Additional note:
This lens has an angle of view of 180 degrees in all directions (horizontal, vertical and diagonal), or 360 degrees along the edge. The only way to use dark IR filters with this lens is by mounting the filter behind the shutter, between the film rails. A story about how this lens was converted from Pentax-K to EOS can be found on my Main Page.

If you have any question, remark, comment, want to share some philosophy or just want to express your opinion about these pages, feel free to send email to: w.j.markerink @ a1.nl