Dazed767 From United States of America, joined May 1999, 5447 posts, RR: 53 Posted (9 years 1 month 3 weeks 4 days 17 hours ago) and read 2421 times:
I was looking to possibly get the 100-400mm IS L lens later this year, and I was looking at extenders as well, I can get the 1.4x and 2x for the same price. How much of a reduced quality difference is there between the two, if any? Thanks.
Patroni From Luxembourg, joined Aug 1999, 1403 posts, RR: 15 Reply 1, posted (9 years 1 month 3 weeks 4 days 16 hours ago) and read 2399 times:
last week a friend and I put my 1.4x II extender and his 100-400L together and used it on a tripod, taking photos mainly of light aircraft.
With an aperture of 5.6 at the top end (above 250mm), the 1.4x will set you back to F8, the 2x even to 9.5. In both cases you loose autofocus, which made handling quite difficult, given the fast movements of the aircraft.
I personally don't think that you will have much fun with the 100-400 with 2x extender,
1) because it becomes a very slow lens with F9.5 and
2) it will be quite difficult to handle with such a long effective focal length and manual focus.
Chris78cpr From United Kingdom, joined Feb 2004, 2813 posts, RR: 52 Reply 3, posted (9 years 1 month 3 weeks 4 days 15 hours ago) and read 2364 times:
Unless you have a pro 1series body you wont have Af with either convertors on the 100-400! If like me you are using it on the 10D then i really cant imagine u will need a convertor!!! I tried mine once and found it was way too long! My 1.4x is now reserved for my 70-200 and my 100-400 stays "stock"! Best way for it in terms of ease of use and quality!!!
5D2/7D/1D2(soon to be a 1Dx) 17-40L/24-105L/70-200F2.8L/100-400L/24F1.4LII/50F1.2L/85F1.2LII