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View Full Version : Can anyone help choose a pair of binos?



seeker372011
2003-Dec-06, 12:32 PM
I have a couple of small telescopes and have been looking at adding a pair of binoculars for the portability and wide field of view; would anyone be able to advise me as to what' s best, I am considering either a Meade 9x 63 or a Celestron 15x 70 (which seems to be on special at the moment.)

Some resources on the net suggest that one should maximise the exit pupil for astronoomy as long as it is below 9 mm. On this consideration then a 9x 63 with an exit pupil of 7 is better than a 15x 70 with an exit pupil of only 4 and a bit.

On the other hand if that is the case then why would anyone make or buy the higher magnification binos? Or is that useful for non astronomical uses?or is it just marketing hype?

is anything other than a 7x 50 pointless for astronomy?

would really appreciate advice


seeker

Dave Mitsky
2003-Dec-06, 04:10 PM
If you're over 40 years old or observe from a light polluted area a binocular with a 7mm exit pupil is not a particularly good idea. For most people an exit pupil of 5mm will be more useful.

A 15x70 binocular will be difficult to hand-hold for any extended length of time. You will probably need a tripod or better still a tripod and a binocular guider, which you can build or purchase from companies like Virgo and T & T. (I own a Vista guider which I use with Celestron 20x80's.) Higher magnification and more aperture usually means better perfomance (multplying the two gives a rough index) so the added cost may be justifiable to you. If not a quality pair of 10x50's, the Celestron Ultimas for instance, is probably a better buy. Keep in mind that astronomical observing is the most demanding task for a binocular and requires good optics. Many of the cheap binoculars on the market today are made in China and are not exactly examples of optical perfection.

Some useful web sites:

http://www.stargazing.net/david/binoculars/

http://skyandtelescope.com/howto/scopes/ar...ticle_256_1.asp (http://skyandtelescope.com/howto/scopes/article_256_1.asp)

http://homepages.interscape.net/homeroom/r...files/binos.htm (http://homepages.interscape.net/homeroom/rascsite/rascfiles/binos.htm)

http://www.cloudynights.com/howtos2/binocu...performance.htm (http://www.cloudynights.com/howtos2/binocular-performance.htm)


Dave Mitsky

seeker372011
2003-Dec-08, 04:35 AM
Thanks Dave, the sites are really useful.

I know what you mean about the poor optics on the Chinese binos, I tried a pair of 15 x70s at an incredibly low price but had to return them, I have seen better, more crisp images using 7 x50s.

The net used to be full of warnings about buying Tasco telescopes, but these low cost binos are a lot worse!!

Skyywatcher
2003-Dec-16, 02:20 PM
A large set of binos will need a heavy tripod because the the binos are heavy and at the magnifications used, impossible to hold steady with the hands.
A pair of good quality binos in the range of 7x50 are, in my opinion, the best choice. Buy from a dealer close by so you can actually try them before you give away any hard earned money. At least $200 and up will get a decent pair. You need to remember that magnification is over rated. All you need is a decent field of view and crisp clear images. :rolleyes:

exAstro
2003-Dec-20, 02:23 AM
I recently purchased the Celestron Skymaster 15 by 70's for about 90$, delivered. I'm very happy with the optics and feel of these binocs. Hey, 80 bucks- you got to be kidding. Why, please tell me, pay 400$ for something 5% better.

seeker372011
2004-Feb-03, 11:19 AM
My new 20 x80s are here! :)

Well, after a bit of research and some humming and hawing I finally ordered a pair of Oberwerk 20 x 80s

They took three weeks to get here (Australia) and it has been cloudy tonight :( so I haven't had a chance to do any more than have a quick look at the moon and saturn. .. but so far so good.

I need to build a mount of course, it's impossible to hold these steady for any length of time in your hands, so I guess that's what I'll be doing this weekend....

Once I get some observing done with these I'll describe my experience on this forum in case anyone else is thinking of big binos


seeker

The Meal
2004-Feb-03, 03:25 PM
Originally posted by seeker372011@Feb 3 2004, 04:19 AM
I need to build a mount of course, it's impossible to hold these steady for any length of time in your hands, so I guess that's what I'll be doing this weekend....
I'd love to hear about your mount. I've a set of 10x50s that are a bit wobbly for any extended use that I should figure out a good mount for. I'd appreciate hearing any suggestions/experiences you have.

~The Meal

imported_iceman
2004-Feb-04, 08:53 PM
I've just ordered some Saxon 11x70 (in Australia).. I've heard they're better than the 15x70 simply because the increased magnification won't help that much.

I've also got a tripod off ebay (hopefully coming today) and a tripod adapter so hopefully I'll be ready to roll by the weekend.

I'm not 100% sure what to expect out them.. Currently I only have some compact 10x25 (not bought for astronomy, clearly) and of course they don't offer much more than the naked eye does.

It's my intermediate step before taking the plunge to buy a decent telescope, because from all I've read, if you can't afford a *good* telescope, don't buy one.. get some binoculars instead.

seeker how much did your binoculars cost and where did you get them from?

seeker372011
2004-Feb-05, 06:32 AM
Iceman, I bought the Oberwerk 20 x 80LWs from bigbinoculars.com in the US. Cost $199 (US) and shipping cost $50 (US) so all up it cost $330 Australian. It took three weeks to get here by EMS. No GST and no customs duty was payable.

I was able to take them out for a test drive last night and here's my feedback:

-definitely need a mount-after half an hour my neck really hurt. The image shakes too much as well even with elbows steadied on the arm rest of a chair

-20 x80s rock! I took my trusty old 7 x50s along and looked at all these objects as well. Amazing how much more detail you can see with these compared to the 7 x50s

-the gibbous moon was absolutely stunning. In some ways far better than through my 5 inch newtonian because the whole moon fits into the field of view and yet you see enough detail to make it interesting

-Eta carinae was simply superb! I sent a long time looking at this object. Like with the moon, it was different from looking at it through a scope and in some ways actually nicer

-M42 was an easy target (but I have to say I thought M42 is far more spectacular through my telescope)

-M41 was a bit washed out because of the bright moon

-Tuc 47 was quite large in the binos but pretty much a fuzz, couldn't resolve stars. still nice to look at though

-The Pleides again are better suited to this size binos because you can see the whole of this cluster which you can't with a scope. I couldn't see any nebulosity yesterday but remember the moon was really bright

-Mars was a small dot; Venus a disk

- and here's the surprise-unless I was dreaming I thought I could make out the very tiny rings of Saturn. I know this is not supposed to be possible with such low magnification but I could swear I saw them. And my wife and teenage son who are all used to looking at Saturn through scopes of various sizes by now also thought they could make out the rings. I was expecting a blob, so this-if I wasn't dreaming or it wasn't a once off quirk of light- was a clear bonus.

Now I can't wait to get my mount built and for the next new moon to see what these binos can really do

Yeah, I like these binos.

Dave Mitsky
2004-Feb-05, 04:40 PM
Originally posted by seeker372011@Feb 5 2004, 06:32 AM

-The Pleides again are better suited to this size binos because you can see the whole of this cluster which you can't with a scope. I couldn't see any nebulosity yesterday but remember the moon was really bright



Just for the record any good rich-field telescope such as an 80mm f/5 short-tube refractor can frame M45 (which spans about 2 degrees) in its entirety. I own a 101mm Tele Vue f/5.4 refractor that can produce a 4.4 degree true field of view using a 2" 35mm Tele Vue Panoptic ocular.

http://www.seds.org/messier/m/m045.html

Dave Mitsky