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Camera Modes (part 2) - The Creative Zone
We touched on scene modes in an earlier section however now that you have a fuller understanding of exposure, apertures, shutter speeds etc. we can look at some of the more creative modes your camera has to offer. Bear in mind the way some of these modes work on various cameras may differ slightly.
Full Auto Mode and Programmed AE (P)
If you have a point-and-shoot camera this is probably the only mode it has (except for some scene modes). The camera makes ALL the decisions regarding the exposure (ie. it will set the aperture, shutter speed and sometimes the ISO as well, although on certain cameras, ISO is set to auto or manual using a separate menu option).
Some cameras will have an auto mode AND a programmed AE (‘P’) mode - the differences between them vary between different cameras. Usually the ‘P’ mode will enable extra options that aren’t available in the full auto mode (such as exposure compensation, manual ISO, etc.) to give the photographer a little more control while guaranteeing a reasonably accurate exposure.
Another feature that some cameras have in ‘P’ mode is the ability to select different combinations of aperture and shutter speed while retaining the correct exposure level, usually by rotating the command dial - a feature called program shift. This gives you some flexibility to control the depth-of-field from within the ‘P’ mode without having to switch to Aperture Priority mode.
Aperture Priority (A or Av)
Available on some of the better compact cameras and all DSLRs, this is considered a semi-automatic mode. The photographer selects the aperture required (usually to control the depth-of-field) and the camera will select an appropriate shutter speed to ensure the ‘correct’ exposure. As most cameras have a large possible range of shutter speeds (30s to 1/4000th on many DSLRs covers 17 EV) the camera is usually able to pick an appropriate speed however, under certain circumstances, it may not be possible (for example if you select a large aperture on a very sunny day or a small aperture in low light). If this is the case, the camera will indicate possible over or under exposure by having the shutter speed indicator flashing in the viewfinder or on the screen. If this is the case either select a different aperture or change the ISO setting.
If exposure compensation is used, the camera will adjust the shutter speed - a positive exposure compensation will give a slower shutter speed and a negative compensation will give a faster shutter speed.
Shutter Priority (S or Tv)
Like the aperture priority mode this is available on the more advanced point-and-shoot cameras and all DSLRs. It works in a similar way to the aperture priority mode except that the photographer sets the shutter speed and the camera selects the aperture. As the range of possible apertures the camera has to select from is usually a lot less than the range of shutter speeds (especially on compact cameras), there is a greater chance of the photographer picking a shutter speed for which the camera is unable to select an aperture. Therefore it is not a mode that we would normally use.
The argument in favour of shutter priority mode is that, when shooting sports photography you can select a high speed shutter to freeze the action. We would argue that this is even easier in aperture priority mode as you just open up the aperture to its widest (lowest f number) and the camera will select the highest shutter speed it can to ensure correct exposure.
Exposure compensation can also be used - a positive EC value will give wider aperture (lower f number) and a negative EC will give a smaller aperture.
Manual (M)
I am sure you can probably guess what this mode is for. The photographer is able to select both the aperture and the shutter speed, thereby having complete control over the exposure. The camera does not set anything that affects the exposure, therefore exposure compensation has no effect in manual mode. Of course if you want to increase the exposure by one stop, you just select a slower shutter speed or a bigger aperture. Unlike the other modes mentioned in this section, the camera won’t compensate for a change made by the photographer by altering something else.
A useful feature of nearly all cameras is that the exposure meter still functions in an advisory capacity. It will usually represent as a pointer on a bar in the viewfinder or on screen whether the shutter speed/aperture that you have selected will over or under expose the image when compared to its own readings, and by how much.
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In the illustration on the right (from a Fuji S9600 camera) the exposure bar is showing the image to be very slightly overexposed (based on the camera's guess of what the ideal exposure is) as the white dot is slightly nearer the ‘+’ sign. Changing the aperture from f/4 to f/4.5 or f/5 would probably bring this back to centre.
Although it is tempting to always use one of the auto or semi automatic modes, it is worthwhile spending some time shooting in manual mode and getting a feel for apertures and shutter speeds. It really doesn't take that long for it all to become second nature. |
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