PHOTOGRAPHY EXPOSED
by John Peters A.R.P.S.
SHUTTER PRIORITY MODE
Lets keep things as simple as possible for now, we will preset the ISO or use AUTO ISO, and we will be letting the camera's fancy electronics work out and set the APERTURE whilst we give priority to the SHUTTER-SPEED and decide on it manualy, thus shutter-priority mode.
Smartphones will be covered under SMARTPHONES and for the slightly more advanced in photography, smartphones by their design, behave a little differently. Aperture and depth-of-field (DOF) differ from that of a normal DSLR and lens or a compact camera come to that. Depth of field appears greater, and selected shutter speeds appear higher when compared to a DSLR.
BEGINNERS / KEEPING THINGS SIMPLE
First of all let me say it's no easy decision to switch from automatic mode to aperture-priority mode, shutter-speed mode or even manual mode and may be one of the biggest decisions you'll face in photography. When would you select shutter-priority mode? You might want to freeze any motion or add motion blur or generate the effect of movement such as when photographing a waterfall and these aspects are more important to your photograph than say depth-of-field (DOF). It's also the option often used by sports photographers when freezing the action is given priority over DOF.
With an effort to try and keep things simple, first, we must look at at how a shutter works in a camera or smartphone. If we simply regard the shutter as a sort of blind that opens then closes briefly letting the light through to the sensor. The shutter controls the amount of light reaching the sensor, exposing or making the photograph. The amount of time this blind remains open e.g. 1/250 or 1/60 of a second and becomes your shutter speed. That's a sufficient enough explanation for the time being.
In our diagram above, the mirror flips out of the way first and this is followed by the shutter which stays open for the length of time you have set on the camera via a dial or a menu or setting in the camera. The shutter acts like a blind, letting the light through to the sensor for as long as it's open. That's a good enough explanation for our needs just now.
I know this page is meant to be about shutter-priority photography but firstly, let's consider auto mode or automatic mode.
Let me say that in no way are you any less of a photographer just because you AUTOMATIC MODE or AUTO MODE. The most important thing is that you enjoy your photography and that you get satisfaction from looking at your own pictures or those of others, irrespective of which mode was used to take them.
AUTOMATIC MODE
Automatic mode is relatively hassle free and quite sophisticated now in phones and cameras and automatic mode will make a reasonable exposure most of the time, getting fooled only by awkward situations. Scene modes on some cameras make correct exposure, DOF and motion blur adjustments, that even do away with much of the logic necessary to produce a properly exposed photograph. Scene modes now even encompase elements of composition too.
So, for beginners or painfree photography, why not just set your camera to AUTO OR AUTOMATIC MODE and let the camera or phone work everything out for you. Perhaps there's an element of snobbery attached to using one of the other modes available instead of automatic mode? So what, if you take a few photos at a less than ideal exposure. It's not a crime and no big deal.
I strongly recommend BRACKETING your shots anyway. One of it's advantages are that it should cover any errors in exposure. By bracketing your exposures, you also have other options open to you such as HDR. You may eventually have enough on your hands with selecting and using a particular type of focus and metering, there's often so much to remember but with skill and practise, basic modes or different options can be used. If you are not sure about bracketing, study your user manual.
Above is picture my ideal camera layout. All the controls are dials on the camera or lens for ease of use not having to take the camera from your eye, there is a vari-angle screen to shoot high or low, and an exposure compensation dial to bracket your shots or adjust the exposure. Everthing you need is readily at-hand and no extra menu's need to be navigated. Ideal.
When freezing the action was more important than DOF, shutter-priority was used with a long tele-lens.
TOP TIP If you think your subject may trick your meter as it's set, don't rush to change settings, just walk closer to your subject, fill the frame and viewfinder, then use the exposure lock option if your camera has one or just note the settings that are recommended for aperture and shutter-speed. These settings could be used later on to take the photograph if you are not using auto mode.
TOP TIP No matter what mode you are in, set your shutter-speed high enough to freeze the action. The old maxim of 1/focal-length of the lens is a good starting point but with Image Stabilisation coming into play on more modern cameras and lenses, that old rule may not hold but it's a safe starting point.
Just as a reminder again, the shutter will open/close as per your setting, or in our example, it will rotate or flip out of the way. Given that we tend to get too technical, we should take into account that:
Modern day sensors are pretty good at limiting noise and with many modern cameras / lenses having in-body-image-stabilisation (IBIS) or some form of image stabilisation, holding a camera/lens steady is easier than before. Hand held photographs are a lot easier now, with less camera shake ruining images.
SHUTTER PRIORITY
For a beginner, I recommend settings as follows:
Set ISO at 800 (UK) to give your camera a bigger range of apertures and shutter-speeds than set at ISO 100 as many people tell you to do, to keep noise (digital) or grain (film) at a minimum. That's a bit OTT for beginners, just set your ISO to 800, 400 or even 100 if a rare bright day occurs but if possible, set it higher than ISO 100 as is normally recommended.
You may want to use this wee guideline when setting your ISO.
Very Sunny - ISO 100, Sunny - ISO 400 or 800, Dull - 1600, probably 400 or 800 ISO is best (UK).
Yes, you may have read about digital noise at high ISO's but who cares unless you are making very large prints or enlarging digital images to a big size. Much better to take a photograph than not take a photograph. Pre-setting your ISO is a smart move.
THE IMPORTANT BIT (IN DETAIL) :
HOW TO SET THE CAMERA TO SHUTTER PRIORITY MODE
Set the camera / lens to 'S' or Tv to make the camera / lens operate in shutter-speed priority mode and effectively let your camera or phone calculate what aperture to use for the exposure, you have given priority to the shutter-speed.
Set 1/250 or even 1/500 second as a shutter-speed and take a photograph. Check the photograph on the back screen of the camera or in the viewfinder if you have to, it should be reasonably exposed. Remember, in digital it costs nothing and if an image needs deleting, it's easy to do. You should have a reasonably exposed photograph.
Using simple rules, we have let the camera decide on an aperture providing a hand-held, shake-free photograph. In other words, you have just used your camera in shutter priority mode.
TOP TIP For more experienced togs, read your user manual to become sufficiently familiar with your equipment in order to be able to operate the main camera/lens functions without removing the camera from your eye. Why, the lighting or conditions may change in a fraction of a second and you don't want to miss the peak moment whilst fumbling with your camera. Bear in mind that someone, or a group of people that know your equipment inside-out, have probably taken weeks to compile your user manual which is probably full of juicy information. Boring I know, but familiarity with your equipment could become important to you further down the line.