This is a little phrase that my daughter brought home from school. If that's the worst thing she ever says, I can live with that.

As I mentioned in the Feb. 10 entry, the first roll I shot after getting the camera back was with a roll of Kodak black and white infrared (HIE). It's a great film, and one of the few special-purpose emulsions that Kodak hasn't killed off ... yet.

There was a small problem with this plan. I don't have red or infrared filters for either the 25mm Biogon or the 50mm Planar. However, I did have a 40mm Sonnar that I bought several years ago as part of the Rollei 35 RF package. When I bought the camera, I also bought a B+W deep-red filter specifically to use with infrared.

The Sonnar is a Leica thread mount (LTM) lens that comes with its own LTM-to-M adapter. On the Rollei 35 RF, which is a Cosina Voigtlander Bessa-R2 clone, the framelines are user selectable via a top mounted lever. On the Zeiss Ikon, the Sonnar brings up the 50mm frame lines. I'd rather have the 35mm lines come up, because I think those frame lines are closer to the actual lens. Perhaps in the future, I'll buy another LTM adapter for this.

The Sonnar takes on a whole different personality mounted to the Zeiss Ikon. For one thing, I find that the focusing action of the lens is a bit smoother than it was on the Rollei. That doesn't seem to make sense, but I find the lens more usable on the Zeiss Ikon. The second advantage is that the Zeiss Ikon can take advantage of the close-focusing abilities of the lens. Both the lens and body close focus to 0.7 meters. The rangefinder on the Rollei (and the Leica M3) disengage at 0.8 meters. This might not seem like much of a difference, but if you're going for a tight shot, it means you can't precisely focus closer than 0.8 meters.

I've always liked this Sonnar. It shows some barrel distortion at close distances, so keep this in mind when photographing brick walls or rectangular objects. For most purposes, I doubt you'll notice this. The lens is very sharp, and the depth of field eliminates the need to refocus for infrared.

The Sonnar is a heavy lens – much heavier than you would expect for this somewhat compact lens, and I would guess that it uses a significant amount of brass and steel. It's marked "Made in Germany." Focusing is accomplished with the small tab. I've never been a fan of tabbed lenses, and this one won't change my opinion. I didn't have any problems focusing the lens, although for me a traditional focusing ring is easier and quicker to focus more accurately. The larger size of the Zeiss Ikon body matches well with the Sonnar.

I had to keep reminding myself of the framelines, and I used the frameline preview lever so I could approximate the field of view. As I mentioned, a different lens adapter will work much better.