Following the lens recommendations of both my HDSLR patron saints, Messrs Leitner and Bloom, I went a head and purchased a Sigma 30mm f/1.4 for a few reasons:
- It’s fast. And I mean really fast, at least of paupers like myself who can’t afford red-ringed pieces of glass like other luminaries. At f/1.4, you can comfortably shoot indoors, often without special lighting if you bump up the ISO a bit. Great!
- It’s affordable. Well, compared to L glass and Zeiss primes anyway..it’s not as cheap as old MF glass off eBay, which can be had for less than $100, but I still think it delivers excellent image quality for the price tag.
- It’s a standard lens, at least on a crop sensor camera like the 60D. For some reason, I like the fact that you can’t zoom with this lens, as it makes you think more about composition (unless you’re so lazy that you’ll just snap it anyway and hope for the best). The field of view is similar to that of the human eye in that it more or less shows what you see. Photographers have only had this kind of lens (the 35mm film equivalent of a 50mm lens) available for decades last century and I’m planning on following in their footsteps, no matter how clumsily!
However, it’s not without its drawbacks. The biggest one for video would have to be that it is an AF lens. Drawback, you say? Yes, it is for video on cameras like the 60D, on which you have to rely on manual focus most of the time.
Manual focus lenses have a lot more leeway between focus distances (sometimes called ‘ long focus throw’ I think but don’t quote me on that!). These days, few people rely on MF and therefore only few manufacturers still build lenses without AF (a few notable exceptions are German lens makers extraordinaires Carl Zeiss and the Korean Samyang (which also sells as Opteka, Rokinon, Bower and half a dozen other names).
So what about the Sigma?
Well, it’s a great stills lens. AF is fast and, at least on my copy, accurate. However, when I try to manually focus during video I often ‘jump’ past the focus point. It takes only the smallest adjustment to (a millimetre turn sometimes) to completely render your subject OOF (out-of-focus), especially wide open (at f/1.4). At the lens’ MFD (minimum focus distance) of 40cm, this equates to a tiny depth of field of 9mm! Doesn’t give you much room to play with…
PS: I have a handy little iPhone app called the Simple DoF Calculator which does the same as any other web-based DoF calculator, except quickly and on my phone. 🙂
Also, it’s an APS-C lens only. If I ever decide to move to full-frame in the very, very distant future, I won’t be able to use the Sigma on the 5DMk3.
All things considered, though, I think that this lens will remain permanently attached to my camera for a long time to come. Well, at least until I get my hands on the Tokina 11-16mm ;P
Update: I just had a play with a Tamron 17-50mm f/2.8 today (the non-VC version) which was my alternative to the Sigma. While it’s a nice lens, I’m glad I went with the Sigma instead. It’s quieter and a full two stops faster, which in my book is worth a lot. The focusing ring had basically no resistance which was a huge change from the Sigma…strange at first but actually quite pleasant. It was also a huge contrast from the zoom ring which almost refused to budge. Nice lens and a good alternative to Canon’s super-expensive 17-55mm f/2.8 but yeah, go the Sigma instead 🙂