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Camera Basics Establishing Focus The one thing that enables the photographer to convey his photographic intent to the viewer is establishing the focus What are the secrets to establishing the best foc.
Camera Basics Establishing Focus The one thing that enables the photographer to convey his photographic intent to the viewer is establishing the focus What are the secrets to establishing the best focus? Let’s find out more about the special features of autofocus (AF) and manual focus (MF) There are two ways of establishing focus: Using the camera autofocus system, or manual selection and adjustment Points-to-note - “AF” refers to “autofocus” This is when the camera tunes itself to establish the best focus when taking a photo - “MF” refers to “manual focus” This is when the photographer adjusts the focus manually to establish the focus Establishing focus is a basic skill in photo taking There are two ways to establish focus The first is through autofocus (AF) operation, where the camera automatically establishes focus The second is through manual focus (MF) operation, where the photographer adjusts the focus by hand In most shooting scenes, AF can a good job of establishing focus When shooting photos in AF mode, all it takes is to simply press the shutter button lightly (“half-press” the shutter button) to activate the AF and AE functions,and the camera takes care of the rest Once focus has been established, press the shutter button down (“full-press” the shutter button) This is what AF is all about—shooting good pictures with very simple operations For more control over the composition of your photos, you can pre -select the active AF area (or AF point) during autofocus operations But AF is not perfect and there is a limit to what it can Sometimes, the subject or the scene makes it difficult or even impossible to establish focus W hen up against these situations, make good use of MF By looking through the viewfinder and turning the focusing ring with our hands, we can establish the focus just as well too Since we can enlarge the focus area when in Live View mode, it is possible to establish focus more precisely AF EOS 80D/ EF-S18-135mm f/3.5-5.6 IS USM/ FL: 124mm (198mm equivalent)/ Aperture-priority AE (f/5.6, 1/200 sec, EV -0.3)/ ISO 3200/ W B: Auto Benefits: Can establish focus quickly Drawbacks: Some subjects and scenes are not ideal for establishing focus Since AF establishes focus quickly, it is very convenient in most situations But sometimes there are subjects or scenes that are not ideal for establishing focus It is wise to switch to MF when the situation calls for it MF EOS 6D/ EF50mm f/1.8 STM/ FL: 50mm/ Aperture-priority AE (f/3.5, 1/40 sec, EV0.7)/ ISO 100/ W B: Auto Benefits: Can observe the subject with our own eyes as we establish focus Drawbacks: Takes more time before we can actually shoot As we can observe the subject while we adjust the focu s in MF, it makes it possible to establish a more precise focus Nevertheless, the whole process takes more time W e have to spend time establishing focus before we can go into the actual shooting When the subject or the scene is not right for AF, switch to MF When the subject happens to be in a very dark place, when it is a low contrast scene or when it is a scene where the subject is sometimes blocked by nearer objects (such as when photographing animals in a cage), AF cannot establish focus easily W hen faced with these situations, switch the focus switch on your lens from AF to MF By switching to MF, we can establish focus by adjusting the focusing ring by hand Related concept 1: AF Lock Know the “AF Lock” shooting technique, this is a way o f taking photos in AF mode where the focus is first established before fine -tuning the composition of the photo First, manually select the active AF point Choose the AF area/point that is located closest to the subject of interest in your ideal compositi on Although AF Lock can be applied with any AF area mode, in general, the centre AF point should have the highest precision and is the best choice when dealing with dark scenes Next, align the selected AF point with any part of your intended subject, and press the shutter halfway When the camera has established focus, leave the button half pressed and fine tune the composition When that is done, press down fully and complete the shoot If you can master the technique of AF Lock, you can place the primar y subject (that you established focus on) anywhere within the image frame —not just in the centre Selecting the active AF points (*on the EOS 760D) Press the AF point selection button (circled in red) to display the screen for Single-point AF (Manual selection) *If another mode is displayed, change the mode using the AF area selection button The Single-point AF (Manual selection) screen allows you to choose the active AF point Next, use the Main Dial, the Quick Control Dial or the touchscree n to select your preferred AF point Here, the point to the left of the centre AF point is selected Related concept 2: The back-button AF technique Normally, when the shutter button is half pressed, AF (focus establishment) and AE (exposure determination) are activated simultaneously But by customizing the camera, we can get AF and AE to operate independently You this by operating the AF with the AF-ON button in the back of the camera (or the AE lock button), and the AE with the shutter button W e cal l this technique the back-button AF technique The advantage of this technique is that when the camera is in AF Lock mode, there is no need to keep the shutter button half pressed Once focus is established with the AF-On button, the point of focus is fixe d, and won’t change even when you remove your finger from the button With this technique, you can take as many photos as you like with different scenes but the same composition The back-button AF technique You can customize your camera to carry out f ocus establishment and exposure determination independently of each other 1 Establish focus in AF-ON mode Press the shutter button to release the shutter Use the AF-ON button (or AE Lock button) to establish the focus, then release the shutter with the shutter button W hen you want to reestablish the focus, all you have to is to press AF-ON again EOS 5D Mark III/ EF24-70mm f/2.8L II USM/ FL: 70mm/ Aperture-priority AE (f/2.8, 1/400 sec, EV+0.6)/ ISO 100/ W B: Daylight I established focus on a cat that appeared all of a sudden with the back -button AF technique, engaged AF Lock and then fine -tuned the scene I managed to try out different compositions continuously with the help of the technique ... to “manual focus? ?? This is when the photographer adjusts the focus manually to establish the focus Establishing focus is a basic skill in photo taking There are two ways to establish focus The... establishing focus: Using the camera autofocus system, or manual selection and adjustment Points-to-note - “AF” refers to “autofocus” This is when the camera tunes itself to establish the best focus. .. first is through autofocus (AF) operation, where the camera automatically establishes focus The second is through manual focus (MF) operation, where the photographer adjusts the focus by hand In