Perfect action shots are actually quite hard to obtain. Action shots are of moving subjects and unfortunately most cameras aren't that good at taking photos when the subject is moving. You'll most likely get a blurry image because the subject has moved while the shutter is open. The trick is to freeze the action and remove motion blur, yet still give the illusion of movement.
The movement of every object has it’s own complexities – for instance a helicopter’s rotor or a horse’s legs is quite different to a racing car’s wheel.
With a fast moving subject, you can use a faster shutter speed to achieve a sharp image with no motion blur. One way to do this is use your camera's Shutter Priority mode which gives you the ability to increase shutter speed to at least 1/250 second – but fast moving subjects will require even faster shutter speeds. If you don't have shutter priority mode, decrease the ISO setting (digital camera). This will tend to increase the shutter speed automatically because you have enabled the camera to work with less light (at the expense usually of image quality). Although this will freeze the action, you'll also freeze the illusion of movement, thereby the result will look like the subject is not moving at all. An example is when a stationery photographer tries to take a photo of a vehicle driving past on the road, lines up the shop
and waits for the vehicle to be in the frame and then takes the shot using a very fast shutter speed of say 1/500 sec, or even 1/1000 sec.
A better solution to taking a photo of a moving object that remains in focus, whilst the background is blurred, is to pan the moving object. Panning, means you follow the subject with your camera (ie. move the camera) and only press the shutter when the object reaches the position you wish to take the shot. The background will be blurry as it will have moved relative to the camera during the same time but the subject will remain in focus.
When taking action shots that are not truly fast moving, such as 4WD obstacles, which could be large boulders, steep dunes, or rutted tracks, you want your photography to purvey the extremes angles and give the viewer something to marvel at. An excellent way to depict this in photographs is to get down low and take the photography of the underbody of the vehicle - even better if you use a wide angle lens and move in very close to achieve some distorted perspective and make the closer object appear larger, for instance.
But these tricks all work if you have a simple subject to work with, however what about when your subject is the terrain, ie. a steep hill
climb. Many a traveller's trip snaps just don't do justice to the terrain but you can improve the result by understanding how to use perspective and shadows to depict shape and form.
Shadows:- When shadows are present, they provide an indicator of depth, so an image of a hill climb may look much more dramatic late in the evening (given it is north or south facing) than in the middle of the day.
Perspective:- This allows aspects of the image to be emphasised, and along with this, focal length is an important consideration. Long lenses (long zooms) tend to bring subjects closer together. Wide angle lenses tend to make subjects appear further apart.
Using these to things together, can allow you to choose a viewpoint and focal length to emphasise the aspects of the subject that are important.
Rocks:- Any rocks close to the camera (you might have to lie on the track) will look massive and the 4WD in the background at the top of the frame perhaps, will look comparatively small compared to the terrain it is crossing if you are using a wide angle lens.
Vertical Trees:- Trees in the background can also add emphasis to the angle of approach of the vehicle when there is some visibility of the side of the vehicle. This is not so apparent when the vehicle is being shot head-on.
The skilled photographer will purposefully chose a viewpoint and shooting angle for a photograph depicting a steep hill
climb to best capture size and dimension, rather than flatten it out which may render the hill
to appear as if a straight flat road leading ahead. Obviously composition plays a large part too and using a digital camera you'll be able to experiment by trial and error until you get just the right result.