Wizard needs a few tricks


First light with the Wizard nebula. RC10 with 0.67 reducer. HaS2O3 + RGB
I’m happy with the colors but I’m still not entirely satisfied with the star color. I found it too difficult to remove them before stretching the NB files. I tried blending in RGB star color afterwards but it is not entirely working. So I need a few tricks…?


I use the method that RickS suggests on the PI forum:

It works for me without too much trouble - once I got over the initial hurdle of understanding exactly what he was doing.

There are other suggestions on that same forum post: https://pixinsight.com/forum/index.php?topic=9493.msg60616#msg60616



thanks Kinch - I think I do the equivalent - I LRGB combine both the NB and RGB stars with the same master luminance and then use PixelMath and a starmask to combine (so the luminance information is the same). The issue is that while the star color is ok, the margins of the stars take on the wrong color as the color information in the NB and RGB files does not transition at the same point. I few more cloudy nights might crack it.


Hi Buzz, yes, stick with it. For me Rick’s way has proved to be worth the effort of learning. With that method, the LUM plays no part…you only move the star colour over via the “a” and “b” channels.



Thanks, I think there may be a subtle difference. I get the feeling that LRGB combine still uses some luminance data from the RGB file. I will try your method and see how it goes.


Tried again - I reduced star sizes on the NB files before combining and then used a simple mask and star substitution after using the same Lum on LRGBCombine on both NB color image and star image.
I fiddled with the color balance too while I was at it.