300mm 2.8 for birding?

I am thinking of upgrading my 400mm f5.6 to the 300mm f2.8 IS. I know that the 300 is great with a 1.4 tc (420 at f4) But how good is it for birds with a 2x tc (600mm f5.6) There seems to be mixed reviews with this combo - anybody use one for birding with a 2x.
UPDATE: I have ruled out the heavier lens like 500f4 and 600f4 because I want a walkaround lens.

From what I've read and seen, the 300/2.8 is the best lens out there with a 2x TC. AF slows down a bit and IQ drops but it's still very good.

the 300 works great with the 2X and it is just an incredible lens in general. however, for birding, this lens wouldn't be my first choice. in birding, reach is everything and the longer the better. i use my 500 with 1.4x almost 99% of the time and the 2x when i need extra. i can tell you that even with the 2x, i still wish for more reach.

The 300 2.8L IS pairs extremely well with both of Canon's extenders. I have one of them on my 300 most of the time. I am very happy shooting with either combo. Most of the bad rap on the converters is from people using them on zoom lenses.

blonde wrote in post #3655847
the 300 works great with the 2X and it is just an incredible lens in general. however, for birding, this lens wouldn't be my first choice. in birding, reach is everything and the longer the better. i use my 500 with 1.4x almost 99% of the time and the 2x when i need extra. i can tell you that even with the 2x, i still wish for more reach.

Thanks for that blonde - forgot to mention that the 500 f4 and 600 f4 are out because of the weight, I need something to walk around with for long periods.

The 300 is going to be a bit much to hike with or hand hold for long periods of time.

you say that the 500 and 600 are out because of the weight, how about the price? if price is not an issue, i would take a long hard look at the 400 f4 DO (don't let all the internet talk scare you, people like Art Morris use that lens quite often and get stuning results)

I went through the same progression you are, started with a 400 5.6L, went to the 300 2.8L and I'm now shooting with and planning to stay with the 500 f/4L. The 300 2.8 and 500 f/4 are both a notch above the image quality of the impressive 400 5.6L, they both focus faster as well. In my experience the 300 2.8L + 1.4TC wide open beats the 400 5.6L wide open which is impressive, with the 2x TC the image quality is still good but improves stopped down and you do lose some autofocus speed but it's not bad.

The only problem with the 300 is that even with converters it's short for birding in my experience. As far as carrying lenses around I didn't really notice the extra weight of the 500 as I just throw it over my shoulder with a tripod/monopod or have it in my Kinesis backpack. I've never had any issues walking for miles with the 500, granted I'm in pretty decent shape. Where you will notice the weight difference is when you are shooting hand held with your arms extended, the 500 is still useable hand held just not for long periods. You should handle both if you can, neither are really walkaround lenses (not that I haven't done it) in general and you might find the weight difference not to be that big. When it comes to birds, reach is king.

I would agree with Tapeman about the bad press for the 2X. I don't have any problem using it on my primes but never goes near the zooms...IQ is not good enough. The 1.4X goes well with both.
I always seem to be too far from the birds though unless I stack the T/cons.
I would think that a 500 or 600 with a 1.4X is the affordable solution unless you only shoot on bright sunny days.
Bob

Roy C wrote in post #3655895
Thanks for that blonde - forgot to mention that the 500 f4 and 600 f4 are out because of the weight, I need something to walk around with for long periods.

That's exactly why I chose the 300 2.8 IS and a set of teleconverters. I'm very very happy with the setup. I compared the 300 2.8 with 1.4x to my 400 5.6 and the 300 was sharper (and a stop faster) at 420mm f4 than the 400 5.6 wide open. If you search threads I've started I'm sure you'll find the comparison. The quality drops off a bit with the 2x but it's still very good. I can walk around quite happily for several hours with the 300 and the weight is not a problem.

"300 2.8" and the word "walkaround" don't usually go together.

I would say hang on to the 400mm if you want a walkaround lens. For birds the 500mm and 600mm reign even though you've ruled them out. It's never a great idea to want to slap a 2XTC on your lens as a primary reason to buy it even though the 300 takes the 2X better than all other lenses. I have a 300,500 and 600 and I never touch the 300 for birds. With a 2X TC you will need a tripod anyway on the 300 2.8.

You need to think in these mm terms with TC's (on a 1 series you can af to f/8 with 500/600 anyway)

300mm 2.8 (300mm, 420mm, 600mm)
500mm f/4 (500mm, 700mm, 1000mm)
600mm f/4 (600mm, 840mm, 1200mm)

calicokat wrote in post #3655903
The 300 is going to be a bit much to hike with or hand hold for long periods of time.

Yeah, if you're a sissy like colikycat.:p

cosworth wrote in post #3656350
"300 2.8" and the word "walkaround" don't usually go together.

And a bigger sissy like Cosimoworth.

Take the word of the people here. They do not speak with fork tongue.

I bought the 300 f2.8. I love this lens. Did I say I love this lens?

But, alas, not for birding. It's too short. Plain and simple.

And if you're talking BIF, IMHO, you'll get better results with a Wimberley mount anyway, so weight isn't so much a factor.

MD "who's not quite as big a sissy as coliky and cos" JAK

Sissy who has a bunged elbow from walking around with walkaround lenses.

I tried birding with my 300. If I had a Mk.III and a 1.4 or 2x tcon then woo hoo. But no. It's a motorsport lens all day long in my part of the world. For others 300 is too short. Mind you I've used a 17-40 for motorsports.

400 5.6L is the minimum bird lens in my books. From there "up"

Just popped out into the gloom and took a shot with the 300 and 2X and 1.4X stacked....the 1.4 isn't reported in the EXIF.
Subject (a fucshia) was about 20m away, IS was on and a monopod used.
It may give you some idea what to expect...
Let me know if you want it sent and what file size you can handle

Bob