M8 M20 Redo with PixInsight

[willis]

This two DSOs were processed previously with DSS which I've been using for a long time.
viewtopic.php?f=17&t=4186

As many astrophotographers used PixInsight and drawn my attention for sometime. But for a slow learner and slow respondent like me, I needed to wait until the end of academic year! Anyway, I found that PixInsight is something like PhotoShop, which is huge in functions and the learning curve is long. This is my first piece of PI work. I used Registration, Dynamic Background Extraction, Background Neutralization and Color Calibration etc. In handling this image, I found that Background Neutralization is particularly useful! The result is simply great and make the final touch with Photoshop much more easy!

[社長]

Willis 修成正果了

十分十分之好!

可恨沒拍好平場，那些塵埃....

[willis]

有做平場，但隔了一段日子才拍，連塵埃的位置也變了…

[社長]

有做平場，但隔了一段日子才拍，連塵埃的位置也變了…

你拍了 3x25即75分鐘，那對同一個天區多拍一倍，最好是兩倍，然後用averaged sigma clipping疊加，再調一下系數便可除去那些塵埃。