[gb]

I've been doing some reading on this as my EM-1 is said to be too noisy at high ISO's and long exposures. I want to try this technique. My goal is to shoot the Milky Way with landscape scenery incorporated into the photo. So, the stars are moving, the landscape not. The question is if I have say 20-25 seconds max before I get blurring and would, in a single exposure shoot, F2.8 W/24mm lens ISO 3200-6400 and wanted to shoot instead 4 or 5-5 second exposures would I simply shoot 5 exposures (say) at 1/5th the amount of light each and then combine them with addition or is my math wrong here given the doubling of exposures with each F-stop? If this is right I could hold my ISO to 3200 or 6400, perhaps 1600 with in camera Noise Reduction off (I'll probably try all three) and just shoot the 5-4 to 5 second exposures (I'll try both). I'll shoot one dark frame image before and one dark frame image after and add them to the stack. It sounds like a couple of good options for combining the images are Photoshop (Lightroom maybe) with manual alignment or perhaps Keith's Image Stacker or Nebulosity with later touch up in PS or Lightroom. I'll compare the results to shooting a single image with Noise Reduction turned on. Is this reasonable? Suggestions.

[Cyclopath]

I spent a night at Slate Peak, and a guy showed up with a tracker and some high tech gear. He was talking about stacking images, about coming out to shoot galaxies over multiple nights, and some really advanced techniques. Obviously a tracker isn't going to work if you want part of the earthly landscape in your frame. But the concept is sound. I haven't done this myself but a lot of people do. From the little bit of reading up I've done on it, it sounds like you probably want software to align and combine the images instead of having to do it yourself, but I can't say for sure. When you experiment with this, please show off your results!

[mike]

v2 used to be free Astrostack haven't tried it myself. If you want to try v2 send me a pm

[Jim Dockery]

gb, I assume you watched the tutorial video on the Lonely Speck site about this - it is a fairly involved process using Photoshop's auto align function and masking off the foreground landscape so that it isn't involved in the star alignment, then merging the resulting sky back with the foreground. I tried it with poor results, but will be shooting to do this on my trip to the SW starting next week. Will post results and hope you do too. Good luck.

[gb]

I'll watch that tutorial after the weekend - rainy next week. I found these tutorials also. It will be a steep learning curve for me as I've not used Photoshop for ten years and have never used Lightroom. Original tutorial:

And this one which is very detailed and can be downloaded as a PDF (handy for side by side while learning): http://www.askc.org/Astro_Photo%20Workshop.html