Took advantage of co-operative weather this weekend to have a first go at a star trail panorama, at Bear Lake in Rocky Mountain National Park. I’ve visited this place many times: it’s beautiful, dark, and close to a huge parking lot that so I could retreat from the cold and wind while the cameras were firing away. The setup went as planned, though with two DSLRs mounted to the rail tripod stability was not great. I packed snow around the legs to try and cut down on vibration. For star trails dark frame subtraction is a no-no, so I set the exposure at what was intended to be a balance between depth and noise – 30s, f/3.5, ISO 1600. Once it got dark enough (for future reference that’s about an hour after sunset) I locked down remote releases and retired to the car for dinner! (Not without some irrational unease at abandoning all this gear in the backcountry.)
I ran for two and a half hours, with the Moon in the sky to illuminate the peaks for the last half hour. The result was a set of 280 images from each camera, which were processed in Lightroom and stacked with StarStaX as usual. The nearly full Moon proved to be pretty bright, so I used only about two hours of exposure. Here are the individual stacks.
Pointing ultra-wide lenses up toward the sky gives a lot more distortion that I’d realized, and despite the generous overlap Autopano Pro balked at stitching this automatically. The problem was mostly noise and a lack of clear features in the foreground, and the stitch improved dramatically after I added back the EXIF data (removed by StarStaX), lightened the foreground, and applied noise reduction before stacking. Even then the stars were a mess, but that’s easily fixed by adding manual control points to the sky.
I reckon more sky and less foreground would have been better, and even thought as much while setting up. But I wimped out seeing the unexpected distortion and fearing that my tripod might topple in the wind if pointed any further skyward. Happy with the result for a first effort though!