Shutter lag is the time it takes for the autofocus to lock and the image to be stored.

Autofocus makes up the majority of this time.

You can press the shutter button half-way down and this activates autofocus. When the action you want to photograph occurs, you press the shutter button the rest of the way down.
This will reduce you delay to approx. 0.1 second on most digital cameras.

If you just punch the button down, you will see the longest delay. The total lag can be one second on some cameras, or two seconds on older cameras.

The Olympus C770 is a fine camera but its overall lag is 0.8 second. The A95 overall lag is 0.6 second.

If you are looking for a long lens camera with short shutter lag, look at the Konica Minolta Z3. Total shutter lag is 0.2 second.
Konica Minolta has announced a Z5 model which is identical to the Z3 except it has 5 meg and a larger LCD.

Kodak has the DX7440 which has a total delay of 0.2 second. They have a new model coming out in a few months (Z730) which will be 5 megapixels.

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