@TCampbell wrote:
A slight wide-angle lens works well on cars because it exagerates the size. When shooting from the front or back, the car appears longer. When shooting the interior, the interior seems roomier, etc. You can use a wide angle not just to be "wide" but because of it's property of extending "depth" it makes long objects seem longer as it stretches the depth of the scene. [links removed per forum guidelines]
You could do this with the kit 18-55mm lens (assuming you have this lens). You could go really wide by getting something like the EF-S 10-22mm but I'm not sure you'd really need the extra wide angles below 18mm that the kit lens would already provide. I'm thinking you'll probably like the look at around 24mm range -- but that's a guess on my part.
I probably would _not_ use the 50mm lens for a car (but it's not like there are "rules" for this stuff.) It's just that a car is large and you'll have to walk back farther to get the whole car in frame when using the 50mm.
I think moderately wide (but not extremely wide) is a nice look for most car photos.
I probably would not actually "buy" a new lens until you're certain you like the look. If you're thinking of experiementing with a different focal length then you own, I'd suggest renting the lens for a few days to try out the look before buying.
You might also go browse through car photos on a well known site such as Flickr and then check the EXIF data to look at the focal length of the images you like.
If you’re not forced into one spot a fast prime like your 50mm is great for a couple reasons:
They’re sharper than cheap zooms
They’re fast, and the narrow depth of field can help reduce background distractions
They’re fast, and the lighting may not be great so you may need the speed
