As you’d expect from something based on AI and machine learning, Photoshop’s “Sky Replacement” tool is evolving rapidly – less than a year after its debut, the feature just got a big upgrade in the update of August of Photoshop.
But what exactly is the “Sky Replacement” tool and how good is it? Well, if the gray sky and dim mid-winter light sound familiar to you, you’ll know it’s not always easy to get the shot you imagined in your sunny mind.
Reaching a spot in the blazing sun only to find the weather steadily getting worse as soon as you put the camera on a tripod – all of these scenarios are the standard rate for photographers from countries around the world. Have you ever been to Iceland? Let’s go back to our case.
If your landscape photos lack a bit of panache, you have two options: wait patiently for time to cooperate, or accept Photoshop on its unlikely offer which allows you to instantly and photorealistically take your reed gray skies. shotgun and replace them with something a little more jazzy.
Replacing skies in photos has been possible with Photoshop since the early days of the software – mask the sky, tap Delete, insert a new, better-looking one. But the current version of Photoshop and its updated “Sky Replacement” tool are entirely more capable. Not only will it detect, even accurately, where the sky is in your image, it will mask it precisely and automatically and offer you a replacement.
That’s not all: it will also adjust the color balance in the image to match the new sky. An image taken under rain clouds will simply look weird if you fall into a stunning sunset but don’t make any adjustments to the white balance or hues of the original image.
So, without further ado, here’s how it works and most importantly, how to master it.
1. Choose the right image
Not all images in your collection will be great candidates for the Sky Replacement tool. In particular, make sure the image is well exposed. Photoshop will make an effort to change the color balance of your frame, but if the foreground – everything except the sky – has underexposed shadows or overexposed lights, it will struggle.
Some images won’t work at all – most of the options in Photoshop’s sky replacement library are designed to be used with photos taken from a perspective that, in general, is shot perpendicular to the horizon.
So, if you have a photo of a bird, for example, that was taken while tilting your camera towards the sky, you can be sure it will look rather odd, or take a lot of tinkering before you get a presentable shot.
You should also make sure your foreground subject is large – Sky Replacement works great with cityscapes and classically composed rural landscapes, but if you have something small in the frame (a person standing on a hill, for example) he may find he gets unpredictable results.
The good news is that previewing what your photo will look like with Sky Replacement is easy, so you can always open an image and give it a whirl without spending a lot of time and energy. The Sky Replacement tool is located in the “Edit” menu.
Your editing environment is worth thinking about – the discrete results are often the prettiest, so the more carefully your monitor is set up and the more ambient light around it, the more accurately you’ll be able to work. This is especially important if you are going to print anything.
The way the Sky Replacement tool modifies your image is pretty clever: it leaves the original image intact as a locked background layer, then applies a series of masked layers that change the lighting and color of the original, as well as masking the sky in the background.
As long as you save the image as a native PSD, you can exit Photoshop and edit these layers again, although you won’t be able to make any changes to your new sky without repeating the work process through the Sky Replacement dialog.
3. Choose a sky
Now is the time for the fun part. After clicking on Sky Replacement, you will see the relevant dialog box appear.
Basically this is quite easy to use. Click the Sky drop-down box at the top and you’ll see options – many. Luckily, the skies selection is thematically grouped, so “Blue Skies” to brighten the time, “Spectacular” to add some punch, and “Sunset” for those visuals you couldn’t bother waiting for.
It is, of course, worth trying different options. The latest version of Photoshop gives you even more choice thanks to a new menu in the Sky Preset pop-up menu, which takes you to the Adobe Discover site with more options.
Remember, the Sky Replacement tool not only tries to figure out where your horizon is and delete it, it also slightly changes the color balance in the image. Different images will want different skies, so even if you don’t want to get stuck with the sliders and options below, you may still need to kiss a few frogs before landing on the perfect alternative to the original shot.
In its simplest form, the Sky Replacement tool requires two clicks: one to load it from the Edit menu and another to accept the default choice when clicking OK. You have to be careful about making wobbly changes – in the top right image, the dramatic gray clouds don’t really match the blue water at the bottom of the image, betraying the change we made.
4. Make some changes
However, you can definitely fine-tune your replacement sky. Editing begins by simply clicking on the new sky layer – once you’ve grabbed it with the mouse pointer, you can move it, allowing you to place all points of interest exactly where you want them.
If you make changes this way, be aware of the scale slider – this lets you zoom in or out on the sky level, making sure the sky covers the frame from edge to edge.
Photoshop generally does a good job of adjusting the brightness of the original image, but the dialog offers options for fine-tuning. Under the sky adjustments, you can increase or decrease the sky exposure, as well as heat or cool the color temperature to match the original image.
Below the foreground adjustments you get a similar pair of sliders. Our suggestion is to use both of them at the same time and try to make them “meet in the middle” to produce a photorealistic effect. You’ll have a better chance of getting things exactly right if the original image is technically good – for example, not over or underexposed and with the correct white balance.
You can also fine-tune the area of the image where the skyline meets the new sky. For that, click on the magnifying glass in the Sky Replacement dialog or use CMD + to zoom in. Work at 100% or even 200% and carefully scan along the skyline to see if there are any choppy-looking bits that Photoshop got it wrong.
In our experience, the Sky Replacement tool does a remarkably accurate job, but if you find something that looks iffy, press B to select Sky Brush and paint in more sky by clicking and dragging.
5. Finishing touches
Happy with your new image? You have to make another choice before you go: if you want your effect to be applied to a single new layer or as a series of adjustment masks and adjustment layers, in the “Output in” drop-down box. Whichever you choose, the original image will be preserved as a locked background layer. If you think you want to go back to the image and edit the sky later, choose New Layers.
Once this is done, the new layer called Sky contains the new sky and can be transformed, enlarged, reduced, and so on in the same way as any other layer in Photoshop. It also has the cropped mask of your skyline. Again, this can be changed in the same way as any other mask.
The layer called Foreground Lighting is a mixed layer that changes the brightness of the original foreground image, while the Foreground Color layer is the one that attempts to match the chosen sky with the foreground. Again, all of these layers can be edited like any other Photoshop layer, including their opacity, blend mode, and so on.
There are a ton of tweaks you can still do to make things perfect. Almost the only thing that I can not To do is go back to the Replacement Sky dialog and edit the original effect, but with the original image still intact, you can always duplicate it (CMD-J), group the rest of the replacement sky and hide it and start all over again.