Using the Canon 50mm f/1.8 with DSLRs

If you have a Canon 5d Mark II, then you probably already have a 50mm lens that you use frequently. If you instead have a DSLR with an ASP-C instead of a full frame sensor (like the Canon t3i or 7D), you may be unsure about getting one. The Canon 50mm f/1.8 is very affordable for it’s speed (compare to the 35mm f/2.0 at $376), but with the 1.6x crop factor on ASP-C cameras, it’s actually an 80mm lens, not a 50mm.

I’ve been using the 18-55mm kit lens on my Canon t3i for about a year, but finally decided to buy the 50mm f/1.8. After using it for a few weeks, here are the pros and cons I’ve seen as of yet. 

Pros

• Bokeh for your buck – if you want to crush your backgrounds into pretty little circles, you can’t do it cheaper than this.
• Low light – wide open, it performs beautifully in low light. You can easily shoot at night with just a few street lamps. If you do most of your shooting after dark (due to working during the day), even inside with lights, it’s an incredible improvement.
• Smooth focus for video – the only thing I have to compare this to is the 18-55mm kit lens, but there’s much less jitter when you’re trying to change focus in a shot. Also, the focus ring stays in one place, no moving in and out, which makes focusing a little easier, and means you could attach a follow focus.

Cons

• It’s a telephoto lens – that given, it’s been pretty usable as a general purpose lens so far. If you already enjoy shooting closer to the 55mm end of your 600D kit lens, then you probably won’t have a problem with it. You will have to move back further (1.5ft at minimum), which could introduce more shake, so keep that in mind.
• Difficult to keep in focus – when shooting with the aperture wide open, very little is in focus at any given time. So if you or your subjects are moving, it’s quite a task to keep them sharp, especially if you don’t have a follow focus (which I don’t). Also keep in mind that you simply can’t focus on anything closer than 1.5ft/0.45m. Magic Lantern has some great features to assist with focus (peaking and magnification – during recording), so you’ll definitely want to look into those.

All in all, my opinion is that for the money and the aperture, it’s worth buying as a second lens. I’ll try to keep this post updated as I shoot with it, and maybe discover more pros and cons.

I put together a quick test video using the 50mm with my Canon t3i – as you can see, it’s difficult to keep in focus. I had it set to f/1.8, at night, with just a few street lights.