On Mon, 27 Oct 2003, John Francis wrote: > > When I last posted that live preview caused an increase in shutter > > lag I had a few people who doubted this. Here is the design book ... > > That just shows that some particular chip designs have this problem. > It doesn't mean that it's an inherent problem if you use CCD sensors. > > As I pointed out, CCD TV cameras work just fine, so it's obviously > possible to have a live-preview CCD SLR which adds less than 1/60 of > a second to the shutter lag - something you'd be hard put to detect.
I don't think that any manufacturers are building high resolution progressive scan CCDs with this characteristic though. > There may be other reasons (cost, power, ...) not to incorporate this > capability in a sensor designed to be used in a DSLR. But inasmuch > as there are proofs-by-example that it's possible, your assertion > that it can't be done seems to be on shaky ground I didn't say that it couldn't be done, I said that it isn't done at this point in time. The documented CCDs used for D-SLR markets don't have any high frame rate modes (or didn't when I last read the specifications). The ones used for P&S cameras can only do high frame rates (30fps or 60fps) when using a small percentage of the photosites on the CCD itself. alex
