Archived posting to the Leica Users Group, 2000/10/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Ah, a field curvature thread. I knew someone else would bring it up one day. I got dumped on last time I did it. :) Henning said that practice and experience are important in getting to know our lenses and I think this is the key to managing field curvature. I've learned that my 24/2.8 R lens has curvature to watch out for, and it goes back from the centre of the image as far as I can tell; 'convex' field curvature I suppose. eek! My 100 Apo Macro has a flat field, my 50/2's are slightly curved inwards (concave?). What does it all mean? I'm careful how I focus that 24 R lens. With my 50/2 M lens used up close, wide open and with subject's eyes way off center, I focus first, adjust the lens to a slightly closer focus and then recompose. This works pretty well. If I don't do this, the focal plane tends to end up slicing through a point just behind where I wanted it out there on the edge of the frame. With the R lens and the same kind of shot, I focus on the ground glass out at the edge. A Pop Photo article in 97(?) reported on the field curvature of the 50/2 and 50/2.8 M lenses. It's no big deal, but it's not imaginary either. Regards Rick Dykstra