Heres something that might help you, I didn't narrate the steps , I tought they were pretty ovious,
1.- Duplicate Image, Close original image
2.- lighten image: Image>Apply Image in the dialog box change the blending mode to
Screen and the opacity to 100%, this will create an overexposed image.
3.- Duplicate overexpossed image.
4.- Blur the copy overexposed: Filter>Blur>Gaussian Blur play with the radius usually it
will be between 20 and 50. when done set the blending mode to multiply.
5.- Flatten image
HAVE FUN WITH IT!!
