It might be true that a 42 mm binocular has slightly better angular resolution, a bigger exit pupil, higher relative brightness, a higher twilight factor, better light gathering and superior low light performance than a 32 mm, and I think angular resolution could be argued. The smaller aperture 32 mm and even 25 mm binoculars like the Zeiss Victory 8x25 are very sharp on-axis. But if you notice, all these things you mention are only important in LOW LIGHT. My point is and the point of the whole thread is I think for most birders that bird in the daytime like I do the 32 mm is the sweet spot for a birding binocular. The advantage of carrying a much smaller and lighter binocular is more significant than getting an extra 10 minutes of birding time at sunset, unless you are looking for Owls, and then you probably want a 8x56 or 10x56. We all have to decide based on how we use our binoculars what performance characteristics are more indispensable. My point of this thread is I think the newer 32 mm alpha binoculars like the Zeiss SF and Swarovski NL have improved to the point that unless you do a lot of low light birding, they are the ideal birding binoculars for most people. If somebody were to ask me. Dennis, I don't care about price and I bird mostly in the day and I hike quite a bit what binoculars would you recommend, I would answer get a Zeiss SF 8x32 or 10x32 or a Swarovski NL 8x32 or 10x32.
An 8x42 might give you 10 more minutes of viewing time versus a 10x42 right at total darkness, but any other time the 10x42 will outperform the 8x42 in lower light. A 10x42 will outperform an 8x42 a greater percentage of the time in lower light. That is why hunters almost always prefer a 10x42 over an 8x42, because they can count the buck's points in low light. Cabellas stocks mostly 10x42's for that reason because that is what hunters buy. As twilight goes to complete darkness, even an 8x56 or 7x42 isn't going to help you.
Andreas. Although you can argue that the pictures are not valid or the binoculars were dirty, or they had different transmission, the fact is you will see more detail with a 10x42 binocular in low light than an 8x42 binocular, given both binoculars are the same quality and have similar transmissions. You are trying to dodge the point of the post with your superfluous comments. If you don't believe in Twilight Factor or the fact that higher magnification aids low light performance in binoculars, try this. Right at dusk tonite find an object about 50 yards away which has some detail on it like a tree. Look at it to see how much detail you can see at 50 yards. Now move 25 yards closer to it and look at it again to see how much detail you can see. You will see MORE detail now because you are CLOSER to the tree. The surface area of the tree is bigger because you are closer to the tree and a greater percentage of the retina of your eyes which contain rods and cones are now viewing the tree. Rods are responsible for vision at low light levels (scotopic vision). Magnification in a binocular does the same thing! It moves you closer to the tree and in low light you will see more detail. A 10x will move you closer to the tree than an 8x, so you will see more detail with a 10x than you will with an 8x. A lot of people don't realize magnification aids your viewing in low light, just like aperture does.
That is true, but you have to decide if you really need the 72% increase in light gathering. For my birding which is mostly in daylight the new alpha 32 mm's are bright enough 99% of the time and 100% of the time they are a lot easier and convenient to carry than a bigger and heavier 42 mm. Plus, they have the advantage of a much larger FOV than most normal 42 mm binoculars outside of the alpha's. If you bird a LOT in low light then IMO that would be the only reason to get a 42 mm, and then I would choose a new alpha 42 mm like the NL or SF for the bigger FOV and better optics vbersus a normal 42 mm if price is not a consideration. That 72% increase in light gathering doesn't help you in the daytime. It might help you for 15 minutes at sunset and daybreak, and then the rest of the time you are lugging more weight around. If you compare a 32 mm NL to a 42 mm NL in daylight, you will see little to no difference in brightness or quality of view. That extra 10 mm of aperture is not needed most of the time. It is like having a 500 HP Corvette. Most of the time you don't need all that power until a Ferrari Enzo pulls up next to you at the stoplight, and the rest of the time you are using all that gas and paying extra auto insurance for that privilege of smoking a Ferrari IF he doesn't get the jump on you. I have a Kawasaki Z900 motorcycle for those times. It is much less expensive, but just as fast as the Corvette.
It is just personal preference, really. Some people feel it worth it to carry an 8x56 for the increase in light gathering and ease of eye placement. Have you tried the newer alpha 32 mm's? If you haven't, you might be surprised because there is no doubt you can't BREAK the laws of physics, but I think Swarovski and Zeiss have BENT them a little with these. They have closed the gap between a 32 mm and a 42 mm IMO.
Have you tried the new alpha 32 mm's? IMO, they are a game changer. Most birders don't need a 42 mm anymore with these suckers! Save the weight. Your view of the bird is just as good.
My point is most people tend to underestimate the value of magnification in low light, thinking EP is the only thing that is important. Sometime compare an 8x42 to a 10x42 in low light and try to read a license plate from distance. I have. It will surprise you. In fact as long as there is enough light to see, I would put a 10x42 up against an 8x56 for seeing detail especially at distance. It is true you can make out a wild boar easier with an 8x56 when it is dark, but if there is enough light to see you will be able to his tusks better with the 10x42. It is kind of like getting closer to that tree. When you get closer to something in the dark, you can see it better.
When is the point where you can no longer see enough?
Yes, as I stated in post 61, you asked me the same question in post 63, I haven`t seen any game changing, the newest "Alpha" 32`s are brilliant, no debate, they`re just not quite as brilliant as their 42mm siblings (IMHO), so I`m thinking they`re not the best birding binoculars right now, but I`m happy for anyone who does.Have you tried the new alpha 32 mm's? IMO, they are a game changer. Most birders don't need a 42 mm anymore with these suckers! Save the weight. Your view of the bird is just as good.
Good grief! Where do you live that you have stores that stock all those binos???
North central Idaho, Sportsmans
My point is for most people the new 32 mm alphas are the best overall binoculars when you consider optics, weight and size. IMO the 42 mm alpha's offer a small advantage in low light and if you are primarily using them in the daylight it is not worth carrying the extra weight for most people. You just have to decide for yourself if carrying a 42 mm in the field all day is worth that difference. It is just personal preference. In daylight, a 32 mm alpha offers an identical view to a 42 mm alpha with less weight and bulk.
You would be sacrificing a much larger FOV, more transparency, sharper edges and a much lighter and smaller binocular for a few extra minutes of observing time at sunset. 98% of the time when you are birding during the day the 32 mm alpha will give you a better view with a much wider FOV and superior transparency, and it will be much lighter and more compact to carry ALL day, except for the maybe fifteen minutes when the sun is going down the bigger 42 mm Conquest HD or Razor would be slightly brighter because of the bigger exit pupil. You have to decide, is that 15 minutes worth it to you?
