How to set up bloom in Unity

Question

Last time I used image effects in Unity it was back when 3.0 was released and for bloom you used the object's alpha to indicate whether it should glow or not. Now in 4.2 I couldn't grasp how to apply the image effect properly. It seemed to put the whole scene to glow and alpha did not affect it.

There was no help from the Unity docs which are pretty much just spec sheets for the effects and no proper tutorials around. This leads to couple of questions:

1. How do you create something like the screenshots in the Bloom page in the docs? Only the car windows and metal parts glow, but no glow on the concrete.

2. How do you make a light source like the second image on the above link? I tried different shaders and lights on a gameobject but none of them produced anything like that.

3. What does the HDR checkbox in the camera actually do?

Answer 1

0.) Setup

Since the Release of Unity 5, Bloom (and quite a few other Image effects eg Ambient Occlusion, Blur, Color Correction etc) have also become available to Personal (Non-Pro/Non-Paid) Users.

To start you need to import the Effects Package into your project: Assets -> Import Package -> Effects

Once you've imported this package you will see the "Standard Assets" folder in your Project Tab, within it will be a sub-folder "Image Effects" where you will find C# scripts named appropriately after their effects. Simply drag and drop the Bloom.cs script (or any other image effects you want) onto the camera you want to apply them to.

If for some reason you don't have the Standard Assets Package installed in your platform you will need to either include that manually or first upgrade your project to become Unity 5 Compatible.

1. & 2.) Specular Mapping

Specular Shader Documentation

This image you are referencing is utilizing Diffuse and Specular materials as well as Specular mapped shaders. These allow you to define the areas of a model / mesh that will reflect or absorb light. In its simplest form you chose whats shiny and whats not. In combination with the Bloom Effect, correct Lighting / Intensity and HDR (High Dynamic Range Rendering) camera attribute seen in that image, you could achieve a similar appearance.

To achieve the effect you want, you probably aren't even looking for the Bloom effect at all. You just need:

1. Specular & Diffuse Materials -to accurately apply a Specular Map your materials to define some as "Shiny" and others as "Flat" / "Diffuse". Concrete is a non reflective Diffuse material, while the glass a fully reflective Specular.
2. Higher Intensity Light - Do this in conjunction with a more powerful light source, a Directional light often is suitable when trying to emulate the sun for outdoor modeling.
3. Reflection Probes (optional) - These may not be necessary but when I am dealing with Specular / Metallic materials and the Standard Shader these can go a long way!

3.) High Dynamic Range

In photography HDR is a technique used to attempt to composite multiple images in order to increase the range of "Light" or "Luminosity" that can be seen. This is an artistic technique to make images more vivid or dramatic then we perceive those scenes in real life. As humans (I am assuming we're all human here) our eyes attempt to adjust to the lighting conditions surrounding us, restricting or increasing the level of light intake. So in effect our eyes adjust the range of light we perceive based on the overall lighting conditions.

How it works: When we read HDR, we are assuming a process of taking multiple "photos" or "passes" at a single shot/frame with multiple light settings (at minimum three: low, medium, high; sometimes many more) and composting the data together into something more. See below for a normal shot and a HDR composite: