One of things that many people have really enjoyed about video DSLRs are that in many circumstances you don’t need to use lights to film at night-time. The larger sensors combined with fast lenses and adjustable ISO mean that many situations which previously would have called for using lights can now be shot without them, which means without the need to carry about bulky equipment and power sources. Unfortunately this post isn’t about one of these occasions.
Filming fire spinning is basically a bit of a pain in the ass. There are two things you need to have relatively well exposed, the performer, and the fire. Although the fire props themselves kick out some light, the difference in brightness between the two tends to be far greater than a camera can cope with. Its one of those situations which really makes you appreciate how powerful and image processing tool the human eye is. Consequently without lights (even with a DSLR cranked up to 3200 ISO and a fast lens) you either get massively overexposed flames or massively underexposed performers. Either one of these means you’ve essentially failed. In the past when I’ve made fire based films with cameras like a Panasonic HVX200 I’ve needed a set of a few redheads (850w lights) to get enough light onto the performers while retaining some level of detail in the fire to make things work. For this shoot we had one redhead, and a 125w energy-saving lightbulb, and despite a near total lack of ambient light in the location, with the highlight tone priority function enabled the 550d coped pretty well, keeping a reasonable amount of detail in the flames and lighting the performers so their movements can be clearly seen.
One thing that was quite noticeable in post-production was that the image does tend to break up a bit if graded too heavily (probably because of the relatively high ISO used). The footage from a HVX stood up considerably better because of the extra colour information in the DVCPROHD codec, which has a lower resolution (720p) and higher bitrate (100mb/s) than the footage from the 550d (1080p and 44mb/s). But saying that, the DSLR’s superior low light capabilities meant that the footage didn’t need to be tampered with too heavily (although trying to make it look less like we’d hung a black sheet up did mean darkening some of the dark greys a bit).
Overall for what is a relatively cheap camera, the 550d footage held up really well in what is a really challenging set of circumstances to be shooting, there are few other situations where there’s such an enormous difference in luminance between different parts of the same image which need to be properly exposed, and once again the results are on a par if not better than what you get from ‘professional’ camcorders which cost several times as much as a 550d and a couple of lenses. This just underlined again to me what a game changer relatively cheap video DSLR’s are, they allow hobbyists/amateurs with a pretty minimal budget to create images which a couple opf years ago simply weren’t possibly without spending many thousands of pounds.