So I've searched the forums and the FAQs, but I can't seem to find a direct answer to my question. I have been researching my next lens, and am finding that there are a few lenses with incredible focal range that are around the same price as those with a small range. I guess I'm wondering what I'd be giving up when going to a camera with a longer zoom range over one with a small, defined range. I should add that I'd like to spend $500-700ish.
I own a 50D. I plan to use this lens to shoot composed Architectural shots, primarily exterior, as well as use it in candid family settings also. I have a Tamron 10-24mm that I will use for interiors. I'm currently using the 18-55mm kit lens, but I find that the range is limited if I want to zoom in to highlight a certain detail of a building (detailed connection of an aluminum sunshade, or something of the like). I also have a Tamron 70-300 non IS which I don't care much for (will eventually replace), and a 50mm f/1.8. I tend to shoot wide, so I would like a 17-18mm as my focal beginning. I like to do a lot of night shooting as well, which may be a factor in my choice.
For instance, I've been looking into the Tamron 18-270mm Di II VC f/3.5-6.3. From the reviews I've been reading that the image quality is good despite a bit of chromatic aberration.
Other lenses I'm considering:
Tamron 17-50 f/2.8
I'm open to suggestions.
Does anyone have links to information about focal range versus sacrifices in image quality articles or anything like that? Honestly, I'm a bit overwhelmed by all the different options that I am able to pick from. Any help that members of this learned forum can provide me with would be very appreciated.