View single post by Eric
 Posted: Sun Feb 21st, 2021 06:24
Eric



Joined: Thu Apr 19th, 2012
Location: United Kingdom
Posts: 4424
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Eric wrote:
My desktop is out of action at the moment (lack of use) but will see if I can find it elsewhere on a drive.

From 15year memory.......
The process started with tight masking ALL the areas behind the subject.
Apply a minimal blur as the 'base coat' start this action..

Contract the mask by 2 pixels > Apply a feather of 1 pixel > Apply 5% more blur
Contract the mask by 4 pixels > Apply a feather of 2 pixel > Apply 5% more blur
Contract the mask by 10 pixels > Apply a feather of 5 pixel > Apply 10% more blur
Contract the mask by 20 pixels > Apply a feather of 10 pixel > Apply 10% more blur
Contract the mask by 50 pixels > Apply a feather of 20 pixel > Apply 15% more blur
Contract the mask by 100 pixels > Apply a feather of 50pixel > Apply 20% more blur

The actual numbers may be wrong but the principal is the same.....ie don't apply feather to the mask in the first instance, then soften the edge effect by 'one step forward - half back' approach, increasing the intensity as you go further back.

There are a couple of pitfalls to watch out for. 
The mask moves away from the frame edges incrementally so you are left with an edge and top that needs a small crop.
If the mask is not horizontal behind the subject lower areas may get more blurring than their distance demands. So using the rectangle mask to subtract these irregularities halfway through the action (or step back afterwards and restart)  irons out this issue.

Of course Adobe may have added this filter to more recent versions ....but I am still old school diy.

NB Save the original mask before you start the action so you can reapply it if you need to redo it.



____________________
Eric