I was sitting in a road side café with a fellow wildlife photographer when she asked me a question.
She was about to purchase a new camera body and wanted to know the difference between the $1,500 model she was looking at and a $4,000 model she was also considering.
After careful consideration I gave her my answer
Speed, the need for speed with little or no cost to image quality.
When dealing with long lenses such as the ones we wildlife photographers commonly use, speed is the critical factor next to image quality.
The rule of thumb for getting a sharp image of a stationary subject with a long lens is accepted as being twice the shutter speed of the length of the lens used.
In other words if your using a 400mil lens, you’re going to need a shutter speed of at least 1/800th of a sec and a steady hand to get a sharp image.
Movement is the great enemy of the wildlife photographer.
There are two hurdles to overcome, two types of movement.
1. The photographer being unable to hold the camera steady.
2. Subject movement, which plays an equally important part.
Birds and animals are seldom still unless sleeping, especially the head.
Get the head in sharp focus you can get away with the other parts being less than perfect, but get the head out of focus and that image is heading for the recycle bin.
What is speed?
In this case speed refers to the amount of time the shutter is opened allowing light to strike the sensor in your camera which records all the visual information that you can see through the viewfinder.
The sensor needs a certain amount of light and information to be recorded or absorbed by the sensor to provide the details that make up our photo and time is the critical factor.
The longer it takes for the sensor to absorbed all the information to make a good exposure the more risk of movement resulting in a blurry image.
Too little light and only the brightest parts of the subject matter will be recorded and the darker parts will be filled with what we call digital noise.
Digital noise replaces detail where the sensor has been unable to gather enough picture information to record the fine details in those darker areas and those details are replaced with dots of grain like sand we call noise.
Colour noise is made up of dots of unnatural colour this indicates insufficient detail recorded by the sensor also.
Expensive camera bodies have more sophisticated light sensitive sensors capable of operating at higher ISO speeds (more sensitivity to light) without introducing too much noise.
There are four components or tools you can adjust in your camera to give you a fastest shutter speed increasing your chances of getting a good sharp image.
We will deal with each component as its own blog post.
1. F. stop or aperture settings
2. Iso speed the degree of sensitivity of the sensor, each higher ISO setting increases the sensitivity of the sensor but there is always a trade off on image quality.
3. Focal length bringing the subject closer to the sensor and seeing more detail
4. Compensation exposure, fine tuning the exposure manually with intuition.
When you show an image to someone the image should be telling a story .
Some times movement helps tell that story.
If the head is in focus you can get away with movement.
this bird was moving to fast for the shutter speed although its still a keeper.
Shoveler Ducks are among our fastest flyers , you need supper fast shutter speeds to freeze the action.
I hit 4,000th of a second on this bunch.
Next time we will look at F. stop or aperture settings.