Canon 500D I thought Id reply to what you said in an alternate thread here.
If lenses do not improve quality, then all professionals would be turning up to their shoots with kit lenses, and would save themself a lot of money.
A good point, but this doesnt happen for reasons other than image quality.
Professionals (a flimsy term
) require a high build quality as they use their lenses all the time. Plastic barrels and mounts just don't exude confidence and dont live up to the standards required by a full time photographer.
The autofocus speed is also an issue on kit models.
Also, if the maximum aperture is only f5.6, then this means they still need another lens for low light. If you just used a prime or bright zoom in the first place then this avoids carrying two lenses.
Doesnt mean much to me, but many people complain about the distortion of kit lenses.
Did I mention build quality?
These are the reasons the "pros" (at least the ones I know) dont use kit lenses. Ive never heard anybody who's opinion I respect in photography (sounds a bit harsh I know but didnt know how else to phrase it) complain about the image quality of the kit lens.
Hope ive helped