Del Mar resident Thomas Close has his camera set up nearly every day for spectacular time-lapse artworks. You’ll often find him on the bluffs and beaches of Del Mar at sunset (this photo of Tom with faithful companion ”Sawyer” was taken in Del Mar, not at Torrey Pines).

He also loves the Extension near Red Ridge as a place to catch the pink rays of dawn or a sunset’s fade to indigo. His time-lapse work is especially moving (no pun intended) as it captures the changing colors and marching clouds of our coastal skies.

A retired United Airlines pilot, Tom has a special knack for being at the ready with his digital camera during the tumultuous weather and cloud-sailing skies we’ve been having this winter. Here are three of his Vimeo-posted works specific to Torrey Pines State Natural Reserve. One of them with Del Mar guitar-virtuoso Pepe Romero accompaniment.

We asked Tom to detail his work for you camera buffs out there who love technical challenges. Here’s his description of the process:

“I use a Canon 5D Mark III, and [many of my videos] were shot with a Canon 24-105 mm F4 lens.  An intervalometer is used to capture a frame every two seconds, or 30 frames a minute, and merged into video at 24 frames per second. All images are shot in what is known as RAW format—a proprietary format for absorbing the digital data without compression.

“As it turns out, time lapse (T-L) is most definitely a process. Since my subject matter is nature, especially near sunrise or sundown, we are talking about a very high dynamic range shooting environment—one which changes dramatically from beginning to end, even if the time-frame covers a time frame of as little as 20 minutes. It begins with choosing a subject and vantage point and making a wild guess about the way the clouds are likely to shift during the interval, so that hopefully the action will be in the frame and not out yonder two minutes after you start. Exposure change will be off-the-charts-significant between beginning and end, and assumptions have to be made depending on how the sun will move behind clouds and in clear air, as well as foreground things like Torrey Pine trees affecting all of the exposure changes.

“It is common for me to begin a sequence purposely overexposed by a full f-stop, and end maybe three or more f-stops under-exposed. Sometimes, particularly on longer sequences I might divide the shooting up into three or so sub timeframes, stopping the shooting for a few seconds while readjusting the exposure, then continuing on.

“The individual digital frames are downloaded into an app, developed by a German T-L guru, that interfaces with Adobe Lightroom. The whole sequence is strung out and divided into subsets—for me, usually each 1/10th of the total. Then the frames are processed (developed, for lack of a better term) in Lightroom (funny name, as it is actually a digital darkroom) adjusting exposure, color balance, shadows and such, and also trying to make a smooth transition from the first frame of each subgroup to the same in the next subgroup. The German’s T-L app swallows all the digital metadata and uses mathematical algorithms to transition the individual frames in each subgroup from beginning to end, and each subgroup to the next.

For a sunset, in processing, I typically underexpose the frames ([which were] shot overexposed) at the beginning of the entire T-L, slowly moving to over-exposing those at the end of the entire T-L (which were underexposed at the end of shooting), effectively reversing the process under which the frames were shot. The idea is to get a balanced exposure from beginning to end that approximates what the eye would see, and includes details of the foreground as well as the clouds.  Sometimes it all works, and sometimes you feel like falling on your sword…”