Will this lens be good for natural lighting, outdoors, fashion photography?
If you are serious about fashion, you'd be better off with a different lens. What is your budget? The 28-135 is decent, but it is a slow lens for indoors. You'd be better off getting a tamron 28-70 f/2.8 I think for portrait work.
I would even go as far as to second the 50 1.4 prime, or even the 85mm 1.8.
I think for what you have listed as your primary uses, a fast lens is top of the list..
the 17-50 2.8 is an astounding lens, don't know if that is in your budget...
I already shoot with a 50 1.8 but all of my pictures come out really soft when i shoot with a wide aperture on Av.. any tips on keeping the sharpness?
Timely, I've been looking at the Canon 28-70 f/2.8 vs 28-70 f/2.8 tamron.
Serious coin diff, $1.3k Canon vs $450 tamron
So obviously there is a diff to justify $800 more for the Canon.
For non-pro usage, home kids inside shots, etc, the tamron seems the value way to go.
http://www.bhphotovideo.com/bnh/con...sories&A=details&Q=&sku=284399&is=REG#reviews
Definitely the tamron a step up from the kit 18-55 lens.
Most lenses are at their sharpest around F8, so you're never going to get brilliant sharpness at f1.8. Also remember that DOF is very shallow with that wide an aperture, so you have to make sure your focus is flawless and that neither your camera nor your subject move between focus and shot.