I first found out about time collapse photography when I was looking around the internet for a way to condense a time lapse sequence into a single frame. My search queries were all over the place: "time lapse one photo," "many pictures into one picture." My librarian mother would be disappointed in my research abilities. Eventually, I found this article from Matt Molloy who gives a really good summary of how easy it is to create what he calls "timestacks." Inspired by his amazing images, I set out to create my own. I was quite pleased with how straightforward this process was, and how cool it looks outside of the standard "star trail" subject (in this case, clouds).
I shot a time lapse sequence in my backyard with my Sony a7Sii using the in-camera intervalometer available for sale on the camera's app store (we're at a point where cameras have app stores, I guess). I'm really disappointed with Sony's intervalometer app- it's cumbersome, confusing, and unintuitive even beyond their already-clunky menu systems on the rest of the camera. After accidentally creating a low-res .avi file instead of a discrete sequence of raw photos, causing me to miss some really perfect clouds, (and corrupting my phone's microSD card, by the way) I decided to just buy a standalone intervalometer to avoid future headaches. Anyway, this sequence was then imported into Adobe Bridge CC for editing and image processing. Once I was happy with basic contrast and exposure adjustments, I applied the same develop settings to each image in the sequence, then exported them all as .jpg for smoother stacking in Photoshop. After importing the files into Photoshop with the 'stack images' script, I was then able to set the blending mode for each layer to Lighten and play around with my settings and adjustments until I liked how it looked. I ended up only using about seven of the original 500 photos I captured; it just took some poking and prodding until I found a good stretch of images. I would have liked to have used a shorter interval between shots (I think I was capturing an image every ten seconds in this case) for a smoother painting effect in the clouds, but as a first effort, I'm excited by the outcome.
This process probably didn't take much longer than ten minutes when it was all said and done (excluding the initial time lapse photography, of course) and I'm thrilled with the results. I've been pining for the right weather since learning of this effect and I'm really looking forward to experimenting with settings and subjects for the perfect "vertical time lapse," as I've taken to thinking of it.
Here's a step-by-step video tutorial of how to assemble a time lapse sequence into a timestack: