Another non-finder snap by P&S DC. Since I am doing a lot of non-finder street quick snap, the focusing speed of the DC is very important. I was and still using the Fujifilm F10, and the response time is quite good.
For non finder snaps, the old masters will use zone focusing (or pre-focusing), ie. use relative small aperture eg. f/8, and pre-focus the lens to something like 3 or 4 meters, and most common subject will fall into the depth-of-field...... It sounds complicated, but it's actually very simple and basic photographic skill. This technique is getting lesser attentions, and I guess there are a few reasons behinds:
- Modern cameras have very fast and reliable AF system, so there is no need for zone-focusing (sorry for Pentax, the K20D + DA21 combo sometimes let me down in non-finder shots).
- The depth-of-field idea is actually an approximation: ie. the photo will 'looks' sharp for 'reasonable' viewing distance. Reasonable means you are looking at a 4R photo at around 25cm distance. So if you scale-up your photo 100% on screen, it's not sharp at all. Too bad most people do zoom-up on in computer to closely look at the photos, and zone focusing just don't work for this kind of critical scrutinization.
- MOST IMPORTANT REASON: most modern lenses do not have a depth-of-field scale... so there is no way to use the lenses for zone-focusing.
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