Simply put, it is when you combine the sharpest pixels (areas) of 2 or more images to obtain more of your subject in sharp focus than you could with a single exposure.

Examples of when you might use this:

1. Shooting macro when you only have a very small field of focus
2. When you want to keep your background very soft, yet still get a cluster of flowers in focus in the foreground
3. When you can't get a small enough aperture to get what you need in focus

In the example below, I wanted to have both the dead tree and leaves in focus as well as the sky. There was not enough light to do it in one exposure so I took one with the sky in focus and one with the foreground leaves in focus and then used the Auto Align, and Auto Blend features of Photoshop to give me the best of both images.

Sky in focus

Tree in focus

The Process

I began exporting the two images from Lightroom to Photoshop as layers in the same document.  You can do this from Bridge or even from the “Open” command in the File Menu.

This created the image below. One of them was a different pixel dimension and you can see that in the image. Photoshop has no trouble handling that situation, whereas some other stacking programs need the files to be identical in pixel length and width.

With both layers highlighted in the layers panel (see above) Choose Edit>Auto Align Layers.

A dialogue will appear with choices. Leave it at Auto and click OK.

When it is finished aligning the layers, they will appear the same or similar still since they are not yet blended together.  That is the next step.

With both layers still highlighted, select Edit>Auto Blend Layers

A new dialogue will appear with some more choices. Choose “Stack Images” and click the checkbox that says “Seamless Tones and Colors". Hit OK and let Photoshop ingeniously select the sharpest pixels from each image, create layer masks, and leave you with an impressive, all in focus image.

The layers with the intricate layer masks Photoshop used, reveal only the sharpest area of both images.  This is impressive, but think about how impressive it is when you begin to stack 10, 20 or even 30 images!

The Final Image, Cropped And Ready To Upload!

About the Author: Ron Clifford

I am an artist, coach, and creative mentor with a unique gift to help unlock the creative ninja that lives inside every person. You could say what I really do is explore my world through the connections my camera helps me create - and to help others overcome roadblocks and see blind spots along their own creative journey. I have the best job in the whole world. I believe we only truly reach our potential when we learn to help others. To lift each other up. We were made for community and family and in a certain way, that's what I do. I build communities and strengthen bonds through the experience of photography. Nothing can compare to getting involved in building up another person's real life. www.ronclifford.com