Orion Exposures

I love the Orion Nebula and I'm always looking for an excuse to image it.
So this is my excuse this week.

Starting from the bottom:

1.  Through an eyepiece.  If you look through a telescope you won't see all the colorful currents that myself and others show in our processed images.
Ironically this is the only image here that was processed.  To simulate what we see in a scope I modified a very short exposure and converted it to gray scale.  This gives about the same level of detail I see in my 10" f4.7 Newtonian/Dob.  The Trapezium is clearly visible and the brighter portions of the nebula and star forming region can be seen.

2.  10 second exposure with a camera.  This will give slightly more detail than looking through the eye piece.  The reds(Hydrogen Alpha) and blues (Oxygen 3) start becoming visible.  With them, more of the structure can be seen as well.  The full size and extent of the nebula can still not be determined.

3.  20 second exposure with a camera.  The perimeter of the nebula has grown.  More detail is visible in the previously darker areas, but in the area around the Trapezium it is starting to become blown out.  Each pixel in the camera sensor is like a bucket.  As the shutter of the camera is held open the buckets are slowly filled.  By the time the process is complete there will be some that are over flowing(blown out) while others are hardly touched.  The Orion Nebula is a good example of this.

4.  30 second exposure with a camera.   Again, detail has become visible in what had previously been dark regions.  Areas that had before been barely visible are developing more detail.  The four stars of the Trapezium are still visible, but it's becoming more difficult to distinguish them from each other.  It's not uncommon to stop here with Orion.  30 seconds is a good compromise for this bright of an object.  Yes, this is bright.  The same night these were taken other objects were requiring 3 to 4 minutes.

5.  60 second exposure with a camera.  The Nebula is starting to develop a circular shape.  The Trapezium is blown out.  Once again the detail within the star forming region is developing more and more.  With multiple frames and stacking, noise and atmospheric distortion can be pulled out giving yet more detail.  This was not stacked, stretched or post processed.  I'm stopping here, but Orion does not.  With progressively longer exposures more structures begin to emerge until the entire constellation is one large colorful mosaic.