Hello all,
I have been reading various threads and have found that if a person has some astigmatism, a large exit pupil may magnify the problem. I have viewed some binoculars of the same maker and model of both 8x and 10x magnification and have found that the 10x looks clearer to me, but I am curious if this is because of the magnification or the smaller exit pupil.
I considering either a 10 x 43 or a 10 x 52 pair of binoculars (4.3 exit pupil verses a 10 x 52 exit pupil), I would like the larger objective lens for light gathering, but I am on the fence with this exit pupil thing, can anyone give me any advise on which binocular I should consider? Pros and cons.
By the way, what are the benefits of the larger objective lens? Does bigger give a clearer image? Is bigger better?
Thanks a whole lot
Objective diameter in mm divided by power equals exit pupil diameter in mm. Exit pupil size determines brightness, for the most part -- though other parts of the optical design contribute to brightness as well, e.g., lens coatings.
Astronomers will tell you that when the exit pupil becomes very small, human astigmatism no longer makes any difference. But from what I have learned, they are talking about very small exit pupils, maybe 1 mm or less. That wouldn't account for the additional clarity you are seeing in the 10x binocular. Not sure why that is.
I wear my glasses when I use binoculars, and my glasses correct for both nearsightedness and astigmatism.
[QUOTE=trashbird]Objective diameter in mm divided by power equals exit pupil diameter in mm. Exit pupil size determines brightness, for the most part -- though other parts of the optical design contribute to brightness as well, e.g., lens coatings.
Astronomers will tell you that when the exit pupil becomes very small, human astigmatism no longer makes any difference. But from what I have learned, they are talking about very small exit pupils, maybe 1 mm or less. That wouldn't account for the additional clarity you are seeing in the 10x binocular. Not sure why that is.
I wear my glasses when I use binoculars, and my glasses correct for both nearsightedness and astigmatism.[/QUOTE]
Thanks for the response, but do you know any advantage of a larger objective lens? Is the weight worth it?