Photoshop: how to mask blurred background

Question

I have a portrait with a blurred background. I'd like to use this to create a mask or for alpha channel or to erase the background.

So after editing I want to have an image with perfect white or transparency where was the background and keep the face unchanged.

Is it possible?

What I tried yet:

• made the image copy
• converted this copy B/W
• made the copy of this B/W layer
• blured this copy
• subtracted these copies:

So I hoped that blurred blur will be almost the same as blur and blurred sharp will differ from sharp parts of the picture. And the difference will be as an indication of the blureness. But I see that my idea did not worked for some reasons.

Any other thoughts?

Answer 1

A little confused about your question: are you attempting to keep the face and remove the existing background? Are you having difficulty making a decent selection?

If the above is correct, you'll want to make a selection of the face.There are a multitude of ways to do that in Photoshop. In this case,you'll want to make a selection of the background. If the background is solid, you could use color range. Otherwise you could make a selection of the face and then use inverse.

I have found the select and mask option invaluable in refining my selections so that I don't have a halo or that pesky little color around the edges. There is a definite learning curve but well worth it.

Once you have made the selection hit "delete" on your keyboard and there you have it! You can then make a new document and do what you want with that background - make it white or transparent.

Hope this helps.

Answer 2

As others pointed out, the best way would be to learn:

1. How to use masks
2. Make and enhance selections in Photoshop

This is THE major first step when learning how to edit an image, beyond the classic and global adjustments, such as contrast, luminosity, curves or B&W conversion.

Concerning your image, Photoshop may have a magic tool to help you:

Select > Focus Area

It automatically select the image areas in focus and can create a selection from it. It is not perfect, but if your background is blurry enough it might do what you want in a single step.

Tutorial on adobe.com: https://helpx.adobe.com/photoshop/using/select-area-focus.html