blacknet
Contributor
This is a question thats raised quite often and I thought I would help clear the air on what modes your camera has, how they work and what they mean.
Cameras have several modes that are creative tools and include: Auto, Manual, Aperture priority and Shutter Priority. Many cameras have macros that differ according to the make/model and I wont go into those here as there are too many.
Before I go into details on each mode let me take the time to explain some basic terms.
F/stop
This simply means how much light is allowed to enter the camera. Think of it as a cattle gate. The f/stop is how wide the gate is. In photography it is a diameter measurement of the iris in the lens. This is called the aperture and it works just like the iris of the human eye. The more light you have the smaller the opening, the less light the larger the opening. F/stop is expressed as F/2.8, F/4, F5.6, F8, F16, F32 and so forth.
Shutter speed
This is how fast the film is exposed to the available light coming into the camera. It is a time value. Think of this as how long the cattle gate is opened. Shutter speed is expressed as 1/8, 1/15, 1/30, 1/60, 1/90, 1/125, 1/250, 1/500 and so forth. The longer the time the more moving objects tend to blur. The shorter the time the more moving object are frozen. Take a water fall for example. If you use 1/8 the water will be smooth and flowing, each drop will be blurred giving it that flowing effect. If you use 1/500 you will see each individual drop of the spray as it is frozen in time.
Focal length
This is the length of the camera lens. The longer the length the more narrow the field of view is. A 1000mm lens will see 2.5 degrees while a 17mm will see 104 degrees.
Depth of field
This is how much is in focus. I will not get into the circle of confusion as its beyond the scope of this article, but it plays a big part. Basically the depth of field is the range of distance where an object is sharpest.
Film Speed
This is how sensitive the film is to light. The bigger the number the more grain you see. At 3,200 ISO the image will look like sand art, at 50 ISO you will not see gain.
Hyperfocal Distance
This is the distance scale that will give the broadest depth of field. Using the hyperfocal distance will allow you to have most things in focus at any given time and one less control you have to worry about.
Now we can dive into the individual modes.
Manual mode:
This is where you have total control over F/stop, shutter speed and aperture size. You can vary the exposure any way you see fit.
Aperture Priority Mode:
This mode allows you to set the aperture or f/stop of the lens and the camera will automatically set the shutter speed. If you have something like a Nikonos or Sea & Sea motor marine II then this is your primary mode as this is an all manual camera. This mode is great for macro work as you have full control over the depth of field, remember the smaller the opening the greater the depth of field and the more light you need.
Shutter Priority Mode:
This mode allows you to set the shutter of the camera and the camera will automatically set the aperture of the lens. This is usually for more advanced cameras than the nikonos or Sea & Sea motor marine II. If your action is fast paced like dolphins then this mode is for you.
Auto magic Mode:
In this mode the camera will set everything for you. From the definitions above you can see that in low light the camera may choose a longer shutter speed thus making moving object blurry.
As usual I dont expect everyone to fully understand things that I wrote. If you have any questions or comments then please either post them or contact me about them. Remember there are no stupid questions!
Ed
Cameras have several modes that are creative tools and include: Auto, Manual, Aperture priority and Shutter Priority. Many cameras have macros that differ according to the make/model and I wont go into those here as there are too many.
Before I go into details on each mode let me take the time to explain some basic terms.
F/stop
This simply means how much light is allowed to enter the camera. Think of it as a cattle gate. The f/stop is how wide the gate is. In photography it is a diameter measurement of the iris in the lens. This is called the aperture and it works just like the iris of the human eye. The more light you have the smaller the opening, the less light the larger the opening. F/stop is expressed as F/2.8, F/4, F5.6, F8, F16, F32 and so forth.
Shutter speed
This is how fast the film is exposed to the available light coming into the camera. It is a time value. Think of this as how long the cattle gate is opened. Shutter speed is expressed as 1/8, 1/15, 1/30, 1/60, 1/90, 1/125, 1/250, 1/500 and so forth. The longer the time the more moving objects tend to blur. The shorter the time the more moving object are frozen. Take a water fall for example. If you use 1/8 the water will be smooth and flowing, each drop will be blurred giving it that flowing effect. If you use 1/500 you will see each individual drop of the spray as it is frozen in time.
Focal length
This is the length of the camera lens. The longer the length the more narrow the field of view is. A 1000mm lens will see 2.5 degrees while a 17mm will see 104 degrees.
Depth of field
This is how much is in focus. I will not get into the circle of confusion as its beyond the scope of this article, but it plays a big part. Basically the depth of field is the range of distance where an object is sharpest.
Film Speed
This is how sensitive the film is to light. The bigger the number the more grain you see. At 3,200 ISO the image will look like sand art, at 50 ISO you will not see gain.
Hyperfocal Distance
This is the distance scale that will give the broadest depth of field. Using the hyperfocal distance will allow you to have most things in focus at any given time and one less control you have to worry about.
Now we can dive into the individual modes.
Manual mode:
This is where you have total control over F/stop, shutter speed and aperture size. You can vary the exposure any way you see fit.
Aperture Priority Mode:
This mode allows you to set the aperture or f/stop of the lens and the camera will automatically set the shutter speed. If you have something like a Nikonos or Sea & Sea motor marine II then this is your primary mode as this is an all manual camera. This mode is great for macro work as you have full control over the depth of field, remember the smaller the opening the greater the depth of field and the more light you need.
Shutter Priority Mode:
This mode allows you to set the shutter of the camera and the camera will automatically set the aperture of the lens. This is usually for more advanced cameras than the nikonos or Sea & Sea motor marine II. If your action is fast paced like dolphins then this mode is for you.
Auto magic Mode:
In this mode the camera will set everything for you. From the definitions above you can see that in low light the camera may choose a longer shutter speed thus making moving object blurry.
As usual I dont expect everyone to fully understand things that I wrote. If you have any questions or comments then please either post them or contact me about them. Remember there are no stupid questions!
Ed
