TIME-LAPSE AND SHUTTER COUNTS
Q I’ve really gotten into shooting time-lapse for some of my projects. While I’ve done so with regular video cameras, I’ve also been shooting more and more of it on SLRs. I like how small they are, and I don’t have to work as hard on rigging them and supplying them with power. I’ll admit it, I can be a bit of a perfectionist when it comes to shooting these, so I end up redoing them over and again. Thankfully, I’m not using film or I’d be broke, but while I can easily delete imagery that isn’t doing it for me, thoughts about camera wear and tear creep into my mind. Should I be concerned?
A As far as wear and tear goes, there’s the usual concern over wearing out mounts since you have to rig and unrig things. You also have environmental issues to think about, things like dirt, water and temperature. But these concerns shooting time-lapse are no different than the demands of shooting anything else.Unlike a video camera, however, using an SLR for time-lapse brings discussion of the shutter into the equation. A video camera’s shutter is electronic—but an SLR’s is mechanical, and it’s not a simple mechanism. Each capture of an image involves having the shutter open, close and then reset. That action happens quickly and relatively violently, and all those moving parts do wear down eventually.
You say that you reshoot a lot of your time-lapse, but you don’t mention the length of the time-lapse or, more specifically, the intervals you’re using. It might be worth seeing how much wear you’ve put on the shutter, factoring in length and interval. If you’re doing night skies, you might not accumulate many actuations. If you’re doing other scenes, you might be capturing an image every two seconds or shorter. Doing the math, two seconds is 1,800 shots an hour.
I’m not suggesting that you get out the microscope and look around inside, but rather that you discover how many times your shutter has been actuated. How do you do that? Some cameras allow you to read this information right on the back of the camera. For those cameras that don’t, this can be uncovered online (depending on your camera make and model) or with an application you already have, or even with a tool that can be downloaded to your computer.
Shutter count—the number of times the shutter has been actuated—is often stored in the metadata of each image file. SLRs use an Exchangeable Image File Format, or Exif, which provides a standard way of storing metadata. There are websites that will let you upload an image file that then will parse out the shutter information from the Exif metadata. Search for “shutter count.”
If your camera isn’t supported online, you may have a way of looking at the metadata with software you already own. Some of the built-in image apps have a Properties or Inspector function, allowing access to Exif data.
If these functions don’t drill down to find shutter count, you might be able to download an Exif application that can help you search for shutter count data in the Exif metadata. Look for “Exif tools,” but be aware that your camera model might reveal that information.
If you’re able to find out the shutter count of your camera, the obvious question is, how much is too much? Occasionally, shutter life is published by manufacturers, but generally speaking, is not. That range can be anywhere from 50,000 to 400,000 actuations, and is usually commensurate with the amount of money spent on the camera.
Does that mean after 50,000 actuations your shutter mechanism is going to self-destruct as if guided by the Impossible Mission Force? Probably not. There are several crowd-sourced online databases that show real-world experiences with shutter counts. Although not scientifically tested, they don’t reveal a whole host of cameras failing right after some sort of magic number.
How should you react to this? I guess if your camera is reaching its specified number of shutter actuations, you might think twice about traveling all the way to Jökulsárlón, Iceland, to do an iceberg time-lapse. Otherwise, since you’re already used to reshooting, then I’d say keep shooting.
READY (OR NOT) FOR MY CLOSE-UP!Q Normally, I work on things that will end up in HD or smaller. With cameras capturing 4K and beyond, can I consider taking advantage of that extra resolution when shooting? For example, can I shoot a wide shot and then just push in when editing?
A Your question reminds me of the concept of shooting people on greenscreen vertically to take advantage of the wide aspect ratio. The idea is that once you’ve rotated the image, you can have a full-length shot and then can push in for another angle. The amount you can push in depends on what you’re willing to put up with in terms of image quality. Maybe a medium shot is okay, but a close-up is going to mean going beyond 100% scaling in post—not necessarily a deal breaker for some, but it can be for others.
Image quality aside, you also have to look at it from a creative standpoint. A creative issue with shooting this way is that the person on camera can be constrained with their hand gestures. Since you’re rotating the image, once a hand leaves frame, it will look odd in the final composite.
So, on the one hand, there’s a technical concern, but there’s also a creative concern, and these two concerns are what I thought of when I read your question.
Let’s look at your question from a technical perspective. If you shoot 4K—and, by 4K, I mean 4096×2160 pixels—and then bring in the file and put it onto an HD timeline, you’ll need to scale it down to approximately 47% of its original size in order to see the entire image without cutting off any image area. Unfortunately, since 4K isn’t a 16:9 aspect ratio, you’ll also see that the image doesn’t reach the top and bottom of the HD display. To achieve a full-length shot, you’ll have to scale it to 50%. If you shot UHD (3840×2160), you also would be at 50%.
From a mathematical perspective, it seems like you should be able to blow up the image to 100%, but the math isn’t that simple. Rather than spouting theory and more abstract concepts, I wanted to deal in real-world experience. I spoke with some editors and DPs about this method. The editors talked about image quality—the “technical concern” I mentioned—while the DPs mentioned the “creative concern.” Many DPs would prefer that you never have the option of reframing a shot this way in post, but that topic is for another day.
The editors I talked with told me that with 4K (or 5K), you can’t just go all the way to 100% without some trade-offs. They particularly found this to be the case when cutting between 50% and 100% side by side. While it seemed to be scene-dependent (and editor-dependent), the scaling range was more like 60% to 80%.
While all the editors have their tricks for sharpening the image to “make it work,” it makes you wonder why they have to work so hard. The issue of accurate focus is an obvious one. If operators aren’t critically analyzing focus on set, but instead just aim for “getting it close,” one tiny mistake will be magnified—literally.
Another issue could be the lenses used. The editors didn’t know what was used to shoot their footage beyond RED, Sony, Canon, etc., so they certainly didn’t know about the lenses used. It could be that the lenses just weren’t sharp enough when used on a 4K camera.
And then there’s the issue of oversampling—capturing more resolution than is displayed in the final form. By capturing more resolution and scaling down, you capture more contrast in the finer details of an image than if you captured at the display resolution.
Speaking from the creative perspective, the DPs mentioned that without constantly being able to see framing for both shots—let’s say, wide shot and medium—they might really be missing something. Having a monitor that scales up the 4K is doable, but adds complexity to the rig.
In one instance, a DP tried a straight-on 2-shot and then looked at the single. They found that while the single was “technically” correct based on the scene, from a creative perspective, the composition was wrong. If it had been shot separately, the DP would never have composed it that way.
Obviously, success in using this method depends on the project and the gear. If you know the concerns, you may be able to make use of it. As one director said, “I wouldn’t count on it, but it would be nice to have it in my back pocket.” And his DP sighed….
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