i want to use binoculars strictly for birding and im wondering which ones of these binoculars i should get that fall within my $100 budget (the type of birding ill be doing is watching birds in my backyard to out in wide open fields and tall trees, while wearing sun glasses):
Nikon 10x50 Action Binoculars 7218 - $99
http://www.opticsplanet.net/nikon-1...ulars-7218.html
Pentax 8x25 UCF X II - $89
http://www.opticsplanet.net/pen8xucfxbin.html
Pentax 8x40 XCF - $80
http://www.opticsplanet.net/pentax-8x40-xcf.html
Eagle Optics 8x42 Triumph Binocular - $69.99
http://www.opticsplanet.net/eagle-o...rs-triumph.html
Bushnell 8x42 Natureview Plus - $96
http://www.opticsplanet.net/bushnel...natureview.html
I'm confused on those nikon action bino's because opticsplanet says they're worth $215 but amazon says they're only worth $89 and are selling them for $79
In that price range you should look at the Nikon Sporter 8x36 or 10x36 - highly regarded for a budget bin.
That price for a Nikon action at $79 is correct - all bins were once new and commanded a premium price but it soon falls (some more than others).
If you wear glasses get binoculars that have at least 17mm eye relief or more. Then get the ones with the widest field. From your list the ones with the best resolution (assuming they have no manufacturing flaws) will be the Nikon 10 x 50's They will also be the heaviest of the one's you have listed and they will also be the brightest ones under overcast skies and twilight conditions. Also, a 10 x 50 binocular is a good binocular for casual astronomy. The Nikon's are the most versatile of the one's you have listed. Heavy but good. They will also be the best for hawk watching and on distant shore birds. Their 342 FOV isn't too bad for a 10 power bin. The 8x's you have listed will likely have wider FOV and better depth of field and will be lighter and easier to lug around. Try as many as you can before you decide. It's largely a personal thing in the long run.
Good Birding,
Bob