12ca2c1e_hotography_Tips_and_Techniques__2
[0] DSOs [1] Moderate to Very difficult – but can been done. Must have tracking and a camera that can do long exposures (15 to 60 secs depending on aperture). Light pollution factors in especially in fainter DSOs. [3] Very Good to poor – With a great amount of effort and practice, mostly on the processing side. Larger apertures have much better results. [2] 
Difficult – Almost always necessary to combine multiple shots. Hot pixels / noise must be subtracted. Balance of contrast and color is critical.
Digital Camera Astrophotography Tips and Techniques
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