BirdForum is the net's largest birding community dedicated to wild birds and birding, and is absolutely FREE!

Register for an account to take part in lively discussions in the forum, post your pictures in the gallery and more.

Reply to thread

Message: <blockquote data-quote="phlazm" data-source="post: 3563062" data-attributes="member: 131862">Let me know if I'm asking this in the wrong place please, but I'm trying to get a feel for the difference between a porro with very high transmission and a roof prism with a larger diameter. In this case I'm looking at a Habicht 8x30w which has a 96% (maybe 98 I don't recall exactly) and a high end Zeiss or similar alpha bino with a 40 or 42 lens. Which would be brighter, the larger lens with lower transmission or the smaller lens with higher transmission?Yes, I'm splitting hairs and would probably be happy with either, but now I'm curious. I have a late Zeiss Classic 10x40 that is much brighter than a 1960s Habicht 8x30, but that isn't a fair comparison given the age and coating differences. Anyhow, any knowledge you can share is, as always, appreciated. Cheers.</blockquote>