|
I struggled and struggled when I got my 70-200. I couldn't decide if I should spend the money on the f/2.8 or save $1,000 and go with the f/4. I went with saving money. I haven't been disappointed in that decision once.
Sure, faster is always better, but when you're dealing with "L" lenses, you're already dealing with the best, and depending on the body, if you pushed the ISO to 200 or 400, there is so little noise at either that using the f/4 probably wouldn't make a difference.
Now, I also agree with fnaqzna that you should always get the best you can afford, but I don't think for a second you'll be disappointed in the 17-40.
__________________
"I can normally tell how intelligent a man is by how stupid he thinks I am" - Cormac McCarthy, All The Pretty Horses
|