Thursday, June 14, 2012

As Time Goes By. A Quick Look Into Time Lapse Photography

Time lapse , simply put, is a series of photos taken at a given interval over a period of time. The photos are played back in a video at a high rate to give the impression of a video. Typically these are things that happen slowly over a long period of time. Think of clouds moving across the sky, a flower opening or the stars/moon moving in the night sky. Yes, it can be time consuming both when taking the photos as well as processing, but the results can be pretty cool. Here's a quick example....................

Equipment you'll need........

  • A sturdy tripod
    Even the slightest movement will show up in the final product, so use a tripod that will hold the camera still and in the same position for an extended period of time. HINT.....wind is your enemy.

  • A remote shutter release.
     Pressing the shutter manually can cause the camera to move ever so slightly. Most cameras these days have a timer function, but usually can't be set for more than 10 seconds. That function also uses battery capacity. Save your batteries for the shots and get a remote switch. Some cameras are picky about which ones they work with as well as how you connect the two together, so take a few minutes and make sure it will work with yours. You can get these gizmos in any camera shop, through your camera's manufacturer or online (EBay, Adorama, Amazon) If you are shooting for more than a few minutes, I would highly recommend a  Intervalometer.  This is a handy little tool that lets you set it....and forget it. I'm speaking of the interval between shutter releases. Some also have added features like exposure time when the shutter is open. Google the term and you will find tons of different kinds in all price ranges. Unless you plan on standing with your camera for hours either counting to yourself or looking at your watch, these things are indispensable. HINT....set the interval between shots long enough so that each image has time to write to your card without going to your buffer.

  • A memory card with lots of space.

     We are talking about taking a lot of shots here. One shot every 5 seconds for 8 do the math. Nothing worse than your card filling up right at the critical moment. Don't think you can just stick another card in. You WILL move the camera and you WILL mess up your lapse.

  • A fully charged battery or an AC power connection.  
    Again...lots of exposures...lots of time. don't let your camera die due to low batteries.

Now the technical stuff.........(Camera Settings)

DO NOT shoot in program mode!!! If you do, the camera will adjust for each individual shot and your final product will be all over the place. The first setting to make is White Balance. Do NOT use Auto White Balance. Set it using a grey card or simply choose one of the presets your camera has built in. I use a White Balance of 5200K...but that's just me. These other settings are as much art as they are science. Remember you will be shooting over a long period of time and lighting conditions will change, so plan for that from the start. Choose a reasonable ISO setting. If you are shooting stars at night, the sky is the limit (no pun intended) as for how high you can go with this setting, but be aware that, generally speaking, the higher the ISO, the higher the amount of digital noise in the shot. Shutter Speed should be set to give a good exposure given the conditions and your ISO setting. I can't believe I am going to say this, but.....don't set your speed too high and don't worry about getting a tack sharp shot. I say this for two reasons. When you put all these images together, you may see a phenomena known as "flicker". While there are several reasons for "flicker", the most common is too high a shutter speed. The other reason is so you have a SLIGHT amount of motion blur in each shot which helps give a smooth transition from frame to frame. So drag your shutter just a bit either by the speed setting or by use of ND Filters. Set your f Stop for the desired effect and exposure you want, but I would start with something around f /11. If all of this seems a bit daunting, take several test shots at various settings and see what works best for you. Another way would be to run off a few shots in program mode and make note of the settings the camera automatically applied. Switch to manual and use those settings. Finally, take your camera and lens out of auto focus mode and set it manually. That way your focal point stays the same throughout the series.

After firing off all these shots, you'll need to process the images and a program to assemble them into a "video". Use the program you normally do to adjust and process your images. No need to adjust each individual shot. Simply select the first image, adjust it to your liking and then copy and paste the corrections to the other images. Since your camera setting didn't change (you WERE shooting in manual mode) the changes in the conditions over time will come through. There are hundreds of programs out there that will create time lapse videos and range in price from free to hundreds of dollars. If you are doing this for fun and the experience....go free first. For short clips, Picasa has a nice time lapse feature and it is free!

So set up, sit back and have fun!