How does this logic sound

I know, I know another lens topic....

I think I have it narrowed down.

---70-200 f/4 L
---1.4 x converter
---400 L
--- sigma 24-70 ex

For basic general shooting what do you think. Most of my lowlight stuff would be stills so I would be using a tripod so do you think I can get away with the f/4? I like that lens because I think it would be a better walk around lens since it is lighter than the 2.8. I may be taking some racing shots also but I think the f/4 or the 400 will be OK (or am I on crack)

I have thought about the Sigma 70-200 2.8 and 80-400 or even the 100-400L but I am not sold on those yet. Do you see any flaws in the logic???

Looks good to me, with maybe 1 remark.

The 400L is considered to be a BIF lens more than anything else, IOW, rather specialized. And as it is F/5.6, you can't (easily) use the converter on it. I would therefore recommend the 100-400 L, instead of the 400 L and converter. It is a little more difficult to do BIF with the 100-400L, but it will serve at all other focal lengths too, and is great for racing and other sports.

Kind regards, Wim

Strick,
Not Logical, as I don't know what camera you have or what type of photography you like.
I personally (like wimg suggestion) would rather have the 100-400 IS f/4.5-5.6L as it give more options and much easier hand held possibilities.
Give us some more info as it will be easier to give some suggestions

wimg wrote in post #3798439
Looks good to me, with maybe 1 remark.

The 400L is considered to be a BIF lens more than anything else, IOW, rather specialized. And as it is F/5.6, you can't (easily) use the converter on it. I would therefore recommend the 100-400 L, instead of the 400 L and converter. It is a little more difficult to do BIF with the 100-400L, but it will serve at all other focal lengths too, and is great for racing and other sports.

Kind regards, Wim

What, if I may ask, does BIF mean? I don't find it in the sticky list of abbreviations.

Thanks.

BIF = Bird In Flight