After discussing what type of photos he was taking to come to this conclusion, it became obvious that he was hand-holding the camera and shooting at very slow shutter speeds. I explained to him that with so little DOF at F/1.9, he'd be hard pressed to get tack sharp focus of the tip of his model's nose if he introduced any shake or movement to the camera between the time he focused and depressed the shutter. I referred to a phrase I used years ago that in many cases "your depth of field can be no thicker than a pencil, so be careful how you shoot"
Thinking about this pencil analogy, I set-up a photo to illustrate how narrow DOF can be. The image below of a 25 year old handmade Swiss doll and a No 2 Mongol pencil was shot with my K-x using the single focus point with the FA 43mm Limited lens at f/1.9, ISO 200 with an exposure of 1/200 sec. I used a tripod to prevent any camera shake. I focused the lens on the pencil at the top by its eraser. By examining the image, my friend was able to see just how narrow the DOF was with this lens shot wide-open.
I thought this sample might be of interest to other Pentaxians and therefore posted it here, along with the approximate DOF calculation for this photo, provided by www.dofmaster.com. I also was interested to see how the background blur (bokeh) of this lens looked with my K-x. Based on printing this file at 13x19 on Velvet Fine Art paper with my Epson 4000 printer, I have to say this simple test image reproduces very nicely. The Swiss Doll image was shot in RAW and processed into a jpeg for posting on blogger using Adobe Camera Raw 5.5 and PhotoShop CS4. Click on the thumbnail to see a larger image.
