400/5.6

I know that everyone says that canon's 400/5.6 is a great birds in flight lens--but what about using it for sitting birds? Is it alright for that also or would the 100-400 be a better choice or still birds because of it's IS?

It is fine for sitting birds too.

It should be great for either one. Are you planning on using the lens exclusively for birds? If so, the 400 f/5.6 is probably the best out there.

The only thing i dont like about the 400 prime is its long MFD

Yes there are instances i've been close enough to birds to have MFD issues/worries with my 100-400...Your mileage may vary on this!

BirdBoy wrote in post #8371048
I know that everyone says that canon's 400/5.6 is a great birds in flight lens--but what about using it for sitting birds? Is it alright for that also or would the 100-400 be a better choice or still birds because of it's IS?

On a tripod, monopod or bean bag it'll give you more keepers and better IQ than anything else close to the price. If you really do need IS/OS you're better with the Sigma 150-500 OS or Canon 100-400 IS. You can use a tube to reduce the 'minimum focus distance'. Most interesting birds won't let you get close enough to have MFD be a concern IMO. Common garden birds or caged birds might be an issue. All depends.

The 400mm f/5.6L can provide...

The 400mm f/5.6L can provide great IQ and excellent AF. however, I prefer to use mine on a monopod or a tripod unless shooting birds in flight.

A shoulder pod (either commerically made or fabricated) can also help steady the lens if you cannot use a tripod or monopod....

I prefer the 100-400 for the still shots. I see very little IQ difference if any compared to the 400 5.6 on a tripod but the 1-4 does much better at slower shutter speeds handheld.

This *might* help:
https://photography-on-the.net/forum/showthre​ad.php?t=43436

It's a tough call, considering the way you put it. The biggest killer, to me, would be the minimum focus distance, if - and only if - you expect to get close enough to make it noticeable. (That is, under 15 feet.)

You can manage to be too close for the 400mm if you're a very good tracker, or if you set up in hides for small birds, or if you set up a feeder in your yard to attract bird. If you're too close for the 400mm to focus, it's not always so easy to throw a tube on fast enough. I wouldn't want to have a tube on at all times because one that is large enough to get you to 10 feet means you won't be able to get that bird that's 60 or 70 feet away. (Tubes reduce min focusing distance, but you also lose max focusing distance.)

There have been many times that I have missed a shot because I was too close with the 400mm. But not enough times for me to dismiss that lens - not by a long shot.

So you might want to consider other things to make a choice. That review I posted might help. I own both lenses, wrote that review years ago, and my opinions have not changed, so that review still lists my current feelings about both lenses.

Scottes wrote in post #8372167
This *might* help:
https://photography-on-the.net/forum/showthre​ad.php?t=43436

It's a tough call, considering the way you put it. The biggest killer, to me, would be the minimum focus distance, if - and only if - you expect to get close enough to make it noticeable. (That is, under 15 feet.)

You can manage to be too close for the 400mm if you're a very good tracker, or if you set up in hides for small birds, or if you set up a feeder in your yard to attract bird. If you're too close for the 400mm to focus, it's not always so easy to throw a tube on fast enough. I wouldn't want to have a tube on at all times because one that is large enough to get you to 10 feet means you won't be able to get that bird that's 60 or 70 feet away. (Tubes reduce min focusing distance, but you also lose max focusing distance.)

There have been many times that I have missed a shot because I was too close with the 400mm. But not enough times for me to dismiss that lens - not by a long shot.

So you might want to consider other things to make a choice. That review I posted might help. I own both lenses, wrote that review years ago, and my opinions have not changed, so that review still lists my current feelings about both lenses.

Good rundown

I agree with you, the 100-400 is definately weird to manually focus, I dont like the MF ring on it at all to be honest [Its probubly about the worst lens i have for MF..]