Some creative endeavours are quite difficult to achieve and like some occupations or careers, you have to make a large initial investment in both time and patience before you can extract any acceptable level of output.   If you want to be a reasonable violinist you must practice almost every day for at least one hour over a period of six or seven years in order to get to a level where you could be considered a reasonable amateur player.  Learning to animate using Maya, however, does not need quite the same commitment as the violin.  The more you practice the better you will become but unlike the violin, the computer should help you get reasonable results within a relatively short time.  The computer allows you to experiment and by trial and error you can hone your animation toward reasonable outcomes.   Obviously, you will need to know how to handle a PC and be familiar with how to navigate and manage the filing system.   You will need to know how to navigate around the Maya application and be familiar with the main geometry windows, the outliner, the graph editor, the channel box and the time line.   You need very little else to be able to learn technique in Maya but you will, like everything else, need plenty of patience.

The capabilities of the computer and of the Maya package that lie at your finger tips are endless; from producing realistic dinosaurs that roam around the earth millions of years ago, to fantastic characters that populate J.R.R. Tolkienís books, to a myriad of other entities that can be created within this amazing virtual environment.   Only our imagination limits what we can finally produce, but time, patience and technique are also our allies.
Familiarise yourself with the motion around you.  
Look at the world with your special eye for motion analysis.  When you spot that poor pigeon in the street, that thought there was some bread when it landed but is now confused because it no longer seems to be there, don't walk by.   Stop and have a good look and take mental notes of the movement.   How does he turn his head?   When does he blink?   How is he reacting to things around him?
Observe the details and the bigger motion picture will form from these.

In what way does a mouse run?
In what way does a tree sway in the wind?
In what way does a man without teeth talk?
In what way does a JCB shift its weight when taking up load?
In what way does a dust bin roll around in the wind?

All these examples and more can be helpful, but if you have a specific case that you wish to animate then have a look on line for any reference footage that could be useful.   If the entity you are animating does not exist then find the nearest thing to it.

Handling the Timing Element.
Animation can be described as a series of events strung out along the time line rather like socks on a washing line.   In Maya these events are defined as keys which, unlike socks, hold a numerical value for a certain parameter at a certain time.   The values for a chain of these keys are important but the spacing between these values is critical.   The amount of time that you allocate between events / keys will determine the whole outcome of your motion.   As in music, your keys should be laid out like notes in meaningful groups and clusters and, where possible, within a natural rhythmical structure.
The way in which you manipulate these rhythms and the spaces (like musical rests) that you place between events or event groups gives your animation the structure that carries the motion through to your audience.   Your audience has benefited from millions of years of evolution and their eyes and brain have been highly tuned to detect all sorts of visual stimuli including motion and rhythm.   As sophisticated as the human eye is, however, it does have many restrictions.   Some of these you can take advantage of but others obstruct the communication of your motion.

I had the honour of interviewing Professor Richard Gregory while researching a programme about the senses for Channel 4. Gregory, an experimental psychologist, was one of the greatest authorities in visual perception.   He explained to me first hand that the human eye, the visual cortex, that is the bit in the brain that receives the signals from the eye and the tube that joins them, the optic nerve, are far more complex in operation than you may imagine.   The assumption is that because your retina, that is the light sensitive surface at the back of the eye, is made up of around five million cones (colour receptors) and around a hundred million rods (luminance receptors) that the brain has a pair of vast mega pixel cameras on which it can rely for converting the moving colourful world into meaningful visual sense.   Unfortunately, the optic nerve is not quite so impressive and is restricted to around one meg of active channels. According to Gregory, if the optic nerve was to carry signals from all rods and all cones then this nerve would be so thick, the eye would be unable to turn in the socket and thus defeat one of its merits.   Gregory stated that a great deal of retinal content is pre-processed and multiplexed before being sent down the nerve to the brain.   He also implies that some movement, along with other specific entities like verticals, horizontals and diagonals are detected at retinal level by communities of rods which are then processed and sent as a simple flagged warning to the brain.   It is this processing that evidently accounts for the speed of reaction to some visual stimuli.   If all visual signals were left to the visual cortex to analyse properly, our reactions would be too slow and we, as a species, would never have been able to survive the hostile world of our ancestors.

