Today’s Question: I rarely use the “sky replacement” feature in Photoshop. But, on occasion, I just need to do “something”. I just realized that I can actually take my own photos (of the sky) and use them if I’m so inclined. While I haven’t done this (yet), I like the idea of not having to use and re-use the same, finite skies that Photoshop offers. Can you offer any suggestions for taking and using my own sky photos for this purpose? Would Photoshop be able to use a raw image or would I have to save it in some other format?
Tim’s Quick Answer: For sky replacement images I recommend capturing photos where the sky fills the frame, and with a variety of different configurations and conditions. And yes, you can use a raw capture or other image formats for this purpose.
More Detail: The Sky Replacement command (Edit > Sky Replacement) streamlines the process of replacing the sky in the current image using a different photo that includes the sky. For photographers who are inclined to use this feature, it can be helpful to assemble a library of photos that feature the sky.
There are a few things I would tend to focus on if you set out to capture photos for a library of sky photos to use with the Sky Replacement feature. First, to the extent possible, I recommend filling the frame with the sky, so you don’t have to worry about non-sky areas of the image you’re using showing up in the sky area of the photo you’re applying the adjustment to.
I also recommend capturing a variety of images, both in terms of the overall composition and the sky conditions.
In terms of composition, I suggest having photos captured at various focal lengths, from wide angle to telephoto. You can also vary the angle, such as pointing the lens more toward the horizon versus perhaps straight up. The key is to try to ensure that you have a sky photo that matches the perspective of the sky you’re replacing. You can consider your typical photography habits in this regard to get a sense of whether you should focus on specific focal lengths or perspectives.
It can also be very helpful to have photos that feature the sky with various weather conditions and times of day. It is quite common, for example, to replace a dreary sky with a more dramatic sky. But that doesn’t necessarily mean that you want to focus exclusively on beautiful and colorful sky conditions. If you are replacing the sky in a photo captured during overcast conditions, for example, it won’t look very realistic to replace the sky with a beautiful sunset with scattered clouds, as there will be a mismatch between the color and contrast for the sky versus landscape. You could obviously apply adjustments to the non-sky portion of the image, but even then there may be a clear mismatch.
Keep in mind, by the way, that after replacing the sky using the Sky Replacement feature, you’ll still be able to modify the replacement sky, such as by using the Free Transform command (Edit > Free Transform) to alter the shape and perspective of the sky you’ve added to the image.
