|Canon EOS 50D, EF 17-40mm f/4L USM at 40mm, f/5.6, 1/90 sec., ISO 400|
I was a bit bored on an overcast day earlier this week and decided to take a short walk with my 50D and 17-40mm f/4L lens. I haven't used this combination since I picked up my first full frame body a year and a half ago.
The combination results in a 27-64mm equivalent field of view with a minimum focusing distance of 11 inches. Normally for this range I would use my 5D Mark II body with the 24-70mm f.2.8L lens but I've been trying to decide if I should pick up a refurbished EOS 7D to replace the 50D - or not.
The 7D has significantly better autofocus and continuous shooting speed than the 50D and has upgraded weather sealing but image quality wise there isn't really a great difference. Since the 50D is now four years old and the 7D is three years old it might make the most sense to wait for a new crop sensor body to arrive. Or, wait for the price of the 5D Mark III to come down since that camera has a much improved autofocus system and a continuous shooting speed almost twice that of the Mark II.
Both the 5D Mark II and the 5D Mark III are full frame cameras and I've always felt comfortable having two identical cameras to use either together or having one as a backup. Back in the day, it was two Minolta X700 bodies. More recently two Canon EOS 50D bodies, then two EOS 5D bodies.
The question is, am I better off with two full frame bodies or one full frame and one crop sensor body? Absent winning the lottery, my lens collection is pretty much set for the foreseeable future. My four L series lenses, the 17-40mm f/4, 24-70mm f/2.8, 70-200mm f/2.8 and 300mm f/4 are the set I've settled on. Together with the 1.4X extender I've got everything from 17mm to 300mm (except 281mm to 299mm) and then 420 covered.
Now, if you factor in both a full frame body and a crop sensor body the options multiply. For instance, I could have a full frame body with the 17-40mm lens and a crop sensor body with the 24-70mm lens and have the equivalent of 17-112 all ready to go. I could also have a crop sensor body with the 17-40mm lens and a full frame body with the 70-200mm lens and have the equivalent of 27-200mm (except 65mm to 69mm) all ready to go. For scenics and nature I'd go with the former. For events like proms, weddings or conventions I'd go with the latter.
On the other hand, with two full frame bodies I can have 24-200mm available at all times, with wider or longer focal lengths as needed.