Help with glasses!

Hello to all

I have very recently become interested in astronomy. I am starting to
identify the constellations and have picked out andromeda galaxy just
lately.

My Fiancée is keen to learn also and I've tried to point out certain things
to her, including andromeda as it seems so prominent at the moment, however
I can't tell if we're seeing the same things.

We are using a reasonable pair of 10x50's that I find very easy to use,
however my good lady wears glasses (she has astigmatism and slight short
sightedness) and is struggling to focus the binoculars. Is it best that she
keeps her glasses on and tries to shield out the extra light that comes in
or would she do better taking them off (obviously this means that I can't
get the focus about right for her)?

Any help is greatly appreciated.

Many thanks

Steve

If those Binos are of a good brand, at lest one of the eyepieces should be
able to be adjusted so that she doesn't need the glasses. I have a pair of
20 x 80's and once I adjust the rightside eye view, I then refouce the whole
pair and most of the time have good views.



--
The Lone Sidewalk Astronomer of Rosamond

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"Steve & Lizzie" wrote in message
...
Hello to all

I have very recently become interested in astronomy. I am starting to
identify the constellations and have picked out andromeda galaxy just
lately.

My Fiancée is keen to learn also and I've tried to point out certain
things
to her, including andromeda as it seems so prominent at the moment,
however
I can't tell if we're seeing the same things.

We are using a reasonable pair of 10x50's that I find very easy to use,
however my good lady wears glasses (she has astigmatism and slight short
sightedness) and is struggling to focus the binoculars. Is it best that
she
keeps her glasses on and tries to shield out the extra light that comes in
or would she do better taking them off (obviously this means that I can't
get the focus about right for her)?

Any help is greatly appreciated.

Many thanks

Steve

Starlord wrote:
If those Binos are of a good brand, at lest one of the eyepieces should be
able to be adjusted so that she doesn't need the glasses. I have a pair of
20 x 80's and once I adjust the rightside eye view, I then refouce the whole
pair and most of the time have good views.

That will work as long as her astigmatism is mild. Binoculars don't
play well with an observer's astigmatism because the exit pupil is so
large.

I personally haven't had a problem with stray light with my glasses on
(although I do admit to liking the view better with them off), but that
might just be a matter of where I'm observing from.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

We are using a reasonable pair of 10x50's that I find very easy to use,
however my good lady wears glasses (she has astigmatism and slight short
sightedness) and is struggling to focus the binoculars. Is it best that she
keeps her glasses on and tries to shield out the extra light that comes in
or would she do better taking them off (obviously this means that I can't
get the focus about right for her)?


Hi Steve,

The focus adjustment of binoculars will correct for short and near sightedness. The other issue is astigmatism which binocular focus will not adjust for. It might be easier if your lady friend first try the binoculars in daylight. Have her remove her glasses see if she can focus the binos on a distant mountain or building. Something a mile or more away. Then, without changing the focus setting of the binos, have her try them at night.

..Florian

Steve & Lizzie wrote:
Hello to all

I have very recently become interested in astronomy. I am starting to
identify the constellations and have picked out andromeda galaxy just
lately.

My Fiancée is keen to learn also and I've tried to point out certain things
to her, including andromeda as it seems so prominent at the moment, however
I can't tell if we're seeing the same things.


With binos, a stable mount (like a parallelogram
mount) is best. That way you can be certain you
are looking at the same view.

Phil

On Tue, 19 Sep 2006 15:13:24 -0700, "Starlord"
wrote:

If those Binos are of a good brand, at lest one of the eyepieces should be
able to be adjusted so that she doesn't need the glasses. I have a pair of
20 x 80's and once I adjust the rightside eye view, I then refouce the whole
pair and most of the time have good views.

It depends. The original poster said she has some astigmatism, which
means she'd want to keep her glasses on. If she has a lot of
correction for sphere she might not be able to get binoculars to focus
on distant objects. Most binos can accommodate +/- 6 diopters. If
her correction is more she'll need to keep her glasses on while using
the binoculars.

--
The night is just the shadow of the Earth.

If it's not to bad it should be ok, I know, as I have it too and yet I can
take off my glasses and use my binos just fine.


--
The Lone Sidewalk Astronomer of Rosamond

Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
Astronomy Net Online Gift Shop
http://www.cafepress.com/astronomy_net
In Garden Online Gift Shop
http://www.cafepress.com/ingarden
Blast Off Online Gift Shop
http://www.cafepress.com/starlords
Astro Blog
http://starlord.bloggerteam.com/




"William Hamblen" wrote in message
...
On Tue, 19 Sep 2006 15:13:24 -0700, "Starlord"
wrote:

If those Binos are of a good brand, at lest one of the eyepieces should be
able to be adjusted so that she doesn't need the glasses. I have a pair of
20 x 80's and once I adjust the rightside eye view, I then refouce the
whole
pair and most of the time have good views.

It depends. The original poster said she has some astigmatism, which
means she'd want to keep her glasses on. If she has a lot of
correction for sphere she might not be able to get binoculars to focus
on distant objects. Most binos can accommodate +/- 6 diopters. If
her correction is more she'll need to keep her glasses on while using
the binoculars.

