Hi Bob
I'll be photographing drawings, you're welcome to have a look at
www.jonathanpauldavies.comYou're right in saying that APO lenses are recommended for this kind of work, again it just comes down to my budget. As I'm sure you're aware, there is a substantial difference in price between APO and non-APO lenses, the El-Nikkor 135 seems to be very highly rated, with excellent sharpness and little distortion, I also managed to pick one up new for a very good price. If things go better in the future, I may consider investing in a better lens.
I also acknowledge your point about keeping the planes aligned, this has been my biggest concern but I feel confident that I should be able to get it to work. I've been experimenting with things like microscope stages, and the kind of movements possible seem to be very stable. As far as the planes being parallel, most large format cameras don't look like they would demonstrate the kind of precision you're talking about. Granted, they can be adjusted with something like a Zig-Align but I'll have to wait and see when I have a working model how well aligned I can get it.
Choosing the Sigma was, in my opinion, absolutely the right choice for the work I'm doing. I've used a Canon in the past and while I've heard that in their newer models they're using a weaker AA filter I'll not go back unless there is a significant reason (true colour?). With all the Sigma's limitations, the difference in image quality was immediately obvious, I just don't think other manufacturers are aiming at this market.
Regards
Jonathan
