Barry, here's one for you.Spent a quick overnight Sunday-Monday down in Capitol Reef National Park to do a bit of night shooting during the young moon. The nearest town of Torrey has worked specifically to reduce their light pollution into the park, and it makes a large difference. In fact, the International Dark-Sky Association awarded the park Gold-tier International Dark Sky Park status a couple years back. IDSA Gold level "corresponds to pristine or near-pristine night skies that
average close to natural conditions."
I went down to try out some purposeful image stacking to reduce noise and bring out some of the fainter detail in the galactic core. I'd done a little before, but only with about 3-5 frames. This time, I wanted to try with something a bit more robust, so shot 50 individual exposures. I don't yet own a star tracker, so I had to keep my shots short - 10 seconds n this case. Used my Sigma 24 mm f/1.4 lens, stopped down to f/3.5 to minimize it's inherent sagittal astigmatism in the corners when shooting star fields wide open. I also cranked the iso up to 12,800. I knew the raw files would be very noisy at that high a sensitivity, but that's where the stack comes in.
Got everything off the camera's card, then set to aligning, and median stacking in PS. The noise, low contrast, and general lack of detail melted away. In short, I was able to manage what is probably the most detailed image of the core I've ever managed to capture. Strongly recommend this technique for any photography of stationary objects, requiring maximum detail and definition.
(Sadly, this is about a 1/5th sized reduction, for space, and all that here...but you get the idea.)
Reply With Quote
Bookmarks