Is there a difference between blending and compositing in post-processing? Some make no distinction between the two. But some do. Let’s have a closer look!
I’ve spoken to a number of photographers about blending and compositing. To my surprise, some photographers, especially if they do not do much night photography, do not make a distinction between blending and compositing. I’m going to describe how most night photographers use the two terms.
Compositing
A composite is when you combine elements from two different photos into a single image. An obvious instance of this is if you use a program such as Photoshop or Luminar to replace a bland sky with a dramatic sky. This is often done in landscape or real estate photography.
Compositing is also done often in night photography. A photographer might take a really nice photo of the Milky Way from one night and mix it with a landscape photo taken on another night. It’s possible to take a photo of a Milky Way in Utah and add it to a landscape photo of Arizona. Conceptually, it’s similar to someone cutting out a picture of a person from one magazine and pasting it on to another picture, only considerably more sophisticated (hopefully).
Blending
One of the most well-known methods of blending is HDR blending. This is where you might fix your camera to a tripod and take several different exposures of that same scene in succession. Then in post-processing, you would blend those multiple exposures together into a single image. The goal is to render the scene but with a high dynamic range.
For a night photographer, blending is not altogether different. You are taking photos in succession with the same tripod, camera and lens setup around the same time. Like HDR, it’s still bracketing. It just takes place over a longer period of time.
Examples of how a night photographer might blend photos
Notice how each of them bear some resemblance to HDR in that they are often controlling some aspect of dynamic range.
- Taking a very long exposure low ISO photo of the landscape. After that, taking a shorter exposure high ISO photo of the Milky Way. The first photo may or may not involve light painting as well. The low ISO image is an effective way of keeping the noise level down.
- Taking a “blue hour” or moonlit landscape. After that, waiting a while with the camera and lens in the same place to photograph the Milky Way.
- Blending several photos over time to show the passage of time, only in one image. For example, you could show the transition between sunset to “blue hour,” or somewhat like above, the transition of “blue hour” into night.
The philosophy between compositing and blending
With compositing, you are taking different elements from different photos, then combining them together to create art.
With blending, you are doing so to address dynamic range and limitations of the camera to try to recreate what you see and experience.
The difference between compositing and blending can be fuzzy. Both can look somewhat similar if you are watching someone post-process. But I believe there’s enough fundamental difference to distinguish between the two. Certainly, night photographers seem to feel this way.
I almost never do compositing of night photos. I believe I’ve only done one or two. However, I have no issues with compositing. For night photography, I would prefer if the artist were up front about composites.
However, it really is all art. Compositing, HDR blending, blending to show long passages of time and photography are all different forms of art. Some attempt to recreate how it looked or felt to be there while others attempt to create a fantasy image. And like all art, some might appeal to you while others might wrinkle your nose in disgust. Beauty, after all, is in the eye of the beholder.
What are your opinions on what constitutes composites or blending? Or for that matter, what constitutes photography and what falls into the realm of digital art? Let us know in the comments below.
And if someone doesn’t like compositing or blending, they’re really not going to like AI art, like you described in another recent article.
I really enjoy your art and articles Ken.
Thanks
Thank you.
And maybe not. Or not a lot? I mean, I use blending to make the image look cleaner and have less noise and no other reason, and I use HDR to make things look much more like what I see in person, so they might like that?? ¯\_(ツ)_/¯
Great article. Blending overcomes technical difficulties in showcasing a dynamic scene where as compositing is essentially creating something from nothing. I’m not sure how adding a night sky to a daytime photo (what is being expressed by the artist?) is art but to each their own.
Thanks, Matt. And agreed.
I don’t know about the last one. It’s not something that interests me, but perhaps there’s a cool artistic reason.
I know this isn’t quite what you mean, but I do enjoy those photos that gradually shift from day to night as you go from left to right. I keep meaning to do something like that someday but that requires some seeious commitment and time!!
Keep up the great work with your podcast!
They are techniques of a complex art, like the techniques of all the figurative arts that tend to show what comes from personal feeling. It is not the technical gesture that, although fundamental, is its knowledge, but what is expressed thanks to it too. Great article Ken, thank you very much.
Ideally, yes. Personal feeling, emotion, and clarity of vision should inform any technical decision in a perfect world. Including using the various ways of handling dynamic range. Thanks for the kind words, Stefano!