Monday, October 21, 2013

Week 5 - (Fundamentals)

To recap on last week, I was testing out different light sources of Maya and experimenting with their attributes. From it I was able to get a basic understanding of how different lights work in Maya. 

This week’s focus was on the actual theory behind lighting and light rigging itself. Rather than just focusing on CGI lighting I chose to look into other forms of media. This included; film, photography and even old paintings as lighting had been a thoroughly researched topic in these fields. Not to mention they were using actual light that gave natural results (rather than just programed).

The actual challenge is trying to create believable lighting within the capabilities of Maya. It much simpler to have bad lighting in a computer program than it is real life. Some things can easily just be seen as ‘out of place’, ‘too bright’ etc. A knowledge of how real lighting works can be transferred to Maya and give believable results that are replicated in real life. There are advantages and disadvantages through the program but for now my focus is on observation. 

Factors of good lighting

"Good lighting is important for quality video in three different ways: exposure. Illusion of depth and mood/feeling", (Jackman, 2010)

This was probably the more basic way of summing up production lighting that I understood. The three factors it address’s (exposure, illusion of depth and mood/feeling) are all needed when setting up shots.

Exposure is the visibility of a shot. How lit the overall areas of the shot are and what details and forms are shown. Having not enough exposure on a shot causes dark hard to read visuals, whilst over exposure blows out whiteness. 

Illusion of depth is simulating 3D space within an environment. Even though a camera can capture real life, the actual viewing of the material is only in a 2D surface. Having depth in a scene tricks the viewer into thinking (or rather reinforcing) there is depth in the shot. 

Mood and feeling help give a soul/deeper meaning to the shot. This could be highlighting something or telling us something about the character/object. Having this brings a shot out of realism and more into creative, artistic and semiotic communication.   

Lighting in traditional work  

To start initial research on light I looked into old paintings that had a direct demonstration in the subject of light. It was an interesting direction to take the research as light was being understood in art before film and photography. The Painting that I ended up looking at was Claude Monet's series of haystacks. From looking at the pictures there is a rapid change in the tone and colour. The haystacks are basically the same but painted at different times of day and weather. What can be learned from this is the dramatic changes natural lighting can have on objects. How the different lighting can give off alternate moods and behaviors.  

Lighting Rigs

High key lighting
High key lighting is a two light set-up of both a key light and a fill light. They both are angled in the front of the shot with the fill light having near the same intensity as the key. This results in everything being evenly lit and at a higher intensity. With the extra dimension of colour forms are separated and readable (unless if you are colour blind). The advantage behind this system is that it is simple and it works. The negative is that it creates a wash of light that makes shots look flat and is bland.  

3 point light system

Out of all the research I was able to do for this week the 3 point light system seemed to be the most commonly written about light rig. Though you couldn't really blame it considering of how much of a effective staple it is to lighting. It order to produce the 3 point light system you place a light angled on one side of the camera focusing on the asset/area. This is the dominate light source and is known as the key light. On the other side of the camera is another light but with much less intensity. The light, known as the fill light, exposes the areas which the key light would leave in darkness. Having the light at less intensity creates light tone and contrast that helps bring out details. Finally the is a light placed at the back of the asset/area. With the light, or rim light, protruding off, the asset/area creates a highlight that helps give a sense of depth within the shot.  

Light bounce

This isn't so much of a rig as it is a technique. When we have an existing 3 point light system an extra key and fill light can be added to control bounced light on an object. The secondary lights will be in line vertically with their duplicates and have greatly lowered intensity. This adds brightness to the lower part of an object simulating light that has bounced from the ground. A slight change but a definitely noticeable adjustment.

Building light plans

When it comes to lighting for environments it's a good idea to produce a draw plan first of where the lights may go/where you need lighting. 

Unfortunately I couldn't exactly find any kind of formulaic environment light rig. However with the varied location choices it would only seem silly for there to be a one all rig for environments. I did however find a process in developing them. 

 Primary light source - Add lights and attributes of those lights that would come naturally to the shot being created. This would be though sunlight or artificial light, like lamps.  

Lights focused on active areas - Giving extra or special consideration for lighting where the actual action may take place. If the camera is focusing on a character, they should have more lighting focus to them. 

Lights to expose and give depth - Creating a focal point to expose  then adjust the rest of the shot according. 

Set lights properly - Basically as it says. placing the lights that have been planned.

Watch shadows - Have control over the shadows. Make sure no odd shadows are intersecting weirdly with the action of the shot. A shadow is a form.

Accent lighting, interesting light structure - Breaking up spaces with lights and shadows to create more interesting visuals.

Fill lights - Filling up all the darkness that would be otherwise caused by the original key lights.  
Shadows giving sense of depth - Manipulating shadows whether it be adjusting for more realism or creative lighting.

Eliminate hot spots - Areas that may have a fairly strong lit area that are out of place in the shot. The previous steps reduce that happening. However if there is movement in the scene the lights may need to be adjusted accordingly.

This is obviously more focused towards film production , however the techniques themselves transfer directly to CGI.

Other useful stuff I discovered whilst researching light
Barn doors - controls aperture of light
Mirror ball - shows overall lighting of scene

Probably finishing this on a rough note but for some reason I writing too much from what I have intended. There has just been so much information to learn. I could probably adjust the scope of the research but I still really want to focus on efficient environmental light rigging.

Jackman, J.(2010). Lighting for Digital Video and Television. (3rd edition).Oxford, UK: Focal Press
Parrish, David A.(2002). Inspired 3D lighting and compositing. (1st edition).Great Britain : Premier Press
Unknown. (2013). Turner to Monet. [Online] Available [October 22nd 2013]


Ashton, K. (2011). Studio Lighting Techniques. [Online] Available [October 27th 2011]
Ball, A. (Producer), & Mendes, S. (Director).(1999). American Beauty [Motion picture]. American: Dreamworks.
Feringa, B. (2013). Bert Feringa Blog. [Online] Available [March 29th 2013]
Unknown. (2012). Light Your Video. [Online] Available [May 4th 2012]

No comments:

Post a Comment