Pixinsight DBE with just five markers.

[ollypenrice]

I found this interesting. A guest sent me some linear Iris RGB data to play with. I always start with DBE and had my usual shock when the image, taken in LP, was bright orange! I'm not used to that. After an initial panic I found one point in each corner and one near the middle which were genuine background sky, not part of the copious dust clouds almost filling the image. I hit the Apply button and out came a perfectly flattened and colour balanced Iris. The underlying data was first class.

So the moral is, You don't need lots of background markers. Exactly as Harry says on his tutorials. 

Olly

[wxsatuser]

I have done it before with quite a lot but now just let it pick a few, results still look ok to me.

[r3i]

I always start with DBE and had my usual shock when the image, taken in LP, was bright orange! I'm not used to that.

Welcome to our world Orange images are quite the norm for the moisture laden, light polluted UK skies.

[harry page]

Hi

Try it with 3

Harry

[NickK]

The sky is normally quite flat gradient. 3 gives you a 2D plane to work by thus giving you a gradient. For wide field (300mm) pictures then this approach is less accurate as you start seeing the shape of the light pollution of a city in the distance for example. In that case you want to model that shape - so one in the centre and a series of circle of points around it is your best way of approaching that.

[NickK]

Welcome to our world Orange images are quite the norm for the moisture laden, light polluted UK skies.

Not quite as Starwars led you to believe.. Dark isn't bad lol.

[Dave_D]

You mean the sky isn't naturally orange?