In this video, we'll see how to use the Mix 1 mode of the Glare post-production node in Blender to isolate and adjust the glow separately before adding it back to the original image. Among other things, we'll see how to direct the Glare; how to make it larger, brighter, and how to give a color tint to its outer parts.
Video Transcript
Hello everyone! In this video, we'll see how to use the Mix 1 mode of the Glare post-production node in Blender to isolate and adjust the glow separately before adding it back to the original image. Among other things, we'll see how to direct the Glare; how to make it larger, brighter, and how to give a color tint to its outer parts.
This tutorial was recorded using Blender 4.1, but the Glare node has been available for several versions of Blender, although it was previously grouped differently in the Add menu.
As you may know, the Glare filter allows applying various types of glows to the input image; in this version of Blender, the available effects are Fog Glow, Ghosts, Streaks, and Simple Star.
The effect is applied to the parts of the image where the intensity is greater than the value specified in the Threshold parameter.
By default, this parameter has the maximum value, which is 1, so normally the effect is applied to the brightest areas of the image only. Therefore, usually the first thing to do is to lower it. In the scene I'm using, I'm setting it to 0.95.
The output of the node, when the Mix parameter is set to 0, is the input image with the effect already applied.
However, if we set the Mix parameter of the node to 1, we get the effect alone, isolated on a black background.
The result is similar to what can be achieved with other nodes set up in order to mask some parts of the image or perform threshold operations, such as a Color Mix node in Subtract mode, but there are differences in the values returned, as well as the fact that the output of Glare includes the effect specific to the node.
Anyway, isolating the effect allows us to modify it before applying it to the original image, which we can do with a Color Mix node in Add mode, making sure to connect the output of Glare to the second input of the Mix node.
Some immediate operations include, for example, the possibility of enlarging the glow, for instance with a Blur node. We can also use Dilate Erode or other nodes before Blur, to enlarge the mask before blurring it.
It's also possible to increase the intensity of the effect, for example by using an RGB Curves node, setting the C curve in a way that resembles a Gamma curve, to avoid clamping some values to 0 or 1.
Using the RGB Curves node, it's also possible, of course, to provide a color tint to the glow.
You can also use other tools to try to direct the glow, for example by using the Sun Beams node, which I've described in a couple of video tutorials previously published on my channel.
Finally, nothing prevents us, from using multiple Glare filters, modifying them differently, and then adding them to a single render. Let's see an example of what I just said.
First, after rendering the scene, I connect a Glare node to the Render Layers' Image output, setting the Glare node with a 0.95 threshold, Fog Glow mode, and size set to 9, to provide a first glow to the spotlights, then setting Mix to 1 to isolate this glow and modify it separately.
At the output of Glare, I connect a Sun Beams node, placing it in this case in the top left corner of the render, so as to direct the light beam towards the opposite corner.
Next, I connect two different Blur nodes, in Fast Gaussian mode, to the output of the Sun Beams node. The first Blur node will have a higher blur value, for example, 75 pixels, which I'll colorize to provide a wider, more diffused glow with a tint of color to the lights. The second Blur node will have a lower blur value, such as 25; combined with the first, this second Blur node will intensify the central part of the light beam.
As mentioned earlier, I connect an RGB Curve node to the first Blur node, changing its color using the color curves. In order to achieve a visually more pronounced effect, I'm using a shade of blue... which... might not make much sense, actually... but this way the color will stand out more against the warm tone of the rest of the render.
I then combine the two effects using a Color Mix node in Add mode with the Factor parameter set to 1.
On the second Blur node, which has a lower blurring value, I haven't applied any effect, but there's nothing preventing us, for example, from making its brightness more intense using another RGB Curves node, this time modifying the C curve, or by using other effects.
To observe the effect obtained at this point applied to the initial render, I add the node setup created so far to the image coming from Render Layer using another Color Mix node in Add mode.
To complete the setup, I add a simple final vignetting effect by multiplying the composite obtained so far with an oval white mask on a black background, with blurred edges, using an Ellipse Mask node in additive mode and a Blur node.
Well, that's all for this short tutorial! I hope it was helpful! See you soon!