You could enlarge the foreground object slightly to "trap" your cut, or alternatively shrink the background 1 percent or so. With the blur applied to the background, I don’t think anyone would be able to distinquish the size difference.
Interesting suggestion…. I can see how that might work for small amounts of gaussian blur, although with large degrees of blur, I would imagine that it might be hard to "trap" enough in this fashion.
Thanks — it’s always great to hear other people’s approach, as you never know how someone thinks to use the same tool!
Cal.
One method I use that is surprisingly simple, you simply duplicate the layer in the layers palette, that is, drag the layer to the create layer icon on the bottom of the layers palette, gaussian blur the dupe layer, create a mask on the dupe layer, INVERT THE MASK, Ctrl-I or Command-I with mac,then with WHITE as your foreground color just paint in the blur where you want it. Of course this would be a different scenario if you are placing the subject of layer one into an entirely different background, then of course you would have to remove the subject from its background, obviously then, the background you place the subject into could be blurred indipendantly of the subject. Let me know if this is helpful
Alternatively, you could use the rubber stamp on the background layer to copy whatever appears in the background "outside" your cutline to also appear on the "inside" of your cutline, so that when it is blurred, the stuff that bleeds back out is the same color/pattern as the stuff that should be there in the first place.
A little more hand work, and alters your image further, but might produce a good effect.
Clay
I’m not sure that will work, rwwilson, you would still get the "spillover" that Cal is referring to.
I’m not sure this will work either, but I don’t have time to try it.
Make sure you have this (or similar) layer stack:
– Foreground
– Background
– Photoshop Background Layer (original composite image)
Delete the shape of the foreground object from the background, and lock the background’s (not the "Photoshop background layer") transparency. Then do a blur on the the locked layer. You should get less spillover at that point. You may also have to use Clay’s method in conjunction with this one.
Clay, I think your response is pretty much the typical text-book solution to this kind of problem. Ive read descriptions of how to deal with this in several books on Photoshop over the last decade or so and that is generally the way all of them have said to do it and from my personal experience, that always provides good results as long as the clone process is done with a careful eye.
Hello
You could cut out the foreground bit and blur the background. Then make a displacement map using the mask of the foreground area (but expanded a bit) to shrink the blurred background.
You will need to fill the expanded mask with a contour gradient(shapeburst) and experiment.
Mike Engles
This sounds a lot like you’re trying to simulate lens blur.
Have you tried using the Lens Blur filter with a alpha channel for the depth data?
I have had good results doing like Clay said, except using the Smudge tool, rather than the Clone Stamp.
Calvin,
If you already have the subject in a separate layer from the background, try selecting the blank space around your subject in the subject layer (you may need to hide the background layer to do this).
Now with the blank space selected, hide the subject and show the background.
Next copy the selected background to a new layer and blur that. (I like gausian blur for that step)
Finally, re-display the subject layer (on top of the blur.) Mike
