Sunday, April 10, 2011

Oak Creek Spire

I'm a big fan of Startrail photography, and a bigger fan of interesting rock formations. Finding an interesting way to combine the two was my goal for this image. My first foray to Sedona a couple of years ago created, to date, some of my favorite images. They sold well at the Vora Financial gallery, but there were, however, some issues in the process that I needed to iron out. The biggest issue was mainly getting an interval programmable timer.
I spotted this spire from miles away, and wanted to find a way to get up close with the intent of making a star trail composition. Kristi and I hiked about three miles in and cross-countr-ied to a top of a hill. The area is just inside the Coconino National Forest, so fortunately overnight camping would be allowed. We returned with our backpacks, and set up camp on the hill, a few feet from this vantage point. It turned out to be a magical evening from sunset to dawn, the views were spectacular, and the stars vivid. One direction we had views of Cathedral Rock, Courthouse Butte, and Castle Rock. We packed up our backpacks with food, water, wine, and gear and headed out late in the afternoon. The full heat of the day was still present, but we only had a short distance to hike. We set up camp with plenty of light left in the day. It gave us time to pick the perfect spot, and solidify the perfect vantage point to set the tripod. Once the sun started to set, I began taking various images while Kristi made dinner.Although not part of the original plan I was able to grab some interesting images of Cathedral rock, during and right after sunset. I was satisfied at that point to eat dinner and wait for dusk. Before it got too dark I set up my tripod and composed the star trail image of Oak Creek Spire. I took some preliminary high ISO shots (3200), to calculate what shutter speed I might be using. This ended up to be a bit of a trial and error, because the sky kept getting darker. My initial calculations left the shutter open about three and a half minutes, at ISO 100. This was not enough to get the results I needed. The star trails weren't long or bright enough, and the rock face was just a silhouette. It was okay, because my intent was to blend in a well exposed image of the spire. I doubled the shutter speed to seven minutes, which gave me the correct exposure for the rock face. The next hour or so I fussed around with the interval remote timer trying to program it. The directions were a complete folly, as they must have been loosely translated from Chinese, or Japanese, complete with typos (e.g. see for sec., and other serious grammatical errors) rendering them all but useless. I settled on ten five minute exposures for the actual startrails at ISO 100. The rest of the process was all done in Adobe photoshop. Here was my work flow: Import Raw images into Apple Aperture for initial review. Then export the 10 startrail images as 16 bit Tiffs to a predetermined folder, titled "Oak Creek Spire Startrails." The next step was achieved with the help of Dr. Browns scripts for Photoshop called "Stack-a-Matic." This is a free script that basically automates the stacking process. It takes the images and stacks them in layers, then blends them, and ultimately turns them into a smart object where you can flatten them and make a single image. The script can only be started from Adobe bridge, hence the need for the dedicated folder that I exported the Tiffs to. I highlighted all ten images and went to the tools menu, chose "Stack-a-Matic" and ran the script. I used the "maximum" value for the blending, and forced the image to 16 bit mode. After flattening the image I saved it as a new copy to the same folder. I then opened the image of the correctly exposed spire, used the magic wand to trace the rock formation. I created a new layer in the startrail image, and option-dragged the rock formation to the new layer, aligning it over the silhouette. From there I did some final adjustments, and imported it back to Aperture so I can export it to the web. BAM! With the correct tools, and careful planning, what began as a potential vision was realized and executed. Below was the gear used for this image:

Pentax K-5, Vivitar Komine 28mm f2.0 Close Focus Wide Angle: A01 ( for those legacy lens collectors) Programmable interval timer, tripod.

1 comment:

  1. I saw this pic on MacRumors. Thanks for sharing! I'm just getting into photography and the art that you guys create with your lenses and photoshop amaze me.