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My swaro 8x20b are brighter than my Bushnell 8x42! (1 Viewer)

truculenter aspicientis

Well-known member
Just had chance to test against each other, the view though through the swaro 8x20b is brighter by a tad than my Bushnell birding series 8x42 but less than half the object lens diameter. Why's this?
Gloomy day...


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Not much use to compare them in daylight. If using an 8x42 and it's bright outside your pupils will be maybe 2mm so you cannot use the light of the 5.25 mm exit pupil of the 8x42. If your pupil is 2mm the 8x42 will work as an 8x16. Therefore the better coatings of the Swaro come into play and make it look brighter.
Try comparing them at twilight or for astronomy and I am pretty certain the 8x42 will be brighter and show more stars for instance or more details at dusk or dawn.
Unless your pupils are not reaching those 5.25 mm -- there won't be much of a difference in daylight.

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