With fancy dual and triple camera phones, you can set the depth of field of your images using a simple slider. But did you know you can do it in Photoshop, too, after you’ve taken the photo? Colin Smith of photoshopCAFE figured out a way to refocus images in Photoshop after they were shot, and he’s sharing it with you in his latest video tutorial.
Colin captured a photo with iPhone XS and a Lightroom Mobile Camera, so a depth map was created inside Lightroom. This is kinda limiting for us with single-camera phones, as you need a dual or triple camera phone for this. But, as Colin points out, phones like this will be a standard in near future. So, here’s the process of refocusing your image after it was taken.
First, you need to open your photo in Lightroom. Go to the Develop module, grab the Brush tool, make it small and just tap it somewhere in the corner. Then, go to Features> Range Mask > Depth, and you’ll have the depth map shown.
Now, the tricky part is that the depth map won’t show if you take the image to Photoshop. So Colin figured out how to bypass this – with a simple screenshot. So, take a screen capture of your image with the depth map shown. From here on, you’ll move to Photoshop.
Start by opening your original image in Photoshop. Go to File > Place Embedded and select the screenshot you previously made. Stretch it so it fits the original image, hit Ctrl/Cmd + A to select all and Ctrl/Cmd + C to copy.
Now select the original image and go to Channels. Create a new channel and hit Ctrl/Cmd + V to paste your depth map.
When you look at the map, it tells you that everything that is bright is closer to the camera, whereas everything that is dark is further away from it. You can turn this around by selecting the RGB channels, omitting the Alpha 1 channel you created. Go to Filter > Blur > Lens Blur and under the settings go to Source and select Alpha 1.
If you adjust the lens blur settings, you’ll notice that the foreground gets blurred out, while the background remains sharp. But as you move the Blur Focal Distance slider to the right, you’ll notice that the foreground gets sharp, while the background gets blurry. Pretty cool, isn’t it?