M32 & M42, up to two hours stacked

So here is the same shot as in the previous post, with another hour added to the stack. Since it needs to be stretched less to achieve similar brightness, there is less "stress" visible in the image; the background is beginning to become an even black, etc. I expect this to take a total of 5 hours in the final stack to really work well, but I want to post the individual steps along the way. It takes 3-4 hours of shooting get 1 hour's worth of usable subs.

While most photographers would try and get a ten minute exposure to bring out the lower half of the nebula (which is FAR fainter than the upper half, I have found that my method of dealing with light pollution (which essentially limits my exposures to 30 seconds) is turning out to be a way to show bright nebula with the dynamic range adjusted. A normal photograph that brought out this much of the lower "jaw" of the fish's mouth would have the area at the top around the Trapezium totally blown out. One I complete this photo after another 3 nights of shooting, I should be able to not only capture the fainter regions, but still show detail in the very bright regions, and probably still resolve the Trapezium in the center of the brightest areas. The downside is that it does take many nights, and many hundreds of individual photographs, aligned of several nights of work. I've started calling the process "speckle stacking", since it really is a weird variation on the "speckle imaging" used by modern giant telescopes, but with exposure in the seconds, not milliseconds. It's a very low-tech way to take advantage of the pro's high-tech method.

I have an idea what may be causing the banding on the left and right images-I'll know after my next photo shoot if I am right.

And finally, full circle

When I decided to get serious about learning to shoot astro, if was February of this year, and Orion was still reachable in the early evening. So here is a good comparison between then and now-this shot is 55 minutes exposure, no multi-night shooting, just using what I have learned over the year. M42 is the perfect nebula to start learning with, but the level of detail in there just keeps going forever; there is no risk of getting bored with it.

I still have all the problems I started with, just in lesser degrees...vignetting is still a serious problem, and even the use of a good light box won't eliminate it. I'm still only able to use roughly half the subs I shoot, and I'm still spending more time tinkering than shooting. This shot from tonight is just going to be a foundation for more exposures; that will take care of the darkened corners and the trademark Canon DSLR banding visible up the left side, while each night's shots will bring out more and more detail inside the "fish's mouth".

It's still been a good year for learning-here's a reminder of what I was getting 10 months ago of the same target.

Running Man Nebula

This nebula lies just above the Great Orion Nebula, which means that I'm actually getting around to regions I was trying to shoot when I started this thing 10 months ago. When you look at Orion's sword, the Great Nebula is the middle clump of stars, while this is the top clump. It's been given three catalog numbers, since there are actually three separate areas of glowing gas that just overlap from our point of view. So say hello to NGc 1973, NGC 1975, and NGC 1977. Most people just refer to it as the Running Man.

Please forgive the satellites...that's the price we pay for cable TV and global telephone service-the geosynchronous orbits of most comm satellites carries them right smack through Orion's belt. Actually, each satellite seen in this area is stationary over our heads; the appearance of motion is caused by the telescope moving to track the stuff in the background. The software used to stack photos usually discards satellite tracks as noise, unless they are very bright, which is what happened here. Only 5 minutes exposure, so I couldn't toss the subs with streaks in them.