--
The night is just the shadow of the Earth.

"Steve & Lizzie" wrote:

My Fiancée is keen to learn also and I've tried to point out certain things
to her, including andromeda as it seems so prominent at the moment, however
I can't tell if we're seeing the same things.

A mount would remedy that problem -- and allow you to see more detail
at the same time!

We are using a reasonable pair of 10x50's that I find very easy to use,
however my good lady wears glasses (she has astigmatism and slight short
sightedness) and is struggling to focus the binoculars. Is it best that she
keeps her glasses on and tries to shield out the extra light that comes in
or would she do better taking them off (obviously this means that I can't
get the focus about right for her)?

Assuming the astigmatism is the cause behind the struggle to focus the
binoculars, then yes, your lady should use the binoculars with her
glasses on.

This assumes that the eye relief of the binoculars allow for
comfortable use with eye glasses. If this isn't the case, then it
would be good for your lady to get her own pair of binoculars that are
more suitable to her needs.

If the binoculars were mounted, she would be able to drape a dark
cloth over her head and the back of the binoculars to block out stray
light. Alternatively, you could try to find a spot to observe from
where a wall, building, tree, vehicle, etc. blocks offending lights.

You *have* explained to her how to focus binoculars have you not? She
should place a lens cap over one objective (the one who's eyepiece is
individually adjustable), look through the binoculars and adjust the
focus until stars are as small as they'll get; then transfer the lens
cap to the other objective and use the individual eyepiece adjustment
to adjust the focus of that eyepiece. Then, of course, remove the
lens cap and she should be good to go -- until you re-focus for *your*
eyes!

Willie R. Meghar
http://meghar.blogspot.com/

"Willie R. Meghar" wrote in message
...
[snip]

Assuming the astigmatism is the cause behind the struggle to focus the
binoculars, then yes, your lady should use the binoculars with her
glasses on.

[snip]

You *have* explained to her how to focus binoculars have you not? She
should place a lens cap over one objective (the one who's eyepiece is
individually adjustable), look through the binoculars and adjust the
focus until stars are as small as they'll get; then transfer the lens
cap to the other objective and use the individual eyepiece adjustment
to adjust the focus of that eyepiece. Then, of course, remove the
lens cap and she should be good to go -- until you re-focus for *your*
eyes!

Assuming that this lady wears her glasses when observing and ALSO assuming
that those glasses restore her astigmatism AND nearsightedness CORRECTLY, the
above procedure isn't really needed.

I have -4.5/-4.75 and cylinder -1.0/-1.25. When I wear my glasses and focus my
binos using the method above, the binos and my scope come up to "focus at
infinity" and the adjustable eyepiece (on both my bino pairs) rests exactly at
+/- 0.

Therefore, my "focus at infinity" position with me WEARING my glasses (which
perfectly correct my vision) is exactly the same as the "focus at infinity"
for a person with 20/20 vision and no problems.

Conversely, when vision is bad, either because the sky is twinkling or because
my eyes are tired, I know I need to adjust ONLY the focus knob and not the
separate eyepiece knob, because the focal difference between my eyes is going
to be 0 when I wear my glasses.

Thus, when I want visitors to come see through my scope or binos, I focus
either, using myself WITH glasses, and then, when they look, for them the
scope or binos are perfectly focused at infinity, so they see fine through the
scopes.

The above method you describe is needed only when a person doesn't wear
his/her corrective eyeglasses or if the eyeglasses are old and don't restore
vision perfectly.

To summarize: A scope's focusing parameters for a person with pathological
vision and with corrective glasses ON are going to be equivalent to the
focusing parameters of a person with 20/20 vision, with the focusing knob set
at "infinity" and the individual eyepiece knob set exactly at 0, provided the
eyeglasses restore vision to 20/20.

Put in different words: From the scope's optical point of view, an eyeglass
corrected eye is equivalent to a 20/20 perfect vision eye, provided the
eyeglass correctly restores the person's vision for that particular eye.

The above has been my experience with many different viewers for my 11x80,
20x100 and my 60mm Tasco scope.

Willie R. Meghar
--
Ioannis
-------
The best way to predict reality, is to know exactly what you DON'T want.

Thanks everyone for all the good advice - looking forward to trying on the
next clear night!

Steve

"Steve & Lizzie" wrote in message
...
Hello to all

I have very recently become interested in astronomy. I am starting to
identify the constellations and have picked out andromeda galaxy just
lately.

My Fiancée is keen to learn also and I've tried to point out certain
things
to her, including andromeda as it seems so prominent at the moment,
however
I can't tell if we're seeing the same things.

We are using a reasonable pair of 10x50's that I find very easy to use,
however my good lady wears glasses (she has astigmatism and slight short
sightedness) and is struggling to focus the binoculars. Is it best that
she
keeps her glasses on and tries to shield out the extra light that comes in
or would she do better taking them off (obviously this means that I can't
get the focus about right for her)?

Any help is greatly appreciated.

Many thanks

Steve