Combining A Layer Mask Selection with Layer mask Gradient

[Chrisn N]

I am wondering if there is a way to apply a gradient  to an existing layer mask that already has a selection without deleting the selection. Maybe another gradient can be cliped to an existing layer mask?

For example. 

1- Make a duplicate layer, use a layer mask to select the background of the subject and blur it. The result is that all of the background will be blurred making the subject stand out.

2.If its possible,  apply a gradient to the  layer mask so that only distant objects will be very blurred and nearby objects less blurred.

I know this can be done if just the background is copied to a separate layer using control + J.Then a gradient can be applied to a layer mask. 

But what about the situation where the layer mask has the selection of the background? Applying a gradient will remove the selection of the background that is already on the layer mask. 

Your advice would be appreciated.

Kind regards

Chris

[Jeff Arola]

Instead of a gradient you could use Filter>Blur>Lens Blur and select Layer Mask as the Depth Map Source.

https://helpx.adobe.com/photoshop/using/adjusting-image-sharpness-blur.html

Like this

1. Click on the pixel layer to make sure it's selected and not the layer mask

2. Shift click on the layer mask to disable it

3. Go to Filter>Blur>Lens Blur and under Depth Map Source select Layer Mask, then adjust the sliders as desired for a      blurred background

[Chrisn N]

Thank you very much Jeff. I didn't know about this technique. I have learn't something new! I will keep this method in mind for future edits. This will work great in situations where I need to blur all of the background like in the example of your flower photo. 

However, this technique will not work on the image I am working on, which is a wild sheep on the side of a mountain. I need to selectively blur distant scenery and keep the foreground near the sheep unblurred. I have found a solution by cutting out the background to a new layer, blurring it and applying a gradient mask so that the sharpness in the original image will show up on the layer underneath. Another way would be to use your method and use the brush tool on a layer mask to progressively paint out the blur on foregrouned so the sharpness in the original image will show up. 

My main question is if there war to apply a gradient to an already existing selection on a layer mask. A bit like combining or clipping two layer masks so that I can get a gradient effect on a selection that is already there on the layer mask. 

Kind regards

Chris