Scott F
Pug Life
Most lenses perform better when stopped down around couple stops from wide open, so if you have an f/4 zoom you'd need to be around f/8 to get optimum quality out of it, which would need a whole lot of light and probably would not be a shallow enough depth of field for what is typically desired from an interview. An f/1.4 lens, on the other hand, can be stopped down to f/2.8 or f/4 to get the best image out of it
I'm a bit confused/curious here. Can you clarify what you mean by "perform better", "optimum quality" and/or "best image"
What do you feel you are losing when a lens is wide open? Sharpness/focus? Quality of image? Colors? I don't usually shoot with my lenses fully open, unless it's an issue of not enough light.
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As for the OP's original question, I've always loved my Canon 24-70 2.8 for interviews with my Sony FS100. Will continue using it with my c100 but I don't have any real-world samples yet. And another vote for that mid-priced Canon 50mm. I think the 1.2 is $$overkill$$.
haha, those said rooms seem to be where I'm destined to shoot 96% of my interviews.Many rooms, such as offices, aren't that deep.