Coming back from my photographing days at the end of the 80, the digital world now seems extraordinary. The gears, the quality of the sensors and lenses, the easy workflow to get a proper exposure and an instant image, are wonderful for the popularity and overall quality of images. Now, following the ordinary use case of making photographs, I found myself in the decision of what camera or shooting mode to use: the alleged pro’s Manual mode (M), the Aperture Priority (AP or Av), the Shutter Priority (SP or Tv) or the almost infamous Program mode (P).
The spectrum of favorable arguments came from the Program mode enthusiasts (street and occasionally snapshot photographers) to the strict dictate of Manual modes, if you want to be considered a «real» professional. But, what are the concrete aspects, the use cases for every photo opportunity? After all, almost all photographers use the light metering mechanism (the light meter) of the camera to get the proper exposure or as a baseline. That said, the decision tends in favor of creative options: should you want great depth of field (DoF) or do you need to stop motion? Or on the contrary, you want to show motion in a still backdrop? Do you need to be ready to shoot without thinking, in the street or in an action event? Or it is a controlled studio your scenario? Let’s see the typical cases and why you should prefer one mode over the others.
Other important variables here are the ISO value settings and the light sources. Should you set the ISO manually or turn on the Auto ISO? How to get the lowest ISO in any selected mode, auto or manual? The well-known exposure triangle explanations (aperture, shutter speed, and ISO) omit occasionally the light source as another variable you can alter in some situations (more obvious in the studio environment, but also in outdoors during daylight, by moving your subject out or under the sun light).
Let’s begin our analysis with:
The Manual Mode
The Manual mode gives you all the control and the responsibility of the exposure. At least this is the main argument by all its enthusiasts. But what is the difference between this mode and any of the semi-auto modes (A or S), if your guide is always the automatic light meter system of the camera? If the camera says that you are overexposed or underexposed with your settings, you reasonably would increase or decrease any of the values (Aperture, Shutter speed, or ISO) to get the proper exposure. But by doing it—and this is exactly the value of this mode—you have all the power to choose. If you want to increase the depth of field (DoF), then you select a higher Aperture number. If you want to freeze movement, then you increase the Shutter speed. If you want to avoid noisy images, you decrease the ISO number. This is the main reason the Manual mode is the mode for the studio, that long pace, creative workflow, when you could seat there in front of your subject to think about the effects, and consequences, of your selections. After many years of shooting, you will choose almost immediately your settings without too much adjustments from the light meter reading. For the novice, there are plenty of information and guidelines out there to pre-select settings under several typical scenarios (sunlight, indoors, action, etc.).
But again there is the question, if you will want control over any of the exposure values to get an especial effect, why you don’t choose the one you want to settle in a manual mode, letting all the others in auto (auto ISO, manual Aperture, auto Shutter speed, e.g.)? That’s the relevance of the other semi-auto modes Aperture and Shutter priorities.
Manual Mode is the perfect choice por portraits and still life in the pace of the studio. Also, it is perfect for landscapes or architecture photos. But is it that good for action (sports, street photography, wildlife, e.g.)? These scenarios require quick decisions and adjustments, and sometimes lots of shots within the proper exposure. Unless you first select a fast shutter speed (1/500th or higher), the Manual Mode doesn’t fit for action. You can’t expect anybody to configure settings from 1/60th to 1/1000th on the fly, and open at the same time the aperture or change the ISO to compensate the loss of light. So, the choices are obvious. Or you start with the higher shutter speed in M, risking the opportunity of a shot while configuring your aperture and ISO, or select the Shutter priority mode for the same purpose, but all the other variables in auto.
Conclusion: use Manual mode when you have plenty of time to configure your shots, or when you can presets settings clearly for common unchanging scenarios. In any case the Auto ISO is highly recommendable (with an ISO max value and minimum speed threshold when available).
In a another post, I will treat the Aperture and Shutter Priority Modes.