4 ways to get Variable Blurs in GIMP

[torstan]

It can also be done with quick masks - very similar to the feathered lasoo method.

Start with the standard circle and run a light blur over it so you have something like this to start with:



Now click the quick mask button (circled in green on the following image). It should now look like this:



Now use the gradient tool to get a nice graded selection. Drawing over the image with white creates a see-through areas of the mask (the red) that will be interprested as the selection later on. Therefore using a gradien tool we can leave some areas black (unselected) and then as it fades to white, the area becomes selected. Using the gradient like this:



... should give a quick mask that looks like this:



Now click the quickmask button again to turn the quickmask into a selection. You should now have what looks like a rectangular selection around the bottom. With this selection in place, run the Gaussian Blur filter again at 100px to get the following: