Hey all, as I said in past posts I don't have a huge budget and I was only recently able to handle upgrading to a Canon 50D body to use with my previously purchased Tamron 18-270mm. Fun lens far as versatility is concerned, but I've been having some troubles in lower light (f/3.5-6.3), which I have often found myself in. Long story short, this is my first year doing my own taxes and well, I didn't even consider the tax refund check O_O. Fiscally I'm pretty conservative soo this amount lies outside of my budget as a decent surplus. I considered investing buut I feel maybe some new glass would be a different kind of investment and would definitely make me happy! Here's what I'm thinking: I primarily enjoy wide angle and portrait situations, so I'm looking at <= 100mm far as lenses are concerned. To that end, I've looked at three lenses in particular: Canon EF 28mm f/1.8 USM Canon EF 50mm f/1.4 USM -or- Canon EF 17-40mm f/4L USM *note* I consider the 50mm 1.4 rather than say the 85mm 1.8 due to comments about what effect my 1.6x body will have on it. please correct me if i'm mistaken. Now, whether I purchase the two primes or the L-series, i'm looking at relatively the same cost. I know what people say about L-series glass and their love and addiction to it, so I've been pretty settled on the 17-40mm but I keep reading reviews from individuals who criticize the sharpness of the lens as well as the f/4. Here are my concerns: I primarily find myself in lower-light situations. I did recently receive a promaster 7500 as a Christmas present but even with that my 18-270mm f/3.5-6.3 hasn't been that satisfactory. In another recent thread I read that the f/4 on that lens refers to the maximum aperture.. so then, what I do not yet understand, is f/4 "wide open" for this lens (B&H.com: f/Stop Range 4-22)? Since that seems to be the case, would the 50mm 1.8 and 28mm 1.4 lenses perform better in lower light than the 17-40mm f/4? I apologize if i missed something in previous posts. Things I understand/have considered: - the 28mm is obviously not going to be as wide as the L @17. - @40mm the L obviously wouldn't be equal to the 50mm prime. - i would be be loosing the range in between that the zoom offers. Questions: - The two primes, not being EF-S, would work on a Full Frame if i were able to upgrade to say a 5DmkII? ::buys lottery tickets:: Next, what are the opinions on the prime vs. zoom here? I can forsee people saying a zoom L will outperform non-L primes, but I believe its worth getting opinions. I'm by no means selling or marketing my photos but, I would like to get the best I can with this little fiscal surplus I am experiencing That's about it.. I hope I was specific enough in my questions and concerns, let me know if there are any questions. Again, these would be on a Canon 50D body.