

12x35. Canons. Dorothy likes these. They are well made and peform very
well.

7x50. We have a Simmons "Redline" pair from some years back that we
picked up at WallyWorld. Amazingly good.

10x50. Ditto the inexpensive Celestron 10x50s Dorothy won at a star
party.

15x70. One of the best items Burgess sold (Bill seems to be somewhat
out of the binoc business now). Images comparable to the Fujinons, but
these are lighter. Not as well built, of course, not even close...but
I'm less reluctant to throw 'em in the back of the car or take 'em out
for occasional viewing at a pool/patio party.

16x70 Fujinons have the best images of the bunch, are relatively light,
and are nitrogen filled.

We find uses for 'em all.

Peace,
Rod Mollise
Author of:
Choosing and Using a Schmidt Cassegrain Telescope
and
The Urban Astronomer's Guide
<http://skywatch.brainiac.com/astroland >
The Annual SCT User Imaging Contest is Underway!
<http://www.rothritter.com/contest/2006/ >

Date: 17 Aug 2006 22:15:46
From: Phil Wheeler
Subject: Re: 7X50 or 10X50 binoculars for older viewers

brucegooglegroups wrote:
> I am researching buying some binoculars for astromony viewing, but also
> for some day time viewing as well. I read a number of threads from this
> group. Are the 10X50's better for middle aged eyes? I am leaning
> towards 7X50s. I also do not look into my telescope with eyeglasses.
>
> Thanks.
> Bruce
>

Either will have an OK exit pupil .. but 7x is easier to hand hold than 10x.

Phil

Date: 17 Aug 2006 16:02:55
From: G.T.
Subject: Re: 7X50 or 10X50 binoculars for older viewers

"Phil Wheeler" <wt6uh-ng7@yahoo.com > wrote in message
news:mU5Fg.1354$YC3.135@tornado.socal.rr.com...
> brucegooglegroups wrote:
> > I am researching buying some binoculars for astromony viewing, but also
> > for some day time viewing as well. I read a number of threads from this
> > group. Are the 10X50's better for middle aged eyes? I am leaning
> > towards 7X50s. I also do not look into my telescope with eyeglasses.
> >
> > Thanks.
> > Bruce
> >
>
> Either will have an OK exit pupil .. but 7x is easier to hand hold than
10x.
>

I'm 43, I have the Oberwerks 11x56s and I wouldn't trade them for anything.
For astronomy I'm a little shaky holding them while standing unless I'm
leaning against a tree or something. Sitting in a chair with armrests
they're perfect.

At $100 they far, far exceeded my expectations.

Greg

Date: 18 Aug 2006 05:22:54
From: Darian
Subject: Re: 7X50 or 10X50 binoculars for older viewers

tony_flanders@yahoo.com wrote:
> brucegooglegroups wrote:
>
> > I am researching buying some binoculars for astromony viewing, but also
> > for some day time viewing as well. I read a number of threads from this
> > group. Are the 10X50's better for middle aged eyes? I am leaning
> > towards 7X50s.
>
> You might also consider something like 8x40's. Lighter than 7x50's yet
> they'll
> probably show as much or more for astronomical purposes, and definitely
> easier to handhold than 10x binoculars. A nice compromise between astro
> and terrestrial use.
>
> - Tony Flanders

Tony, I agree with your advice. I have a pair of Celestron 7X42
Ultimas(no longer made) that are extremely light weight & relatively
compact. I had some Fuji 7X50s IF that were great binoculars; fantastic
contrast & image quality. They excelled for astronomy & the quality of
construction couldn't be beat. I eventually sold them from lack of use,
however.

The Ultima is good for scanning the skies & general daytime use.
Darian Rachal

Date: 18 Aug 2006 05:02:01
From:
Subject: Re: 7X50 or 10X50 binoculars for older viewers

brucegooglegroups wrote:

> I am researching buying some binoculars for astromony viewing, but also
> for some day time viewing as well. I read a number of threads from this
> group. Are the 10X50's better for middle aged eyes? I am leaning
> towards 7X50s.

You might also consider something like 8x40's. Lighter than 7x50's yet
they'll
probably show as much or more for astronomical purposes, and definitely
easier to handhold than 10x binoculars. A nice compromise between astro
and terrestrial use.

- Tony Flanders

Date: 18 Aug 2006 10:40:11
From: nytecam
Subject: Re: 7X50 or 10X50 binoculars for older viewers

brucegooglegroups Wrote:
> I am researching buying some binoculars for astromony viewing, but also
> for some day time viewing as well. I read a number of threads from
> this
> group. Are the 10X50's better for middle aged eyes? I am leaning
> towards 7X50s. I also do not look into my telescope with eyeglasses.
>
> Thanks. Bruce

Not sure anyone has really answered you query re 'older viewers' which
I imply means possible reduction on iris size of fully dark-adapted
eyes with advancing age. If the exit pupil from the bins is greater
that the dilated pupil then the eye effectively stops-down the bin
aperture.

7 x 50 bin gives an exit pupil [50/7] of ~7mm and if you eye pupil can
only manage say 5mm aperture the bins become 7 x 35 [35/5=7] and you've
lost half the bins light grasp! 10 x 50 = 5mm exit pupil so in the same
conditions all the light will be used!

This 'rule' will apply to any scope and why, for example, astronomers
don't 'view' through the 10m Keck telescope which would need a power
x1428 to get all the light through a young eye with just 7mm pupil.
There is another factor - if the object is bright, as seen at the
eyepiece, the eye will automatically stop-down eg reduce the pupil size
further - eg a loose-loose situation!

Nytecam 51N 0.1W

--
nytecam

Date: 17 Aug 2006 23:00:27
From: deb and todd
Subject: Re: 7X50 or 10X50 binoculars for older viewers

I have Pentax 10x50's. I love them and they have enough eye releif that
I can use them with my glasses on.

They make a great tool for finding astronomy objects and scanning the
night sky. That said, if I'm studing an object at night, I generally
use them on a small tri-pod with a quick release plate.

I find, I can't hold them steady enough to actually study an object for
a period of time.