Some suggestions.
Lens filter:
You may want a UV, you may not. Most of the photographers I know use a protection filter for everyday use and have a stock of UV, polarizing, warming, neutral density, etc., filters to use as needed.
I prefer Hoya, if you can afford it, for the multi-coated protection filter. Yes, the multicoated filters are worth getting. If it's good enough for your lens, it's good enough for your filter.
I'm going to have to go with a cheaper brand for my selection of modification filters, but I like Hoya's stuff when I can afford it.
Lens brand/type:
Yes. Brand lenses are nice.
Yes. Brand lenses are overpriced.
Tamron, Tokina, and Sigma all make professional and pro-sumer quality lenses that perform just as good as or damn close to their brand name equivalents- at a fraction of the cost. There is great glass out there, and it doesn't have to come from Canon or Nikon.
For the price of one constant aperture brand name lens, you can get 2 lenses from another source. 2 *great* lenses, with constant apertures just like the brand name ones.
Film or digital lenses:
I suggest going with a film camera lens when you can. This is my personal take, mind you. It gives you flexibility in case you move to a full-frame sensor Canon later, or decide to use your lens on a 35mm body.
In addition, because of the 1.6x crop, you'll benefit in another way by using a film-based lens- your Canon will only be using the sharpest part of the lens for image information (the center). The edges of a film lens are essentially cropped out with a smaller than full-frame sensor, and the edges usually are softer than the center.
'Course, you don't have much of a choice but to use a digital-specific lens for your wide-angle end. I've seen incredible results from the Tokina 12-24 f4. Being in the $500 range, it's a great bargain and a well-built, quality lens.
What I use:
As my walkabout lens I use the Tamron 28-75 f2.8, and I love it. At $370, it just can't be beat for quality and versatility. The constant 2.8 comes in handy, since I love blurring out my backgrounds (and the bokeh with this lens is buttery smooth and quite pleasing).... bokeh is a Japanese word describing the quality of background blur, if I understand correctly.
Reference site:
dpreview.com/forums
Look, read, learn. Great resource, great people.
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