> >Wouldn't it be great if Nikon sold an 85mm f/1.8D AF DC? > > Why? At 1.8 and at portrait distance I will have quite a narrow DOF as it > is. My 85/1.8 and 135/2 are in use as prime lenses, I think the "DC" is a > gimmick myself. Defocus Control has little to do with the size of the DOF or how much you can "blow away" the background by opening the lens up. DC lenses allow you to alter bokeh, which the quality of the background blur, not the quantity. It lets you determine how smoothly out of focus objects in the background (and foreground) blend together. For example, imagine you are shooting a subject standing in front of some trees. Sky filtering through and reflecting from the leaves appears as a mass of light and dark fuzzy spots in the background. With my 105/2.8 at f2.8, those spots appear as hard edged circles. The background blur does not blend together smoothly, but looks contrasty and blocky. Out of focus lines tend to appear doubled up. If I had a 105/2 DC lens set to f2.8 with rear defocus, the same background would appear as a mass of soft edged spots, which blend together. I think this produces a much more pleasing and less distracting effect. Note that the DOF is the same on both lenses (105mm, f2.8) and the size of the blurry spots in the background is the same. The only difference is how smoothly the background blurs together. It can be a subtle effect, but in certain cases, it can make or break a picture. A smoothly blended background can give the appearance of being shot at a wider aperture, because wider apertures also tend to blur backgrounds more smoothly. Of course, if you only shoot against a blank backdrop, background bokeh is irrelevant and DC lenses have no advantage. I tend to shoot most of my portraits with the AIS 85/2. It's hardly bigger than a 50mm lens, so it is very easy to carry and very discrete. It tends to produce chunky bokeh. If Nikon had an equivalent lens with softer or controllable bokeh (as in DC lenses), I would be *very* interested. Roland.
