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View Full Version here: : Binocular bang for buck


StutzJr
03-01-2014, 12:55 AM
I had spoken to my folks about getting an armillary sundial for my backyard for christmas. We didn't have much luck in tracking one down so my dad has offered to get me a pair of binoculars instead.
He's got a old pair of carl zeiss 7x50 binoculars that are quite good and we were talking about them on new years eve on their balcony. While we were waiting for the fireworks I had set up my 20x50 Typnct-3 refractor to observe the orion nebula. He showed me that it was a much better view using his 7x50 binoculars and I agreed.

So I'm now looking at options for a pair of binoculars for astronomy usage, with a budget of $200 (any more I will have to contribute myself). I'd really like a pair that would be good for planetary viewing on par with my 6" dobsonian scope. I've been looking at some of the ones on andrews comms page and am trying to figure out what would be the best size to consider?

There's a nice one listed as a "Giant 20 X 80 TRIPLET semi-APO binoculars" which looks fantastic. I'd need to contribute a little to that one but it does come with a metal case. But I figure at 2kg I would need to spend almost that much again on a decent mount* as my tripod probably couldn't handle it.
Another is listed as "High contrast BBFMC 11 X 70 binoculars" which also looks pretty good. That one is only 1.6 kg and inside the budget so I could throw in a collimation eyepiece for my dob in the same order as well.

*I try to stick to purchasing gear that I can use now and continue to use when I eventually upgrade beyond my 6" dob. I've got a gso 2.5 barlow some gso plossl eyepieces and a 8x50 right angle finderscope and various other things that will continue to come in useful later. I can't justify spending a lot on a mount just for some fancy binoculars right now, unless it could also be used for a larger OTA later as well. (However I was interested in the "binotrolley (http://www.iceinspace.com.au/forum/showthread.php?t=115344)" thread on this forum)

Generally what is a good size to consider for planetary viewing, what are the tradeoffs, and what is the easiest method for viewing near zenith without neck strain?

edit: I forgot to mention, the other option I am considering is a binoviewer eyepiece for my dobsonian scope. As mentioned above it would be another good tool in the kit. Any cons to using a binoviewer with a 6" dob?

StutzJr
03-01-2014, 01:44 AM
...and at 1:30 AM I come across this page:
http://www.cloudynights.com/photopost/showphoto.php?photo=1377&password=&sort=7&thecat=500

I wasn't sure whether to ask:
Does this thing come with goto?
*or*
Is this guy related to Davros?!

Shark Bait
03-01-2014, 07:13 AM
This sounds like a big ask of binoculars. Most binoculars are good at wide field views and will allow for some planetary observation, but this must be within realistic expectations.

My 7x50's will show Mars as a tiny red/orange disc. Jupiter is a bright disc with its largest moons looking like faint stars. On a night of good seeing, I can just make out that Saturn has something going on besides the disc (at 7x magnification, I can't quite make out the ring system). Venus is so bright (and small), that it is very hard to get an idea of the phase.

I always have my binoculars with me when observing, but the bino's and telescope are used for different purposes.

brian nordstrom
03-01-2014, 08:28 AM
:)Stu is right here , bino's and telescopes are different beasts .
I had a pair of 25x100 binos that HAD!! to be mounted and even at 25x the planets were small , Saturn showing its rings , Jupiter hinting at its bands with moons easily seen etc .. but the moon was awesome ( being so large anyway )
If you use binoculars where they excel , thats wide field upright viewing of star clusters , nebular etc , you wont be disappointed , stick with your scope for lunar/planetary viewing .
Brian.

StutzJr
03-01-2014, 10:14 AM
Thanks for the correction! I'm not sure what I was thinking there, it was a bit of information overload last night. What I meant to say was I would like a pair of binoculars that give a similar performance in terms of "effective" aperture, a workmate had told me once to remember that binoculars gathered twice as much light for a given aperture. I was trying to find a quantitative description of this.
Anyway I am leaning toward the bbfmc 11x70 pair, since that seems like a good tradeoff between light gathering, mag, price and usability. I'm not sure how to compare a 11x70 to a 15x70 because the site describes the 11x as having better sharpness and contrast?