LMAC School - How to add rays of light
Whether it is an alien laser beam, a ray of sunshine through a window or the beam of a flashlight, light rays are a little challenge in photo collages and photo montages.
In this tutorial, I'll show you some ideas of creating light rays and, using a few examples, how to implement it.
Warning - Internet bandwidth:
A lot of GIFs are used for explanation in this post. If you have a very slow internet connection please leave me a message. Then I will make this post available compressed in a ZIP file.
You may need the GIMP software to understand this tutorial. GIMP is a free, open source tool for image processing of all kinds. Lots of people say GIMP is the open source Photoshop. I agree with this statement at least for the functionality I personally need.
You can download GIMP here: Click
I created this tutorial for GIMP version 2.10.20 (and higher).
We will work with layers in this tutorial. If you do not know how to work with layers, just take a look into the LMAC School - How to work with layers post.
Before I get into the how-to, let's take a closer look at light rays in the nature and what different kind of rays exist. Because when we become aware of the details, we can achieve more realistic effects when we depict rays in our works.
A laser beam is extremely concentrated light that is emitted in a focused manner by its light source. The light waves in a laser beam are all from the same color.
An important property of lasers is the strong focus of the generated light beam and the respective low intensity loss in the distance. This means that a laser beam barely appears wider at short distances than at the starting point. This also applies to the strength of the light itself. Over greater distances (miles), however, a difference in width and strength can be determined. How strong this effect is depends on the strength of the laser itself.
How strongly a laser beam is visible and looks translucent in a photo also depends on the strength of the laser, but also on the strength of the ambient light compared to the laser strength and the densitity of the medium (air, water, etc). The lower the density of the medium, the less visible the beam is. Because the beam becomes visible through reflections from particles, molecules in the medium.
Any film that shows laser beams in space is just wrong. There is hardly any reflective material in space that a laser beam can pass to get reflected as a result.
Rays of sunlight or strips of light that come from the sun and in most cases shine through clouds are more precisely not really rays in a physical meaning, but bundles of light. The course of the light becomes visible through the scattering in the air.
When the sun is low, they are shown most clearly. Then they can extend almost over the whole sky.
They are actually not that rare.
We know a similar effect from dusty rooms or saunas into which the light shines through the window. The rays become there visible because the incident light is reflected by particles in the air.
Both types of sunlight have two things in common. Over the distance they stretch out in length, the light cone get wider towards the end. And on the other hand, the more reflective material there is in the air, the more visible the respective ray (water droplets, dust).
In fact, the light from flashlights is not always visible. Just like the rays of sunlight, they only become visible through particles in the air.
And just like the rays of sunlight, the beam of a flashlight is conical.
However, at the end of this cone, where the beam hits a surface, there is the specialty of the flashlight light. Because there the beam depicts a so called Light Cookie.
The Light Cookies looks a little different for each flashlight model. Older models with incandescent lamps usually have a clearer Light Cookie. Younger models with LEDs, on the other hand, usually project a soft, bright circle.
Most lamps these days have a cover, whether they are indoors or outdoors.
Such cover mostly works more or less as diffuser that diffuses the light. The light cone of such a lamp appears smooth and to a certain extent undefined.
Sometimes the light is also scattered radially around the lamp body. Fog and air humidity or other particles are also decisive for the direct visibility of such radiation.
Now we are once again aware of the properties of different light ray effects. So it is time to show you in the examples below, how to implement the different kinds of rays into your photo works.
Hint: You may want to add some haze or dust before you start working on the sun's rays. Then these types of rays appear more natural.
You can easily paint this on your canvas with a white brush, with low hardness and low force.
Flashlight beams can be made using the same methods that we used for sunlight rays and the laser.
It depends on the requirements of your scene which method is suitable.
One difficulty, however, is the Light Cookie that the beam projects onto surfaces.
There are a lot of usable Light Cookie textures on the internet. But you can also use mine.
It imitates the projection of the glass lense of a flashlight.
How-To:
We skip the first steps that you already know from the laser and sunlight ray.
So let's start with placing this Light Cookie onto a wall, on a prepared canvas.
In this example I show one way how to illuminate a lamp with diffuse light. Instead of a defined beam, I put a ball of light on the lamp, so that it looks like it's shining brightly.
In addition, I will show you a way how to solve the lighting of the background.
I used a lot of artwork for the animations and illustrations. Most of the material is sourced from Pixabay and is free for any use.
Only the light cookie and the light cookie photographs are my own materials.
Best regards
QuantumG
PS: 33% of the rewards for this post go to LMAC as beneficiary ( #supportlmac ).
You will have noticed that I am not a native English speaker. Therefore, there are probably a few linguistic bumps in my texts. If there are any passages that could trigger accidently a world war or something similar, please let me know so I can change it. :-)
Of course, I am also interested in making the text easier to understand if it is partially necessary.
