If you get successful result on your gg and fresnel, try to use the same focal length as the one you have. To check for focal length, hold it out to the sun and put some paper underneath. Try to move it up and down until you get 1 small point (the sun) and measure the distance between the gg and paper. Hope this help, thanks.

Quyen

I just had an interesting observation - in VEGAS (which I use to edit my footage), on the timeline I can see the gradient of the hotspot clearly in my footage - because of the way the timeline is setup, the image is sized on the timeline, and I can see the concentric circles of the hotspot colour all the way from the center point to the outer point. This is going to be a good indicator for me on how well I get rid of the hotspot!