Max Stacks with Photoshop

Over the past few weeks, we’ve explored the world of Smart Objects, and we’ll continue that exploration here today. However, one special note for today’s lesson – the Smart Object features we’ll be discussing today apply only to Photoshop Extended. If you have only the standard version, read on anyway and let’s explore one of the reasons to upgrade!

With Independence Day looming near in the US, what better topic to pick than creating a fireworks composite? And with Smart Objects, we will find a very fast and powerful way to create interesting composites from multiple shots of fireworks. Now, I’m not going to explain how to photograph fireworks, but I will point you here for a few good tips and I’ll encourage you to look around. Once you have your images, though, we can combine them together to create a whole that is greater than the sum of its parts.

There are two ways to get started:

Method A – Start in Bridge:

For this technique, we will start in Bridge. Pick the images you want to combine, and with the images selected in Bridge, choose Tools > Photoshop > Load Files Into Photoshop Layers…

Bridge will pass the images over to Photoshop, and after a bit of work, you’ll have an image with one layer for each file you had selected in Bridge:

Next, we will want to (optionally) align the images. Photoshop has an automated alignment feature, by choosing Edit > Auto-Align Layers…, but for this type of image I’ve found the results unpredictable. A simpler alignment method may work best, using the Difference Blend method presented here.

Once you have the layers aligned to your satisfaction, we will want to convert all the layers into a Smart Object. Shift-click to select all the layers, then choose Convert to Smart Object from the Layers Panel flyout menu.

Photoshop will take a few seconds or minutes, depending on your image size and the power of your system, but eventually the layers will be combined into a single Smart Object. At this point, we still see only the topmost layer, and the appearance is no different from before.

Method B – Start In Photoshop:

Before we continue, I’ll point out that there is another way to get to this point from within Photoshop. Starting in Photoshop, choose File > Scripts > Load Files Into Stack…

In this technique, Photoshop presents a dialog box that allows you to choose your files, but notice also the checkboxes for alignment, and for creating a Smart Object automatically.

The tradeoff is that searching for the files, and picking the ones you want, isn’t as powerful as working with Bridge. But, this approach can save a few steps, so you have a choice.

Smart Object Stacking

Regardless of which method you use, now it’s time to bring in the Smart Object feature known as the “Stack Mode.” This mode will affect the way layers within a Smart Object layer stack interact, similar to layer blend modes, but with oh, so much more power. Choose Layer > Smart Objects > Stack Mode > Maximum:

Photoshop will have to think a while for this, as there is some amazing math going on in the background. Once it is done, however, the Smart Object layers all appear, overlaid, with all the bright areas from every layer visible:

Note also that the Smart Object layer has a new icon at the right, indicating that the layers are stacked in one of the stacking modes:

You can undo this (and the icon will disappear) by choosing:

Layer > Smart Objects > Stack Mode > None.

The beauty of this technique is you don’t necessarily need to worry about alignment. In this image, I’ve loaded a stack of layers where all but the bottom layer are simply cut out rectangular selections of fireworks shots. I’ve reduced the opacity and added a white stroke to show the locations of each snippet:

If we turn off the stroke, set all the opacities back to 100%, and follow the above Smart Object stacking process, we get this custom-made grand finale image:

I think you get the idea! Now, get out there and try it yourself, and let’s see how you do.

And, what about those other stack modes, the ones with the weird and mysterious names, like “Kurtosis,” “Entropy,” and “Median?” Don’t worry, we’ll explore some of those in a future tip, so check back soon!