Linear Fit Clipping ! ! !

[pscammp]

Hello all,

Just wondering if I may ask a question ref Linear Fit Clipping ?

I used Linear Fit clipping in the Image Integration module due to the amount of sub's I had after reading
documentation etc.

When the final Integration is done after all the calibration routines I end up with my master Light, a Low
rejection image, High rejection image and a Slope Map.

What on earth is a slope Map, what does it show, and how do you interpret what is shown in it, and, how
can you tell you have a Good Slope Map or a Bad one  ?

Attached is a jpg image of my Slope Map just for visual reference.

The image is of the IC63 area. The green blob just left of center is a reflection in the image caused by the
very bright star to the right. The Grim Reaper himself would appear immediately to the right of the green
blob.

Thanks for any (Pix)insight

Paul

[avastro]

Hi Paul,
Look at this link http://www.pixinsight.com/doc/tools/ImageIntegration/ImageIntegration.
In Rejection Maps chapter, down in the page,you'll find some explanation.
" the linear fit clipping algorithm generates slope maps, whose values are proportional to the slopes of the fitted lines for the integrated pixel stacks. In a slope map image, each pixel indicates the slope angle in the range from black=0° to white=90°. A slope map informs you about the magnitude and spatial distribution of brightness variations in your data set."
Hope that'll help.
Antoine

[pscammp]

avastro,

Thanks for that, had a read and it makes more sense now

Paul