Tasco World Class 8 by 25 roof prism compact
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- Joined: Thu Apr 15, 2004 11:07 pm
Exit pupil is a measurement of the magnification divided into the objective lens size. The same size binocular will always have the same exit pupil. 8x25mm binocular, 25 / 8 = 3.1mm exit pupil. 10x50 binoculars, 50 / 10 = 5mm exit pupil. Exit pupil is used in helping determine the best viewing conditions for a binocular.
A binocular with a 6 or 7mm exit pupil is great for use in dusk or evening hours, and for astronomy. 5mm is excellent for all around use, day or evening. Less than that is primarily for bright light activities.
Tasco does have many good quality binoculars for a low price. In Fact, I have a pair of Tasco Platinum, http://www.opticsplanet.com/tasco-pm840.html, at home that I use all the time.
Let us know if there is anything else we can do for you.
Phone: (888) 263-0356
Fax: (847) 574-6820
- Stan @ Opticsplanet
- Posts: 98
- Joined: Mon Jan 12, 2004 11:57 am
- Location: Chicago, Illinois