Some G15 travel pictures

Started Jul 30, 2013 | Discussions thread
Erik Ohlson
Erik Ohlson Forum Pro • Posts: 19,166
Re: Some G15 travel pictures

WillC2807 wrote:

Thank you all for your comments. To Zindanfel - all these pictures were taken in Program AE. I've noticed that the G15 has a preference for F2.8 or thereabouts in Program AE, unless (I think) it determines that it needs more DOF and hence a narrower aperture on one hand, or more light and a wider aperture (if possible) on the other.

Well, very likely not Depth of Field: with these very short [real, not "Equivalent"] focal length lenses, we already have huge DOF, just because of the focal length - the shorter the focal length, the better DOF.

And, yes, most Program Modes do tend to select wide apertures, for whatever reason the engineers choose.

But, there is a little-understood thing at work, here: Diffraction.

A physicist who posts on these forums tells us that when the physical opening of the lens gets down to about 3mm [1/8 inch] diffraction really starts to hurt sharpness, so I did some tests:

http://www.dpreview.com/forums/post/50567764

Please notice the foliage of the small trees near the center of the scenes - that's what diffraction does, so I now almost always use Aperture Mode and shoot at the widest aperture my camera has. This would be the same for, say, a Canon SX289, or any other brand.

Your G15, with it's 6.1mm, ƒ1.8 lens, comes in with a LARGER opening [3.4mm] so it's to a great extent capable of avoiding the worst of diffraction, good deal!

Shooting wide open, in bright light, I often run up against my camera's 1/2,000 second minimum shutter speed, so I use -E/V to compensate, or - in most cases the brightest area which is what gets overexposed, isn't all that important, anyway, usually your subject itself is not that bright.

I generally just trust the camera to choose the settings in most cases, unless there's a need to freeze movement in marginal light, in which case shutter priority often works better.

This is my first G series camera. I can see why many people like them. It seems to be very well designed.

Pictures removed for bandwidth, not criticism

-Erik

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'He who hesitates is not only lost - he's miles from the next Exit.'
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