[WesternGuy]

I have read numerous articles on bbf but still a bit dubious as to its benefits. Something that bothers me is for instance one of the benefits is you can focus on a point were something is going to happen, then you are ready to take the shot the instant the action you want happens .... Say a kiss at a wedding, as there will be no delay in focusing .... But what about optical stabilisation .... It still needs to kick in or you can still end up with a blurred shot. So in this instance I cannot see the benefit and indeed the half press focus and wait for that kiss seems to be the better option. I am using a nikon d7000 with the bbf assigned to the af/ae lock button.

Iain, you have raised a very good point that I really never thought about that much. I do a lot of my shooting from a tripod so IS is not a consideration. I just checked one of my cameras (Canon 1D X) that uses BBF, with a 24-105 IS lens and I can hear the IS working as I move the camera around, so I am guessing that with this combination, at least, IS is working. I will definitely be more aware of this aspect of BBF in the future, even if it is just to check to see if it is working.

I think this also raises the question, for me at least, how does IS work in this situation because there are two situations for IS. The first is where the lens is stabilized and the second is where the camera itself provides the stabilization. I don't think the second situation is relevant because it pertains to P&S cameras and I am not sure that you can change the focus setup for these. (Please feel free to correct me on this if I am wrong.)

The other thing is how the stabilization relates to the focusing of the lens. Does the lens know how it was focused - shutter button or BBF? I don't know the answer to that question. If anyone does, then it would be nice to know. Personally, I don't think it does. From what I have read, it seems that IS kicks in once the focus has been obtained and attempts to maintain the focus. If this is the case, then the lens doesn't care how it reached focus, only that it has. This would then suggest that BBF has no affect on IS.

Any other thoughts on the subject would be welcome. In the meantime, I will try and see what I can learn from some of the pros that I know who use it.

WesternGuy