how do you reduce size of stars, or their impact in an image?

[h0ughy]

I have just taken an image of M31 over 5 nights at Queensland Astrofest.  Now processing the image I find that I have 7h and 57min worth of useable data that I have stacked and processed to date the image below.  How do I reduce the star size and their impact in the image to reveal the galaxy better?

It is a stack of images taken with a cooled canon40D at iso1600 at f4 taken through a 300mm FD canon lens.

[Harry page]

Hi

have a look here mate  http://www.harrysastroshed.com/mask.html



Harry

[h0ughy]

Hi

have a look here mate  http://www.harrysastroshed.com/mask.html



Harry

thanks Harry -  you come through again and again

[cfranks]

Harry,

I followed your tutorial to try to reduce my stars.  Dragged the Lum tag on to my image and the whole image turns red!  Is it a difference between your tutorial (PI 1.5) and my PI 1.6 or is it me.

Charles

[Nocturnal]

Better find the video about masks and watch that first. The red is harmless (but indeed alarming). It merely indicates what is protected and what is not.

[Harry page]

Hi Charles


Sorry in this case its you 

As sander said it just means the mask is in place and the red is the protected areas

I tend to use the show mask icon on the top bar which will hide it from view but leaving it active


Harry

[cfranks]

Thanks Harry/Sander.

Charles