> That is very strange. Do you have any explanation for why Canon uses 15cm? > > Is it because the front element of the EF 100mm f/2.8 macro is recessed?
I suspect that is the case. A lens designer will be responsible for the optical elements. Although the recessed front element is for me a real bonus - it does decrease the minimum working distance from the object we call a "lens". That said, it's one of the most effective lens hoods I've come across - almost never need additional shading. * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
