Optically, it is done by changing the focal length of the lens during the exposure.
As shown, you can do it in post as well.
Yep thats it...sam & i were trying that method at yosemite. Cant be done well without a tripod. Just set the camera for a longish exposure (maybe a second or 2) & have it at full focal length & hit the button...as it has its shutter open just roll the lens to the other end of its focal lenght. Dont think it matters whether you go from max to min or the other way around.
Comments
1. Copy the backgroun layer. Optionally select an area not to be blurred. I used the lasso to loosely select an area. Feathered 30 pixels.
2. Invert the selection Ctrl-Shft-I
3. Filter->Blur->Radial Blur. Blur method:Zoom Draft Quality, Amount: 22
This is what I got:
You need to experiment with the amount and the quality, but it should give you something like you saw.
The other possibility is maybe it was a Lens Babie. Hard to tell from the little photo.
Brad
www.digismile.ca
If you have a camera with mechanical zoom, you can also do something similar by zooming in, or out while depressing the shutter release.
Steve
As shown, you can do it in post as well.
"Failure is feedback. And feedback is the breakfast of champions." - fortune cookie
Gus
A former sports shooter
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