binoviewers

I was contemplating the purchase of a good quality binoviewer and two identical eyepieces for viewing. Not just for myself but so my 4yo daughter can look through it easy and I can set up my telescope at community events and let people look through it in a more natural less narrow field of view.

So if you have a binoviewer and use it a lot, like gazing at the stars through one, could you please reply with the brand and model you are using?

Also a second question, what is a good FoV to look at in an eyepiece when used with a binoviewr? Is having two 83degree naglers about right or am I going to overlap? Maybe get two 50degree?

I've not actually tried showing people the sky
through a bino at public events, but I might have
some concern that people will need a lot of
help from you to use them properly. Each person will
need it re-set to their interpupilary distance, and
refocused for each eye. It might work with a
group of 3 or 4 people where you can spend 5 minutes
or so with each person, but I think a big group
with 20 to 30 people is not going to work out.
Probably half the people would end up seeing through
only one of the eyepieces anyway. Maybe folks
who have tried it on large public groups can chime-in.

I've used the Zeiss Mk IV and Denkmeier II (or
whatever they called it). Both work pretty well.
The optics are a little better in the Zeiss
but the Denkmeier has a wider range of add-on
optics for use in Newtonians, etc.

Choosing eyepieces for a bino involves many
personal factors, so its hard to give accurate
specific recommendations. Stuff like the shape
of your face, size of nose, distance between
eye pupils, whether you wear glasses, etc.
will become important. If you intend to use
this with the public, I'd try to go for some
lowest common denominator choice -- something
with smallish barrels and long eyerelief.
Perhaps some 50 degree Plossls in the
25mm to 30mm range. The longer focal lengths
will be better, since the exit pupil will
be larger and more tolerant of errors setting the
inter-pupilary distance. I like the old 30mm
Celestron Ultimas but they are hard to find
these days.

If you were the only person using it, then
I might suggest other choices like the
19mm and 24mm TeleVue Panoptics. These are very
nice, but the eyerelief is pretty short.
Nagler type 6 are nice also, but take some
getting used-to in the bino. The field edges are
harder to see, since you can't move your head around
like you might with a single eyepiece. The
Nagler 13mm type 6 is very nice, but again I'd
hesitate to suggest it for public use --
I think many folks would end up looking through
only one of the eyepieces.

Todd Gross has some useful info:
http://www.weatherman.com/nagler3.htm

You might check on your daughters inter-pupillary
distance and compare to units you are looking at.
I'm not sure, but it could be a problem. If you
can't get the eyepieces close enough, she's only
going to see through one of the eyepieces.

Micheal Fields said:

I was contemplating the purchase of a good quality binoviewer and two identical eyepieces for viewing. Not just for myself but so my 4yo daughter can look through it easy and I can set up my telescope at community events and let people look through it in a more natural less narrow field of view.

I love the Denkmeier binoviewers. For myself. For the public and little folks? Not So Much. They find them more difficult and annoying to use than fun.