Why do you need Photoshop Layers and Masks?

St. Mary Falls, Glacier National Park, Montana (MT), USA

We are often asked why we need to understand Layers & Masks in Photoshop? After all, we can always blend or adjust images using HDR software, right? Here’s a quick explanation.

Overexposed Highlights

After iHDR Blend

Take a look at the two images above. Notice that the highlights in the image on the left are overexposed. You can’t see any detail in the white areas in the water. In the second image, I corrected the overexposure with our iHDR workflow. I can create a similar blend using an automated HDR tool. But this is not a finished image. I want to take it further. I think the image needs some corrections to improve the contrast in the rocks, and to help focus the viewers attention on the water itself. To accomplish this, I used different layers and masks to limit each adjustments to a specific region. The image below show all the layers and masks I used, and the areas I targeted with each adjustment.

Adjustment Layers and Masks

It is true that I can accomplish the same adjustment without layers and masks in Photoshop, but adjustment layers combined with masks allow me a lot more freedom. I can fine-tune the adjustments I made on each layer without destroying the other layers. I can make adjustments to a single layer without having to retrace my steps. I can turn layers on and off to see what effect they have on one another. And I can add to or subtract from each mask to refine it at any time during the workflow.

I often save the image as a PSD file – with all those layers and masks intact – and return to it a few days later. In this way, I can keep track of all the adjustments I’ve made.

So, layers and masks let me take my blended image to the next level, and they allow me to preserve the processing steps I used to create the image. As my workflow gets more complex, layers and masks allow me to keep track of each adjustment, and gives me much greater control.

To learn more about Layers and Masks, check out Session 2 of our Nature Photography and iHDR Workflow Recording: Histograms and RAW Processing