While searching for new binoculars, I became enamoured with the Swarovski SLC's. Specifically, I am choosing between the 8x30's, the 7x42's and the 10x42's. Low light viewing will be a consideration from time to time, but weight is always a concern with something that hangs around my neck.
Before I jumped to the twilight / exit pupil based decision I wanted to ask a question of experienced viewers. Does the better low light performance of the 42mm's significantly offset normal hand vibration (I don't shake any more than average)? In other words, will human limitations negate the larger lenses?
Thanks!
Hi, engineer! A warm welcome to you from all of us on staff here at BirdForum!
I've had my B&L's 10x42 Elites for years and used them under all kinds of conditions, including on pelagic trips. Love 'em. Can't say I've ever noticed more shake with them over other powers, even on a heaving boat deck with engine vibration, but I could be particularly oblivious. 
[QUOTE=engineer]While searching for new binoculars, I became enamoured with the Swarovski SLC's. Specifically, I am choosing between the 8x30's, the 7x42's and the 10x42's. Low light viewing will be a consideration from time to time, but weight is always a concern with something that hangs around my neck.
Before I jumped to the twilight / exit pupil based decision I wanted to ask a question of experienced viewers. Does the better low light performance of the 42mm's significantly offset normal hand vibration (I don't shake any more than average)? In other words, will human limitations negate the larger lenses?
Thanks![/QUOTE]
Hello engineer,
I guess this question is designed for me, since I use several SLC binoculars, particularly the mid-sized 8x30 and the full-sized 10x42. I put "and" in italics because there is no way for me to get around that each is best suited for a different purpose. The 8x30 (mine is an older Mk II) is arguably the most versatile and presents the least burden to carry. My problem with it is not so much the brightness, since it works well in the mornings and into the evenings, but the distance it can cover. The 10x42 does that job much better, but it weights more. It is also better for situations when retinal size compensates for lack of light, such as hawk watching. Personally, I've never found a need for a 7x42, which provides a small image and actually weighs more that the 10x42.
From an engineering point of view the weight and balance of both instruments are well suited to hand held use. The 10x42 is noted to be outstanding in this respect, and high frequency angular motions are well damped (also see the BVD review by Steve Ingraham). To address your question specifically, however, human endurance for supporting that much weight for a long period of time does have limits, and so I've taken to using a monopod for extended viewing (see my FISMO equipment review). For the full-sized binocular I would emphasize the importance of the weight and balance of the 10x42, because 10x binoculars of lower weight, and not as well balanced, have mistakenly lead many to the conclusion they are difficult to hand hold. This one is not.
I'm sure there will no shortage of opinions.
Enjoy the view whatever you do,
Elkcub