Archived posting to the Leica Users Group, 1996/05/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>I have a 100mm/f2.8 macro-R APO lens. I am thinking of either getting a 2X >APO teleconverter, or a 180mm/f3.4 -R APO lens. Weight vs larger f stop, >also 1:1 at 200mm 5.6. How does the 100 with the 2X APO compare with the >180 3.4, quality wise??? One MAJOR consideration that everyone seems to be forgetting about or not knowing about is that the 180mm f3.4 Apo lens was DESIGNED for OPTIMAL performance at wide open aperture meaning f3.4. Stopping down at any other f stop actually reduces the performance to equal the other two Leica 180mm lenses (180 f2.8 and the 180 f4). You should check to find out where the optimal performance is for the 100 f2.8 APO-Macro lens is as well to make the comparison. If in fact it is also at wide open apeture than you have a fair comparison. ADL