Regretfully, Richard Gregory died in May 2010 at the age of eighty six.

Taking Advantage.
These eye/brain restrictions can be taken advantage of by the animator.   The most obvious one is that a series of sequential still images, if presented to the human eye in quick succession at around 16 images a second, will appear to merge into a coherent moving entity which is a perceptual illusion called "Beta Movement" (defined by a chap called Max Wertheimer).   Thank goodness for that, else we might all be out of a job.   I was under a delusion, in my younger days, that "Persistence of Vision" was something to do with it but it is evidently not the case.
As you should know already, we prefer to present 24 images every second to make sure the job is done properly but 25 fps is used for PAL TV and 30 fps used for the American NTSC TV format.   These two TV frame rates are a left over from when it was important to conform to electricity supply phasing.
A lot of traditional cell animation is shot "on twos".   That means that each drawing is doubled up,
or shot twice so when the animation is run back at 24 fps it effectively only presents 12 drawings per second.  That is a lot easier than drawing 24 pictures for every second but then this problem is irrelevant for computer animators because our keys and key poses are automatically interpolated.
We will discuse other ways of taking advantage of the human eye later on.

"Persistence of Vision" is relevant when film is projected in the cinema.   The film projector, in order to "pull down" the next frame of film, has to shut down the light source while the film is moved on to the next frame (pulled down).   Depending on the "pull down" rate of the projector, you would be sitting in the dark for a third to half the time of the film's duration. It is the persistence of vision that makes you think that the projection of each image is constant with no interruption.   TVs and computers do not have a "pull down" time.

Maya Graph Editor.

As well as the general Maya environment, you need to familiarize yourself with the Maya Graph Editor because this window allows you adjust the position in time and value of keys and add or delete them.   This window also allows you to change the tangential properties of the keys which in some cases is crucial.   The scrolling and proper manipulation of the time line at the bottom of the Maya environment will also speed up your production.   You will be seeing a lot of the Graph Editor in these tutorials.

How to set Keys in Maya and use the Animation Curves.
The definition of setting a key is committing a value to a particular channel (parameter) at a certain position along the time line.   Usually when setting a key, it is set across more than one channel, each with varying values but set at a common point on the time line.   The most common channels (parameters) to be keyed are the positions, orientation and scale, of Maya geometry, otherwise known as transformation channels.   Everything in Maya, however, can be keyed which yields enormous potential.   Once at least two keys have been defined within a channel then an animation curve is automatically generated which graphically connects the keys together and indicates the interpolation between keys.  The shape of this animation curve, and therefore the motion generated, is dependent on the value and position along the time line of each key, these keys also have additional properties which you will need to manipulate.   (You also need to be aware of the additional properties of the animation curves.)   For the animator, using the geometry windows, setting keys using the "Channel Box", correctly manipulating the "Time Line" and working within the "Graph Editor" on shaping the animation curves, are your main activities within the Maya application.

Try not to "Key All" but only key "Selected" channels.   Selected channels are the ones that you are currently using.   For instance, if you are not animating the values of scale or visibility then do not key them.  Your Graph Editor can get very cluttered if you "Key All".   Channels that need keying are selected from the Channel Box by high-lighting (clicking mouse left) on the channel description. You can use the Shift key to collect adjacent channels or use to the Control key to collect any combinatioin.   Once one or more channels are high-lighted then by holding down mouse right, you can select "Key selected".
You may also set keys by selecting a channel and pressing "s", providing this has been correctly set up.
To set up this provision then see below:-

Select the Animation section.
Select Main Menu Bar / Animate / Set Key (Option Box)
Set Keys on = All Keyable Attributes
Set Keys at = Current Time
Hierarchy = Selected
Channels = from Channel Box

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