Excerpt: Let me preface this by saying - I think a 28mm is an essential in a photographer's toolkit. Much like a carpenter has a hammer, a screwdriver, etc, a photographer should have a 28mm, 50mm, and if you're lucky a wide angle and zoom telephoto. That being said I am pretty indifferent about this lens. I thought it would replace my 17-40mm as my default lens but it's not quite wide enough.
Pros: Consistent Output, Easily Interchangeable, Fast / accurate auto-focus, Lightweight, Strong Construction
Excerpt: I really needed a low-light "standard" focal length for my T4i crop sensor. This lens was not the first one I ordered, but the Sigma 30mm 1.4. It wasn't so much the 2/3 stop of light but the rave reviews online. The Sigma could not focus at all even at 6 feet so I ordered the Sigma USB dock. I was able to get about 40% of the pictures to get in focus even at f/1.8--the rest were either front or rear focused. This was on a tripod with a stationary object.
Pros: Consistent Output, Durable, Easily Interchangeable, Fast / accurate auto-focus, Lightweight, Rugged, Strong Construction
Excerpt: I was looking to lighten my bag, and enable myself to use my 5DII when I'm just roaming the city, running errands, heading to/from work, or going out with friends ... just have it in my shoulder bag. This hits the mark. With the extra stops, it's also great in low-light situations. I do find the colors to be crisper on my two L lenses, but after a minute or two in post-editing, and I doubt anyone could ever tell the difference.
Pros: Consistent Output, Fast / accurate auto-focus, Lightweight, Nice Bokeh
Summary: Difficult to give an appropriate star rating for this lens. I would say 3.5 stars, definitely not more. Maybe I'm just spoiled though because I had the stellar Nikon 28mm f1.8G before switching to Canon. The Canon 28 f1.8, 50 f1.4 (and worse: f1.8) and 85 f1.8 are somewhat disappointing compared to Nikons newer "G" equivalents. Anyway - why do I only give 3.5 stars for THIS lens?
Summary: I've been using this lens almost exclusively since I got it on both a Digital Rebel XTi and an EOS 70D for both stills and video. You'll be hard pressed to get a better picture for the money that this lens costs. On an APS-C camera, this lens should be your standard prime lens that you use every day.
Excerpt: I have a Canon EOS Rebel T3i with a 1.6x crop factor, so 28mm is a normal lens for me. The 18–55mm kit zoom lens gives me all the wide-to-normal range and most of the aperture that I'd want, but it's so light, and the camera body is so heavy, that I can't use it for shooting from the waist (a street photography technique that I've employed for years), because the camera flips up and aims into the air.
Pros: Consistent Output, Easily Interchangeable, Strong Construction