Quote:
Originally Posted by Lognic04
Alex, all stacking does in a deep sky sense is reduce noise, a common misconception is that it makes the image brighter/more details, but in the end a 60 second shot if always a 60 second shot, even after stacking. It is really hard in my opinion to bring any faint detail out with 60 second subs, maybe impossible.
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Not impossible but certainly not for novices. You really need to start thinking in terms of signal to noise ratio with astrophotography.
Signal is the information in the field of view you want to keep.
Noise is introduced information by the capture system that you dont want. Its very weak and not often seen but its always there.
For everyday photography the same applies but in that case the Signal just overwhelms the Noise that you rarely ever notice it.
In astrophotography the signal is often as weak as the noise so you have to amplify it a LOT to see it, but that also amplifies the noise too. Noise reduction only does what it says, it REDUCES noise, does not remove it. By stacking the noise gets averaged down deeper but its still there. What it gives you is more room to amplify the signal up to see it without noise becoming too dominant.
It this that gives people the misconception stacking makes brighter images, it absolutely does not unless you used the wrong stacking method. Its not the point of it, it just gives you more room to adjust your image before noise ruins it.