FOCUS
by Diane Bohlen
There is nothing worse than checking your photos on the computer to find many of them are not in sharp focus. Here are some reasons for getting blurry photos:
Camera Blur
Pressing the shutter button too hard or too excitedly can cause blur. It causes the camera to move while the shot is being taken.
If the shutter speed is slow to let in more light it can cause camera shake because we all shake a little bit. In general, to take a hand held shot the shutter speed needs to be the same or faster than the focal length. e.g. 60mm focal length needs at least 1/60th of a second speed. Also increase the ISO to let in more light. Otherwise use a tripod.
Motion Blur
When the shutter speed is too slow to freeze the action of a moving subject you get motion blur. Increase the shutter speed. Sports needs 1/1000th , walking needs 320th and portraits need 1/100th. Also increase ISO. Use AI Servo focus mode and AF point expansion or AF Zone points (explained later) Use continuous mode where the camera takes multiple shots, one should be good.
Too Narrow Depth of Field
Often photographers like to create a creamy. Blurry, or bokeh background especially for portraits, birds and close ups. But if you go too far and the DOF is too narrow you will not get the whole subject in focus. It may just be the eyes. By the way you should nearly always focus on the eyes of people and animals. That is where the viewer looks first.
If you use f2.8, a long lens and stand close to the subject you will get a very narrow DOF. Decrease (bigger number) the aperture until all the face is in focus.
In group photos some people will be out of focus if the DOF is too narrow or the people are not on the same plane. Focus on the nearest person and decrease aperture until all are in focus. Check in the LCD screen.
For Landscapes, where you want everything to be as sharp as possible, use a small aperture (big number). Then find the Hyperfocal Distance, it can be worked out with a mathematical equation or with a phone app. But a general rule is to focus one third of the way up from the bottom.
It could be the lens
Not all lenses are equal. The lens can make a difference. Entry level cameras have cheaper lenses. However, you can still get very sharp photos. Don’t use the extreme aperture settings at either end of the scale. Don’t use extreme focal lengths at either end of the range like 18 to 55 use somewhere in the middle. Lenses have a “sweet spot” where the photos are the sharpest try to find it on your lens.
Fixed lenses are supposed to create the sharpest pictures. A prime lens is a fixed lens. They are usually 55mm focal length.
Buy the best lens you can afford. Be careful they are not all interchangeable with all cameras.
Diopter not properly adjusted
There is a very small wheel next to the viewfinder. It adjusts the viewfinder to match your eyesight. Turn the wheel until everything looks sharp. This doesn’t alter the photo but lets you see what should be sharp.
Improper Focus
This is probably the most complicated part of getting the photo crystal clear. It is understanding how auto focus works in your camera. There are different focal points and focal modes. You need to investigate your manual and menu to find out how to use these points and modes.
Here I will explain Canon, Nikon and Sony HX60V.
When you look through the viewfinder you see a bunch of dots or squares those are the focal points to show you where the camera is focusing. The point usually blinks red or green when the camera sets the focus.
In Autofocus Automatic (AF-A) the camera analyzes the scene and determines which AF points to use. Based on whether the subject is moving or stationary, it automatically switches between AF-S and AF-C to achieve focus.
Automatic Focus Modes
AF-S Single Servo AF (Nikon)/ One-Shot AF Canon/AF-S Sony
The single AF mode locks focus on the subject as long as the shutter button remains partially depressed. The focus point will be illuminated. Once the focus is locked keep your finger on the button half way depressed then you can recompose the photo before depressing the shutter all the way down.
AF-C Continuous Servo AF Nikon/ AI Servo AF Canon/ AF-C Sony
The camera continues to focus and adjust focus on the selected focus point until the shutter is activated. This AF Mode is ideal for subjects that are moving.
Automatic Focal Points
Besides the focal modes there are also a range of options to select focal points and areas or zones.
Canon has:
Spot AF, Single Point AF, AF point expansion, Zone AF, 19 point AF
Nikon has:
Single Point, Dynamic Area, Auto, 3D
Sony has:
Wide, Centre, Flexible spot
Spot Focus. This is the best choice for stationary subjects. You can move it to different parts of the scene to focus where you want it. Alternatively you can lock it and recompose.
Single point is similar except it covers a bigger area.
AF Point expansion is where you can select a primary point accompanied by a number of surrounding points for subjects that are moving or that don’t offer enough contrast for a quick focus.
Zone AF or Dynamic Area is where there is a cluster of points that can be moved around the scene. If the subject moves the camera can use another point to refocus. It is best for moving subjects.
3D and 19 point AF is where all focus points are active and track focus.
Your camera always focuses on one specific spot in the scene. Even if you activate multiple focus points the camera will choose the best of both worlds and compromise between the focus selection and focus in the middle.
Simon Ringsmuth says he prefers spot focusing 99% of the time. It allows him to move around the focus point in the viewfinder. It is great because you have control over where the focus is placed. I never let the camera to take control of focus it’s a recipe for blurry photos.
With fast moving wildlife or sports he uses the centre zone/area focus points because he can’t move a single point focus fast enough.
Cross type focal points
Most interchangeable lens cameras have cross type focal points. That means they look along the vertical and horizontal axes to make sure everything is in sharp focus. To find out which focus points in your camera are cross type you need to consult your manual or go online and search your camera for ‘cross type focus points”.
More Tips
Live View
If you are shooting still subjects you can use live view to help get tack sharp photos. Frame your shot on a steady surface like a tripod then zoom in 100% this gives you an ultra close up at your image you can then use autofocus or manual focus to make sure everything is very sharp.
Focus Peaking on mirrorless cameras.
Focus Peaking is a way for your camera to show you precisely what is tack sharp as you focus the lens. With Focus Peaking enabled, as you turn the focusing ring on your lens you will see a swathe of red or green dots travel across the viewfinder. These spots indicate the parts that are in perfect focus and when you see an outline of dots around the part of your image you want in focus snap the picture. You can use it with both manual and auto focus.
Sharpening the Image
There are two types of sharpening. Capture and Output.both are necessary for crystal clear photos. When importing RAW photos into Lightroom or photoshop these programs apply capture sharpening behind the scenes. Output sharpening is using the sharpening tool in the processing programs. The larger the photo size the more it should be sharpened like those to be printed. For the web not so much sharpening is necessary and be careful not to over sharpen or the photo looks unreal and ugly.
Back Button Focus
Within your camera’s menu you have the ability to assign focus to one of the back buttons. This means that your finger is solely responsible for releasing the shutter and your thumb is now focusing.
Your focus will hold. You can set focus and get the shot simultaneously. It is great for moving subjects.
Focus and recompose with ease. It enables you to focus and recompose easily while your subject stays in focus.
More versatile focusing. Use it with continuous focus mode (AI Servo) The shutter doesn’t try to focus for each shot so you can take a series of shots without refocusing.
When someone or something is moving towards you and the plane is changing keep your thumb on the focus button and shoot. Also use continuous focus mode.(AI Servo)
If all these tips fail you can use manual focus. On DSL cameras just switch to manual and rotate the ring on the lens. On Point and Shoot and Bridging cameras go into the menu and find ‘Manual Focus’.
If this fails too maybe you need your camera checked out.
On a phone camera you can focus on the subject by touching the screen and a box comes up which focuses and meters the light. You can move the box by touching the screen. You can make the shot lighter or darker by sliding the bar with a sun on it up or down.
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