70-200 f4L and 1.4X, do you loose features?

[LexLuther]

After having read peoples questions regarding zooms, it seems to be a common idea that saving some money by going with the 70-200 F4L and adding a 1.4X extender is the best bang for the buck. Besides looking for more opinion on this topic, I was wondering if there were any downfalls to going this route?

I've read this http://consumer.usa.canon.com/ir/controller?act=ModelDetailAct&fcategoryid=154&mode lid=7462 and wonder if it just dumbs down the lens to something that will produce images similar to that of a 75-300? (not that I think the 75-300 is junk, I'm a newb.)

And considering I have the 18-55mm, 50mmf1.8 (and would like to get the 70-200f4L) for my Digital Rebel currently, what nice lens could I get to fill in the gap, or perhaps completely replace the 18-55 altogether? The more I use my 50mm, the more I realize how much I need the 18mm on the stock lens. Price would also be of concern to me, I'd like to stay away from $1000+ lenses.

I was thinking of the 28-135IS, but maybe that's just too much overlap?

Any opinons or ideas would be greatly appreciated.

[drisley]

The max aperture will change one stop to f5.6, which isnt too bad for outdoor sports.
As far as image quality, you wont lose any (well not that I'be been able to see at CLOSE inspections of images I've taken with the 135F2L and 1.4x extender).

[CoolToolGuy]

I have the 70-200 f4L, and I absolutely love it. I also have the 1.4x TC, and I have not yet seen significant degradation in the images. I think if you need to or want to do post-processing (cropping, exposure, etc) you may see it, but they seem fine out of the camera.

As for a lens to fill in: I have the 24-70 L, but it is big and heavy. I had the 28-135 IS, but I sold it because I kept the 24-70 on the camera most of the time. You may want to consider the new EF-S 17-85 IS lens that will be out next month. It gives you the equivalent of a 28-135 on a full-frame, and it appears to be somewhat compact. The real 28-135 will overlap the 70-200, but the wide end is not really a wide angle at an equivalent 45mm. The 24-70 is a nice lens, but it costs $1200. The 17-85 IS is supposed to be around $600. Quite a difference.

Have Fun,