Hello,
I've been following the list for quite a while, now it's time to join in, in spite of the tons of email this will bring along...
I got to Pentax about a year ago, when I purchased my first SLR remembering some words in favor of Pentax from an aunt of mine, who was a photographer in her younger years. Let it be hazard or fate, I didn't regret this decision by now.
Now for my question: I've taken a lot of photos with my LX over the past year, sometimes feeling slightly unsatisfied with sharpness, especially at wide apertures. As I understand this isn't necessarily an issue ;-) I thought it was in perfect condition as it had been twice to Pentax for repair. Nevertheless, after finding an offer for an MZ-S I couldn't resist to I was astonished about the achieved sharpness in some pictures taken at wide aperture. This made me think. I've been using the just mentioned lovely combination of LX with SE-60 screen, so I thought it might be a question of focussing. So I made a few test shots with a split image screen to be completely sure where I do focus at, focussing a certain point of a folding rule laid diagonylly across the image. This to be able to determine the error in focus, if there was any. I'm sorry I can't show any pictures by now because I have to set my scanner first, my computer gear is somewhat under construction. I did the same shots, equally with a set of my widest primes at widest aperture to achieve smallest DOF, using my Super A body that also features a split image screen. Now the result surprised me in a way I didn't expect. All shots taken with 50mm lenses were in focus taken with the Super A, and focus was in front of the point I had focussed to with the LX. But the other two fast primes I own, A 1.4/85 and FA 43, showed a different behaviour. Focus was behind the point with the Super A, and just about right with the LX. I had read that the 85 would focus behind the focus plane but could't imagine how this should work. Now I see that it does, somehow. What I don't understand is why the 43 acts the same way, as it's focal length is shorter than 50mm. Focal length seems not to be an explanation.
I think my LX will meet Pentax again for a misaligned mirror, but first I wanted to ask if somebody can explain why focussing depends also on the lens used?
Thank you so far for your answers!
Cheers, Pancho
