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Hi I am trying to simply make a point light on a black background.   But when I make my light it always exceeds the size of the canvas.   How can I make sure part of my light doesn't get cut off screen? 

Thank You
Are you using a filter? if so which one?
A brush? which one?
A script? ....

Please explain your process of when I make my light, a screenshot to your explanations would be a big plus
I think you mean something like this. A quick example : make a path on a layer, press 'enter' (a selection from the path is made) and fill the path wit the color you like (in this example white). Then 'Select / None' and blur the result (Filters / Blur / Gaussian Blur). Draw an ellips on the bottom of the beam, fill it with the same color you used for the beam and blur the result. I used the 'gradient tool' on a separate layer and set the layer mode on 'colour erase' to blend the light beam a little.
 [attachment=6448]
 [attachment=6449]
I think you'll find the original poster is asking about Filters>>Light and Shadow...>>Lighting Effects...

[attachment=6450]
(07-28-2021, 10:25 PM)Rtferg88 Wrote: [ -> ]Hi I am trying to simply make a point light on a black background.   But when I make my light it always exceeds the size of the canvas.   How can I make sure part of my light doesn't get cut off screen? 

Yes there is a difference - a point light is not the same as a spot light although can be interchangeable.

Is it all black background or is there something that you are illuminating ?

All black background then a circular fuzzy brush of suitable fuzzyness Wink  

The problem with the lighting effect plugin (apart from being ancient) is it works from the center of the image to the edge of the canvas. You can sometimes get round this by temporarily increasing the size of the canvas (well oversize) Image -> Canvas Size

Then apply the lighting effects and when satisfactory return the canvas to original size. Image -> Crop to content

A couple of screenshots: https://i.imgur.com/mrIDhC7.jpg

If you give more details then probably some alternatives offered.
(07-28-2021, 10:25 PM)Rtferg88 Wrote: [ -> ]Hi I am trying to simply make a point light on a black background.   But when I make my light it always exceeds the size of the canvas.   How can I make sure part of my light doesn't get cut off screen? 

Thank You

One option would be for you to use a G'MIC filter:

If your version is the same (Version 2.9.2) as mine or older, you could try with the filter: G'MIC - Lights & Shadows - Light Rays

But if you have version 2.9.7 or later you can try: G'MIC - Lights & Shadows - Guided Light Rays

(07-29-2021, 11:46 AM)rich2005 Wrote: [ -> ]The problem with the lighting effect plugin (apart from being ancient) is it works from the center of the image to the edge of the canvas. You can sometimes get round this by temporarily increasing the size of the canvas (well oversize)  Image -> Canvas Size

Then apply the lighting effects and when satisfactory return the canvas to original size. Image -> Crop to content

A couple of screenshots: https://i.imgur.com/mrIDhC7.jpg

Rich2005, nice tip! Thx!
I came up with a possible g'mic filter as well. Relief Light Initially seems unlikely, you need to mess with the sliders.
https://i.imgur.com/J2ZJpcJ.jpg
(07-29-2021, 05:26 PM)rich2005 Wrote: [ -> ]I came up with a possible g'mic filter as well. Relief Light  Initially seems unlikely, you need to mess with the sliders.
https://i.imgur.com/J2ZJpcJ.jpg

What I got using G'MIC - Lights & Shadows - Light Rays.
https://i.imgur.com/Rq47qtR.png


It would be easier to try to produce some result if it was clear what the user of post #1 is trying to achieve - an example image would make it easier.
I am trying to make a stadium backround.  I wanted to make a point light that I could copy/paste.  

But yeah the point light is always bigger than my canvas so if I were to try and cut it from the canvas the bottom part of the point light is cut off.  And I lose the bottom of my point light.
Which of this lights would you really simulate in gimp ?
[attachment=6460]