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Please note that this article dates a few years back and that it's not been updated since. The theoretical informations it contains can be applied to current cameras. Using hyperfocal with the G3A lot of people complain about the G3's autofocus performance in low light situations or with fast moving subjects like kids. The G3 is not a point and shoot camera. It requires knowledge and efforts from the photographer. The good news is that by using a bit of knowledge in photography theory, you can turn your G3 into a really mean machine, performing better than any P&S. The trick is to use a photography technique based on hyperfocal. What's hyperfocal? Here are two quotes that describe it pretty well: When the lens is focused on the hyperfocal distance, the depth of field extends from half the hyperfocal distance to infinity. (Photography, Phil Davis, 1972.) I found these quotes on a wonderful web site that covers pretty much everything you'd want to know on depth of field and hyperfocal. It has a useful online DOF calculator and also one you can install on your PC to print your own charts. http://dfleming.ameranet.com/ How to set your G3 I have created a custom preset for parties and other situations where I can't rely on or wait for the G3's autofocus. To learn how to use custom presets on your G3, check your manual on page 109. I used the online DOF calculator (see link above) to determine the perfect DOF settings for my needs. I ended up using settings that are not true hyperfocal since DOF doesn't reach infinity. I did that because I wanted to gain a few inches in front of the focus distance and since this preset is intended primarily for indoor situations, I don't need infinity. Here are my settings: It's important to set the focus distance manually. Setting to 5 feet with aperture f/5.6 will give you a depth of field ranging from 2.5 to 724 feet. This should cover most of your needs! You must use a focal lenght of 7.2mm (full zoom out) for this to work. If you zoom in, your DOF will shrink dramatically. Use your feet to zoom in or out. This shouldn't be a problem in normal size rooms. In parties, I usually find myself within 10 feet from my subjects and portraits are often taken from shorter distances. An excellent side effect from using manual focus is that your G3 will be very fast. All the shutter lag caused by the autofocus system is gone. The camera only has to determine shutter speed. You only have to care about composition and shoot. That's really fast and it's better than any P&S. Note: as you have probably noticed, this preset requires more light than what would be available in most indoor situations. I created it that way because I always use my 420ex flash for that type of work. If you want to work with avalable light, you should use higher ISO settings and maybe use a larger aperture but higher ISO means more noise and a larger aperture reduces DOF. Note on internal flash: |