Selectively apply feather in Select and Mask

Question

I’ve never been much of a Photoshop wizard (InDesign is my domain), but I do edit images to be used things I typeset. This frequently includes removing backgrounds from images to get sharper illustrations, for which I tend to use Select and Mask.

Generally, the sharper the edge the better – but sometimes, the artwork fades into the background, and a fading effect is then obviously desired instead. If the entire artwork fades out more or less evenly, this is usually not a problem: just give the selection an appropriate feather in Select and Mask, and your layer mask will have a nice, gradual fade-to-transparent effect which is enough for most cases.

This doesn’t work so well if the fadeout is only in a part of the image, though.

Say the image is a scanned drawing of a military medal on a ribbon. The objective is to use it in some document without having a sort of greyish overlay where the paper isn’t quite white in the scan. The edges of the medal itself and the sides of the ribbons are sharp, so they’re easy enough to mask, but the top of the drawing ends in the ribbons being drawn to fade out into paper colour, and the layer mask should reflect this, so that the top of the ribbons fade to transparent.

Is there a relatively straightforward way to achieve this, applying the desired feathering to specific parts of the selection while maintaining sharp edges for the rest of the selection, preferably within Select and Mask mode?

Answer 1

You can do this no matter how you generate your initial mask, the trick is only that you do the fade on the mask after you auto-generated it.

Use the magic wand or 'select subject' to isolate your medal & ribbon.
From the Layer menu > Layer Mask > Reveal Selection.
This will add a mask to your background to hide it

Select the mask in Layers

Use a big, soft brush, colour black.
Swipe across the desired 'fade out' area.
The size of the brush will determine how the softness affects the fade. This is just a single sweep at 100%, from just off the edge of the overall image.

If you need this to work also on a dark background, I'd be tempted to just hit the fade harder, unless you are limited in how far you can go.
I re-did this with a fade to white on the original as a quick 'paper simulation', then dropped a black background under it. Less satisfying, but you might get away with it.

^{I noticed after the fact that I didn't do my initial selection carefully enough, I punched a hole in the medal;)}