I've taken the same image and tried to see how much of the food is in focus from front to back. I'm sure the waitress thought I was crazy, but hey, it's sushi. It's not like it's going to get cold! I focused all three images on the salmon skin rolls on the bottom left, and see how much depth of focus we can get by looking at the fruit in the middle, and the raw tuna and salmon on the top left. Alright, let's take a look at these pictures!
|shot with iPhone 4 with 1/3.2" sensor, 1/15th sec, F/2.8 @ ISO 100
|shot with Ricoh GR D IV with 1/1.7" sensor, 1/34th sec F/1.9 @ ISO 80
|shot with Fuji X100S with APS-C size sensor, 1/90th sec F/2 at ISO 400
Looking at all three pictures, I think the best balance of image quality and depth of field is the Ricoh GR D IV (middle image). At wide open, most of the food is in focus, reasonable dynamic range with just a little bit of blur near the very back. If I wanted everything in focus, I would just stop down to F/4.0. Although I shot the iPhone shot (top image) at less of an angle than the other two, the image still looks a bit flat and lacking a 3 dimensional feel, and I'm already getting a bit of highlight clipping. However, most of the food is in focus. Finally, the Fuji (last image) has the most Bokeh, but for a food shot, it's a bit too much. Notice that even the front of the roll is already out of focus. If I stopped down to F/5.6, most of the back would still be blurry, and I would have to crank up the ISO to get reasonable shutter speeds.
As mentioned on my Ricoh GR D IV review, the small 1/1.7" sensor is perfect for an EDC (every day carry) point and shoot camera, especially for those of us who like to take pictures of food and products. It doesn't have the resolving power of the larger APS-C sensor sized camera, but what we lose in resolution we gain back in greater depth of field. For those of us who have a Canon S series, Panasonic LX series, or a Ricoh GR D series camera, don't sell it once you get a Fuji X-100S, Nikon Coolpix A, Ricoh GR V, or a Leica X2. The highly versatile 1/1.7" sensor point and shoots are compact, feature packed, amazing macro, great depth of field (F/2.0 is approximately F/9 on a full frame), and very good image quality up to ISO 800.
If you want to know more about image sensor size, crop factor, and what APS-C really means, check out this link. Happy shooting, including food!