Canon 300mm f4 IS or Canon 400mm f5.6

Sam_swfc123 · #1 (**permalink**) 12-08-2010, 05:13 AM

Hello,
I was wondering which would be the best lens to get, either the Canon 300mm f4 IS with a 1.4 converter to make 420mm or buy a Canon 400mm f5.6.

Is there any links that are similar to this if there are I would love to have some links. Thank you.

Regards,
Sam Winslow

glsammy · #2 (**permalink**) 12-08-2010, 08:52 AM

Here's one:Canon 300mmf4 +x1.4 v 400mm f5.6

johnf3f · #3 (**permalink**) 12-08-2010, 11:13 PM

Can't speak for the 400 f5.6 as I have never used one - but I hear very good things about it!
I do, however have the 300 f4, and can heartily recomend it. The IS is the original version, groundbreaking in it's day but only OK now, also a number of people comment that the af is slow - it's not. If you use the focus limiter then it speeds up considerably, though still not as fast as the latest lenses. Note that at min focus distance this is an excellent closeup lens (not macro) but great for larger insects/flowers etc. I do get images where where it doesn't quite nail the subject, don't know if this is the lens or I have not set up my camera's af properly, but when it does this is a VERY good lens.
I like the colour it gives and love it's sharpness, this is now my normal carryabout lens.
My signature pic is an un-processed and viciously cropped shot of a Dragonfly at about 4-5 meters on a 1.3 crop body - not too bad?

PS. Forgot to mention I don't bother with either 1.4 or 2 x converters on this lens - I find it better to crop in most cases.

Sam_swfc123 · #4 (**permalink**) 13-08-2010, 06:50 AM

Thank you.

glsammy · #5 (**permalink**) 13-08-2010, 10:14 AM

Comparing the AF speed to the 400mm F5.6, I can assure you the 300mm is slow when used with a 1.4X TC. I've had both and in the end couldn't live with either the AF speed or the IS performance. Optically it's first class, no doubt about it. It all depends on your likely use. Birds in flight, the 400mm F5.6 wins easily. As an all round versatile lens, the 300mm F4 is back in the picture. Its minimum focus range is much better, making it good even down to Damselflies.

johnf3f · #6 (**permalink**) 20-08-2010, 08:37 PM

Quote:

Originally Posted by glsammy

Comparing the AF speed to the 400mm F5.6, I can assure you the 300mm is slow when used with a 1.4X TC. I've had both and in the end couldn't live with either the AF speed or the IS performance. Optically it's first class, no doubt about it. It all depends on your likely use. Birds in flight, the 400mm F5.6 wins easily. As an all round versatile lens, the 300mm F4 is back in the picture. Its minimum focus range is much better, making it good even down to Damselflies.

Suprised at you experience with the 300 f4. Whilst the af is not the fastest, if the focus limiter is used it's not shabby compared to my other 4 "L" lenses. The IS is (I believe) the earliest version and is a bit clunky by current standards and has trouble with fast moving subjects, though is a considerable advantage on less speedy and static subjects, but most people turn is off for bif etc.
I would say that my 300 did rather well on the Welsh Red Kites and yes I had forgotten to set the focus limiter and turn off the is! This is one of the sharpest lens I have - though the 100 macro shades it - JUST!

I hear VERY good things about the 400 f5.6 and rather fancy one but it is far less versatile.

P.S. I don't bother much with the converters as it's usually better to crop on my camera.