P/S/A/M resp. P/Tv/Av/M, the advanced camera modes are decoded here. Read here how they differ and how to find your favourite mode.
The exposure metering gives the input for exposure control. Measuring the brightness of the subject plus/minus a possible exposure compensation provides the brightness of the subject and then it is time to select a matching combination of aperture, exposure time and ISO.
The question you have to clarify with your camera beforehand is: who takes care of what? It's your decision and you tell your camera in two parts:
This type of operation has survived from the pre-digital area of photography until today. In analogue photography, the ISO sensitivity was fixed with the film inside the camera, only aperture and exposure time could be adjusted from shot to shot. The power of habit seems to play a big role; I have only come across two camera types that go a different way, more on that below.
P, S, A, M resp. P, Tv, Av, M with Canon are the camera modes for actively participating in exposure control. The modes with self-selected favourite settings are also belong to this group if you have assigned them P, S/Tv, A/Av or M.
Smartphones do not have these modes, but Samsung and Huawei, for example, have a "PRO" mode in which you can set exposure time and ISO. The aperture is unchangeable.
Here is the work allocation for these four modes:
|P||leave or shift camera proposal||aperture and exposure time|
|S / Tv||exposure time||aperture|
|A / Av||aperture||exposure time|
|M||aperture and exposure time||--|
The camera suggests a combination of aperture and exposure time. This is convenient, your camera will take care to avoid shutter speeds where there is a risk of camera shake and can also keep an eye on the focal length to decide.
Unlike in full automatic, however, you can change the selected combination. This is called programme shift. The pictures show an example of a corresponding camera display.
The common operation seems to be
I have come across the following variants with compact cameras:
If this does not work for your camera, please refer to your manual.
The programme shift hits limits at the camera's largest and smallest aperture, so if it doesn't react, that may be the cause. And with flash photography, your camera will select a fixed exposure time of usually 1 ⁄ 60 s and then also ignore your attempt to shift the programme.
You set an exposure time, the camera chooses a suitable aperture.
The designation as S comes from shutter, Canon's Tv stands for "time value". Sometimes the mode is also called aperture priority, which is the same thing.
How to use it:
You set an aperture, the camera chooses a suitable exposure time.
The designation A comes from the aperture, Canon's Av stands for "aperture value".
You set an aperture and an exposure time.
Your camera may have an indicator to help you determine whether and how far the resulting exposure deviates from the automatically measured one. However, it does not intervene in the aperture and exposure time. You are responsible for the exposure yourself... at least most of the time. Because there are two situations in which manual control is also a kind of automatic:
If you are interested, please try it out on your camera, there may be differences depending on the manufacturer and model. It works for Nikon.
To operate the manual mode:
To set a fixed ISO sensitivity, you will probably find a button labelled ISO on your camera and then be able to set a value with a dial or arrow keys.
Otherwise you will need to go into the camera menus, again I have included sample photos and hope they are enough to help you find the right way on your camera.
ISO automatic means that the camera automatically changes the ISO sensitivity instantly when needed. ”When needed“ means if it is necessary to achieve desired apertures and exposure times.
The logic behind automatic ISO is:
Slight deviations and additional subtleties are of course possible depending on the manufacturer and camera model.
The ISO automatic is wonderful for quick, spontaneous photography when you want to prevent camera shake caused by long exposure times. On the other hand, it can drive up your ISO sensitivity if you are shooting in the dark with a tripod and forget to turn it off.
With the enormous choice of camera models, there may be more that operate differently, but here are two I have come across so far:
Fv is a clever, contemporary variant of Canon, ”flexible automatic“:
Fujifilm's system cameras have their own operating concept, which has a similarity to Canon's Fv mode:
As a result the camera behaves as if it were in a P, S, A or M mode. It shows these symbols on a camera, but actually you don't need to know them at all, just look at the camera body to see which of the three settings is put to automatic.
This is Fujifilm's own very nice clear operating concept that sets it apart from other manufacturers.
Programmed auto P is convenient and fast. If you are taking snapshots and the exact exposure time and depth of field are not so important for your shooting situation, it is perfectly adequate. Together with ISO automatic, it is as flexible as full automatic, allows you to be quick, not to miss a shooting moment. That is my preferred choice for snapshots or at events where I photograph people.
Aperture priority A/Av is my second choice, because the active selection of an aperture for the depth of field matters more often than the preselection of a certain exposure time. It is also often recommended in photography courses to use this mode to get into the habit of consciously setting an aperture.
Shutter priority S/Tv is for those situations where you really want to have a certain exposure time for a suitable amount of motion blur. This can be annoying with programme automatic and programme shift, because it can happen that with a slight camera swing the subject brightness changes and then the exposure time jumps up and down.
I rarely use the manual mode M. The reasons for it can be: