Moon Photo Stacking

A few weeks ago I was out looking for birds to photograph with my Nikon P950. I saw the crescent moon overhead and took a few handheld shots of it. I thought I might play with some astrophotogray stacking software, so I took a few seconds of 1080p video too.

After doing a little research, it seems that the consensus software to use, for planetary and lunar shots, is AutoStakkert! 3 and RegiStax 6. These are both older Windows donationware apps, and I was happy to find that they both ran fine on Ubuntu with wine.

The concept of stacking images is fascinating to me. I've played with stacking images before where you simply take the median value of each pixel across the stacked frames. This removes noise and helps improve detail. But these astrophotography tools appear to be using much more sophisticated algorithms. It's awesome that these tools are freely available, and from what I've seen amateurs are able to use them to make very high-quality images.

After watching some excellent videos on YouTube (this one for AutoStakkert!, and this one for RegiStax) I took a stab at it and am surprised with my results.

This is a grid of before and after images (click to enlarge). Even when greatly shrunk down to fit in this image, you can see more detail in the "after" images on the right. Some of that I assume is just due to the wavelet sharpening, which may have a similar effect on a single, unstacked image.

Here is a closer look at the 1080p video shots. I stacked the best 44% of the video frames I took, which I think amounts to 100 frames or so.

And below is the same smaller section of the stacked and processed full-resolution (16MP) still shot burst I took. I stacked only the best 3 of 8 total frames. You can see a good amount of detail was brought out when stacking just three frames — but I really should have taken a few more bursts so that I could at least stack several dozen images.

Finally, here is the full-size processed image made by stacking 3 16-megapixel frames (click to open in new tab). As you can see from how purple it looks I must have messed up some color balance setting somewhere along the way.

Perhaps someday I'll try some night shots with a tripod.