"Robert" wrote in news:q0cmd.35592$V41.31572@attbi_s52:

I am finding out that all lenses are good, but some are better, cost
wise? most shots will not show up the defaults of the lower cost
lenses, only if blown up to 10x there is a difference, pros look at
this. 95% of the lower cost DSLRs users are not pros.

Agreed, to a point. Years ago when shooting with a Nikon F4 I was saddled
with a couple of Sigma zooms that providied me with some of the worst
optical quality I had seen since the original Minolta Maxxum optics. Got
rid of them and went with the real thing (Nikon)-Problems solved.

Currently I am shooting with a Canon 10D - My first foray into serious
digital shooting and I started with a 15-30mm f4 Sigma zoom. In a nutshell?
100% CRAP. Lens flare from hell at night, and a filter adapter that at the
15mm setting created a beautiful vignette affect.

I also had a Canon 70-300 zoom (Non-L series) that proved to be seriously
lacking in detail and contrast. I brought both back to the shop I got them
from, and got the Canon L 17-40 f4 and havent looked back since. Next
purchase will be a used L 200 f 2.8 from a friend of mine. I will no longer
look at Sigma and will be hard pressed to look at the other brands.