Ashtray re-visited

Today I was back on the same cafe seat where I took the original photo, this time with the G11, so I decided to investigate his suggestion.

First, here is the original image shot with the Pentax 200mm on a K7 APS-C body, no cropping this time and no adjustments

Now here is the full frame shot taken with the G11 from the same spot, at full telephoto zoom. The ashtray seems to have moved during the intervening period but I didn't bother rearranging it.

There are two immediate differences. The field of view is much wider, and the DOF is much deeper. This is because the G11's 140mm can't compete with the Pentax's 300mm (35mm full frame equivalents), the max aperture on the G11 at full telephoto is only f4.5 as opposed to f2.8 and, tellingly, the physically small sensor you get on cameras like the G11 inherently gives much less apparent DOF than larger ones at the same aperture.

You could achieve a similar effect by moving closer with the G11, and shooting at a wider angle at f2.8, but you would include much more of the background and still wouldn't get the same narrow depth of field. Meaning that you couldn't achieve the desired effect of isolating the subject.

So why use a fast telephoto? To isolate the subject, both with shallow depth of field and limiting the background. To "get close" to objects that are otherwise inaccessible - not necessarily far away. (not here of course, but we're just doing a for-example).

Before anyone suggests that I'm knocking the G11, far from it. I love the little camera and carry it all the time. Image quality is excellent and operation provides many of the options expected from a dSLR in an intuitive, un-fussy interface. (buttons and dials - not menus). We can crop that full frame image to a similar field of view as the Pentax, and although the DOF is still not as shallow (you can for example see the handles on the far away box) the clarity is impressive for such a small crop.