Intro
I am beginning this thread in a desperate attempt to escape the "Death of Alpha" thread. This was a response to a discussion of IS binoculars and a new IS monocular. Here are my usual disclaimers: I am fairly new to birding and my IS binoculars are older first generation Canon IS in 15x45 and 10x30. And of course ymmv.
IS Day or Night
For me IS is a big plus for astronomy and it hasn't proved as useful in birding so far. At night I can detect fainter stars and see more detail in faint extended objects using more magnification, but IS or a stable mount is necessary. The 10x30 is better than a handheld 7x50 or 10x50, and the 15x45 is considerably better than either the 10x30 IS or any non-IS handheld binocular I have tried.
Of course there are penalties to the 15x45 IS compared with lower power handheld: narrower field (4.5 degrees), clumsier pointing, it is heavy, focus is not particularly fast, close focus is not very close. Yet none of these are too difficult at night. For astronomy the binocular is always focused more or less at infinity, and while ir is heavy, I am neither wearing it nor carrying it around very much. It is either in my binocular chair or by my telescope.
During the day, the balance of advantages and disadvantages changes considerably. Stabilization does allow me to discern more detail, but birds are generally more active and much more prone to rapid motion than most astronomical objects (at least in terms of apparent activity and motion). I am also much more prone to action during the day. I am covering more ground, observing more from a standing position with no bracing, and shifting my view much more often. Because of this activity of both observer and observed, the issues mentioned above with field of view, handling, weight, and focus are more significant while birding. My daytime preference is 8x or 9x handheld then 10x30 IS, then 15x45 IS.
I am beginning this thread in a desperate attempt to escape the "Death of Alpha" thread. This was a response to a discussion of IS binoculars and a new IS monocular. Here are my usual disclaimers: I am fairly new to birding and my IS binoculars are older first generation Canon IS in 15x45 and 10x30. And of course ymmv.
IS Day or Night
For me IS is a big plus for astronomy and it hasn't proved as useful in birding so far. At night I can detect fainter stars and see more detail in faint extended objects using more magnification, but IS or a stable mount is necessary. The 10x30 is better than a handheld 7x50 or 10x50, and the 15x45 is considerably better than either the 10x30 IS or any non-IS handheld binocular I have tried.
Of course there are penalties to the 15x45 IS compared with lower power handheld: narrower field (4.5 degrees), clumsier pointing, it is heavy, focus is not particularly fast, close focus is not very close. Yet none of these are too difficult at night. For astronomy the binocular is always focused more or less at infinity, and while ir is heavy, I am neither wearing it nor carrying it around very much. It is either in my binocular chair or by my telescope.
During the day, the balance of advantages and disadvantages changes considerably. Stabilization does allow me to discern more detail, but birds are generally more active and much more prone to rapid motion than most astronomical objects (at least in terms of apparent activity and motion). I am also much more prone to action during the day. I am covering more ground, observing more from a standing position with no bracing, and shifting my view much more often. Because of this activity of both observer and observed, the issues mentioned above with field of view, handling, weight, and focus are more significant while birding. My daytime preference is 8x or 9x handheld then 10x30 IS, then 15x45 IS.