rokinon 16mm vs rokinon 14mm

[redlazer]

I'm looking for a camera to shoot stars and shoot large group shots. I have a canon 7d and I'm not sure about what one will be best the 14mm or the 16mm. The 16mm is newer, for crop sensor cameras, metal barrel, only a little more expensive, detachable hood, uses 77mm filters, supposed to be very sharp corner to corner, but not that many reviews. The 14mm has great reviews, is older, wider, no detachable hood, and no filters. I have the canon kit lense 18-55 and I find I have to back up a long way to get my military unit pics so I'm just nervies the 16mm will not be wide enough. I thought about getting the canon 10-18mm but the I wouldn't have the cash for a long time to get the other lense. So I'm kind of looking for a lense to cover both areas. For a walk around lense I tend to use a canon 50mm f1.4 or the canon 70-200 f4. Thanks for any help.