Long lens...

[lmontes1974]

If you need only one: 200-600 f 5.6-6.3 or 100-400 f 4.5 - 5.6?

[TrekRover]

For me personally, it was the 200-600, for the maximum focal length reach. The reason and way I built my gear line up was due to what I had first and to cover all focal lengths without overlap. I started with 70-200, then 24-70, then 200-600, then 12-24mm to essentially cover the spectrum of 12-600mm adding on the 2.0x TC I can cover up to 1200mm add on crop I think ~1600mm

[lmontes1974]

For me personally, it was the 200-600, for the maximum focal length reach. The reason and way I built my gear line up was due to what I had first and to cover all focal lengths without overlap. I started with 70-200, then 24-70, then 200-600, then 12-24mm to essentially cover the spectrum of 12-600mm adding on the 2.0x TC I can cover up to 1200mm add on crop I think ~1600mm

and in terms of quality image?

[TrekRover]

and in terms of quality image?

I've never used the 100-400 so I can't offer a comparison, but the 200-600 is fast and it has pretty good image quality. Here are some sample images.

 

[jb]

The 100-400 and 200-600 are very different lenses in use.  So it really depends on what subjects you're shooting and how you expect to carry either.  The 100-400 carries exactly like a 70-200.  Same size and weight.  Fits in the same bags.  Easily shoulder carried.  The 200-600 is very different to carry and use.  It's size is more akin to a supertele like the 600 f4 due to the constant length.  You need a much longer bag to carry the 200-600.  Hiking or simply walking around with it requires a different approach.  It's nearly a kilo heavier than the 100-400.  I can hand hold the 100-400 all day (and I do).  I want a monopod when using the 200-600.

[tonygale]

Depends on what you are shooting, they are both excellent. For wildlife I would say the 200-600, for a general long zoom the 100-400

#FE 100-400mm F4.5-5.6 GM OSS #FE 200-600mm F5.6-6.3 G OSS 

[glb]

for me the 100-400 with 1.4 converter. the 200-600 although a great lens it is to long. I do most of my pictures off my bicycle and with the cotton carry and the lens hanging in front of me my knees hit the lens every time I pedal  

[CuriousBirder]

Are you considering getting rid of one, getting one, or just have a general interest regarding them? I have both. I bought the 100-400 while my 200-600 was being repaired. Most of the time, the 200-600 wins. When a bird lets me get close, I prefer the 100-400 as it allows you to get closer. It's overall a better lens when doing macro. I find the AF to be faster and it is lighter which makes following faster objects easier. Hummingbirds allow me to get close, so the 200-600 is ok most of the time. A 600 prime in those cases would be worthless to me but great when dealing with birds further away.

[IraBlock]

The 200-600 is a nice lens, but it is big lens. If you are on safari and working out of a vehicle or shooting sports in one place it is not a problem. But if you are moving around a lot it can start to weigh you down. My solution is the 100-400 and the Sony 1.4 tele extender. It is a great portable solution