I own a couple of binoculars (no alphas unfortunately) and I was wondering about the source of loss of contrast in binos. Can a "subalpha" have the same amount of contrast as an alpha?
What would make current alphas inherently superior in terms of contrast? Since contrast is not something that's objectively measured in reviews, I think there is a lot of subjectivity and biases about this concept.
There are many threads already about contrast, but it is often a term that includes two distinct phenomena in my opinion. On the one hand we have the light that creeps in from outside the FOV because of lack of proper baffling, that naturally affects the image of dark objects. And on the other hand, we can have very bright light present in the FOV that gets reflected many times on the different lenses before it enters our eyes, it can look like "ghost" images of the bright source, or just spread out in the whole FOV, affecting the image of dark subjects. I am interested in the latter, I believe it can manifest easily on cloudy days, since the white sky is much brighter (and occupies a significant fraction of the FOV) than tree silouettes, or dark objects or birds.
Common sense tells me that if we want to reduce this effect, we need better coatings and less optical elements. But this also means higher transmission, so do higher transmission binos have better contrast (of the latter type)? I can think of the Habicht that have the best Swaro coatings, and one configuration (7x42?) has very few optical elements, it makes sense that it has good contrast. But Ultravids are said to have good contrast too, and they don't have that high transmission (~88%). I guess "subalphas" like Zeiss's CHD and Nikon's MHG don't have more optical elements than NL Pures, Ultravids and SFs, and they have very close transmission, so I'd say they should have about the same contrast. Does this make sense? Am I missing something?
What would make current alphas inherently superior in terms of contrast? Since contrast is not something that's objectively measured in reviews, I think there is a lot of subjectivity and biases about this concept.
There are many threads already about contrast, but it is often a term that includes two distinct phenomena in my opinion. On the one hand we have the light that creeps in from outside the FOV because of lack of proper baffling, that naturally affects the image of dark objects. And on the other hand, we can have very bright light present in the FOV that gets reflected many times on the different lenses before it enters our eyes, it can look like "ghost" images of the bright source, or just spread out in the whole FOV, affecting the image of dark subjects. I am interested in the latter, I believe it can manifest easily on cloudy days, since the white sky is much brighter (and occupies a significant fraction of the FOV) than tree silouettes, or dark objects or birds.
Common sense tells me that if we want to reduce this effect, we need better coatings and less optical elements. But this also means higher transmission, so do higher transmission binos have better contrast (of the latter type)? I can think of the Habicht that have the best Swaro coatings, and one configuration (7x42?) has very few optical elements, it makes sense that it has good contrast. But Ultravids are said to have good contrast too, and they don't have that high transmission (~88%). I guess "subalphas" like Zeiss's CHD and Nikon's MHG don't have more optical elements than NL Pures, Ultravids and SFs, and they have very close transmission, so I'd say they should have about the same contrast. Does this make sense? Am I missing something?
