La esquina del cibernauta: An Introduction to Time-Lapse Photography

Es maravillosa la posibilidad de expresiòn que se logra con la fotografìa time-lapse.
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An Introduction to Time-Lapse Photography

vía Digital Photography School de Chas Elliott el 27/04/09

We have talked about time-lapse photography a couple times here on DPS. First here, and then last year we featured a photographer named Ross Ching who showcased some of his amazing time-lapse photography work. This unique use of DSLR cameras was something I've wanted to try, but until now, I hadn't got around to playing with this feature. When I stumbled upon a completely new and updated version of his original project Eclectic 2.0, I decided it was time to end the procrastination and give this a shot (or many many shots).

I'll talk more on the latest project that Ross has been working on below (video of it is below) as well as some other amazing works that can be found around the web, but first, let's give those new to the concept a brief background on time-lapse photography.

Eclectic 3.0: The Roads Less Traveled from Ross Ching on Vimeo.

The beginnings

When did the technique originate? Many of you may have heard of Eadweard Muybridge or seen his work of a horse captured frame by frame in motion. His work preceded the celluloid film-strip we use today. Rumor has it that in order to settle a wager of whether a running horse is briefly mid-air with all four hooves losing contact with the ground, Muybridge setup a complicated rigging of 24 cameras. He used trip wires to trigger the shutters of the cameras as it strode by. Once strung together, of course, a "moving picture" was created which revealed that all the hooves do, in fact, actually leave the ground.

Today, film is typically captured at 24 or, in some HD applications, even 60 frames per second. By stringing the images together rapidly of course, you get the feeling of seamless motion. When we talk about time lapse, in contrast to what Muybridge was attempting, slowing down a real event, we are more interested in speeding up an event. Although you still string multiple images together, as in the Muybridge experiment, the difference is that you program the camera to pause slightly between each photo. You then run these frames together at a common speed, i.e. 24 frames per second. By doing this, you create the illusion of watching an event occur many times faster than it did. The first recorded use of this technique was done by the cinemagician Georges Méliès in a feature film called Carrefour De L'Opera in 1897. Of course many others soon followed.

Set your settings

To save you from hours of sitting and pushing the shutter release, many of today's DSLRs come with interval features built right in. If your camera is missing this feature, external shutter release cables with built-in timers are also available. Better yet, you can build your own "intervalometer" for about $20.

On to the shooting… First thing you should consider is what camera settings are best for time-lapsing. It is extremely important that every image setting be exactly identical to the previous in order to avoid a seizure inducing flicker or strobe effect. No matter how smart your camera is, each frame my come out with a slightly different setting than the last. Solution? Ditch every auto setting your camera has, from auto ISO, to auto white balance, to auto exposure.

If you're not used to the daunting M mode, don't fret. Simply use your camera as a basic light meter. Switch to aperture priority, choose your desired aperture (for landscapes use a smaller aperture, such as f16 to provide a greater depth of field), then make a mental note of what the camera assigned as the corresponding shutter speed. Flip back to manual M mode and duplicate the settings. If you are hoping to capture the blurred movement of cars, streams or any type of motion, you might start with shutter priority and then go back to M mode. Interestingly, having images with a slight motion blur can actually increase the smoothness of your final film. If you were to view a single frame of an action film, you may be surprised to see it isn't as crisp as a still frame from a high speed DSLR would be. For a brief explanation of why blurring simulates fluidity, sharpness simulates a stuttering effect look here.

If you are shooting a sunset or sunrise, remember to weight your exposure on the bright or dark side so that as the environment changes, your final images are still acceptable. Lastly, if you are shooting a camera with a high megapixel count, you might be better off using a lower quality jpeg setting. The highest quality setting probably exceeds any HD format and the smaller images will help ease the load on your computer when arranging your images as a sequence.

Time is on your side

Next up is deciding how many frames to take each second. A little bit of math is involved here. The guys over at Time Science explain it this way: "Consider a movie in the cinema which is normally recorded at 24 frames per second. You could create a time-lapse by recording one frame every second. When you play the movie, the frames recorded over a period of 24 seconds are played back in one second. So the recorded scene moves 24 times as fast as the real scene. One hour of recording would play back in (60/24 = ) 2.5 minutes." The math can get tricky depending on what you're trying to capture, so they've built a simple time-lapse calculator on their site here to help us out. Simply put, you may have to shoot a few hours for just a few minutes of footage, so bring a book and pack a lunch.

First time for time-lapse

Heading down to D.C., I decided to try my hand with this technique. For my first attempt, I decided to go 1 image for every 4 seconds. I found some slow moving paddle boaters that would be good test subjects. Unfortunately I didn't lug my tripod along so I found a nearby wall to set the camera on. I tried a few different angles before turning the camera around to capture some of the passerby's.

As mentioned above, a slower shutter speed will smooth out the final results, but I wanted to keep my shutter speed fast so as to create a chaotic feel that I find appealing. After seeing the final result, and thinking it needed a little spice, I decided to try running each image through a filter before arranging them into a sequence. I recently reviewed PhotoTools 2 and I knew that it had a built in batch tool. I chose a vintage "Holga" filter, pointed it to the entire folder of images and let it go to work. About thirty minutes later each image had a black frame and blurry smear added. If you decide to apply a filter on your images, you don't need Phototools, of course, since there are batch features built into Photoshop as well.

Now the good stuff

Ok, I know you wanted to see how things should really be done and there are some amazing example around the web. First up is Ross Ching's new creation "Eclectic 3.0: The Road Less Traveled". Not only did he create a stunning film, he used some unique twists in the process. Some of his secrets are in his how-to video here. I found his technique of extremely slow panning especially interesting, as well as his use of a tilt-shift lens to give the illusion that you are viewing miniatures. If you aren't familiar with tilt-shifting, a future DPS article is in the works.

Next up is another very cool tilt-shift time-lapse featuring the Westpac Rescue Helicopter Service, done by Sydney-based photographer Keith Loutit. Make sure to view this in full screen HD and it will blow your mind.

Next are some very cool videos by 599 Productions. They have some interesting shots of late night city scenes and highways.

Lastly we have a humorous video done with a slightly different stop motion technique, but it's funny enough to include here.

Hope you enjoyed this short journey into the possibilities of time-lapse photography. Share your own finds or better yet, your own attempts at time-lapse photography.

Post from: Digital Photography School - Photography Tips.

An Introduction to Time-Lapse Photography