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Burgess 25x100 vs Burgess 20x80

Started by Kimballcorson, 02/24/2003 12:47PM
Posted 02/24/2003 12:47PM Opening Post
Hi Group,

What are your thoughts on a purchase decision in choosing between these two binoculars, the price difference aside?

Kimball Corson
Posted 02/24/2003 01:34PM #1

Burgess 25X100: About 3 times the size and weight!

100 mm binos are huge. Don't expect to mount them with the average fluid head such as the Bogen 3126/3130. You will need the Bogen 501 head or the Burgess heavy oak parellO mount at minimum. I have the ProOptic 25X100mm which is much bigger than my Orion 20X80. The Burgess 100mm is several inch longer than my ProOptics and about 3 lbs heavier.

The Burgess 20X80 LW on the other hand are just a bit bigger than the popular 15X70 size. I can use the 20X80 LW with my elbows supported. Doing that with the 25X100mm is out of the question. However, a light weigh tripod such as the Bogen 3011/3021 is recommended when you want to do extended viewing.

I estimate I can see about 1/2 maganitude dimmer stars in 100mm binos than 80mm. Not somethin you'll notice easily. The TFOV in 25X100mm binos is about 2.5-2.6 deg. The narrower FOV does make it more difficult to locate objects compare to the 3.5 deg FOV in 20X80s.

I'd say go with 100mm if you already have 70mm binos. Otherwise I recommend trying the 20X80 LW first and wait for bigger binos or the 20/40X100 with 45 deg eyepiece from Burgess or Oberwerk.

Erik D
Posted 02/24/2003 01:38PM #2
Price aside, and all else being equal, meaning quality of glass, prisms, coatings, mechanical operation, etc., in my mind I say go for the magnification. The exit pupil of these two choices is the same, and if you want you can stop down the 100s to get a higher resultant system f and smaller exit pupil which may improve contrast, chromatic abberation and resolution.

The 100s will provide greater potential resolution and more light gathering power but the 25x is what allows you to utilize more of the potential. 25x80s would allow you to see more than 20x100s. It's not the increase from 80mm to 100mm that's going to show you the greatest leap in performance, it's the jump from 20x to 25x, if all else is equal. Of course, rarely is all else equal. Take note of Erik's comment on size and weight and what is required to mount this instrument.

Posted 03/24/2003 10:01PM #3
Hmm... still havent heard much about what owners of the 25x100's think of them and how they compare to... the 16x80, other 20x80 or even oberwerks x70's in day to day use.

$300 definitely seems like a helluva deal, but so is $150 for the 16x80s.

I love the 9x63 orions even at $189! Bueler... Beuler... ? ;-) Thanks!