This means that accurate focusing is much more important at shorter focus distances. So lenses are built to have greater travel in their focusing range close-up, to allow the lens to focus more accurately in the range where precise focus is needed. Not all lenses feature focusing scales, but all lenses do have greater travel in their focusing range at close focus than they do near infinity.
If your lens does feature a focusing scale, it can be useful. The main type of photography where it comes into use is for street photography. You can set your camera or the lens to manual focus mode. Then using the focusing scale, set the lens to focus at a certain distance that you want to photograph your subjects from, e.
Fixed focal length lenses i. This indicates how large the depth of field will be at a given aperture. Using this you can work out how much of the image will be in focus. If your lens has a focusing scale but no depth of field markings or the markings aren't very helpful , then you can use a depth of field calculator to work out the depth of field.
When you know the depth of field that you will get at your selected focus distance and aperture, it means that you know the acceptable distance range a subject must be in for them to appear in focus. The calculator tells me that this means that anything between 2. So if I use the lens with those settings for street photography, I just need to try and make sure my subject is somewhere between 2.
The benefit of this 'fixed focus' way of shooting is that when you see an interesting shot, you don't have to focus on the subject. So long as they are within the range of acceptable focus, you can just snap a shot straight away. Ya Dig!!! You don't even have to look through the viewfinder or at the camera's LCD, so you can shoot from the hip. Shooting from the hip is sometimes preferred as it makes you more inconspicuous.
Your presence is less likely to disturb people's natural actions and expressions than if they see someone with a camera up to their eye taking a photo of them. I should point out that the majority of street photography is not done using fixed focus shooting. But it is a handy technique to have in your arsenal. Another instance where fixed focus is sometimes used, is in landscape photography.
Here a technique called hyperfocal focusing is used. The idea is to get as much into focus as possible, from quite close to the camera, all the way into the distance infinity.
The distance that the camera should be focused at to achieve this is known as the hyperfocal distance. It is dependent on the aperture that you will be shooting at. The smaller the aperture, the more will be in focus, and the nearer the camera you can focus. For calculating the hyperfocal distance, there is a nice calculator and tutorial on the Cambridge in Colour website: Hyperfocal Distance.
I would like to stress that most landscape photography is not done using this fixed focus technique, but it can be useful in some situations. Personally I find focusing using an optical viewfinder very difficult for anything other than macro photography. But there are plenty of people who don't have any problems focusing manually using an optical viewfinder. If, on the other hand, you have a camera with no linkage between the lens and the viewfinder, then you cannot see any changes in focus you make so manual focus using the viewfinder would not be possible.
For example, this is the case with the optical viewfinder accessories available for some mirrorless cameras. Cherry blossom in central NJ by Dr. Focusing using an optical viewfinder is quite simple, just turn the focusing ring until the image looks in focus in the viewfinder. Normally you will probably want to turn the focus ring so the image looks in focus, then keep turning until it just starts to go out of focus. Turn the focus back the other way just a little to where the focus was sharpest, and you should be back at the correct focus distance.
The ease of manual focusing using an optical viewfinder depends quite a bit on your camera model. Lower end DSLRs often have small and relatively dark viewfinders that can make manual focusing difficult. High end full frame cameras have much larger and brighter viewfinders, which make it easier to focus manually. The focusing screen used in the camera is another thing that affects how easy it is to get accurate manual focus.
Some DSLRs have interchangeable focusing screens, with a range of screens available. Super precision Matte screens and split prism focusing screens can both make manual focusing easier than the standard focusing screens. Usually it is a case of using a small tool to pop out the old focusing screen from the camera, and then snapping the replacement screen into place. Other DSLRs don't officially have interchangeable focusing screens, but a range of third party companies manufacture and offer installation of screens suitable for manual focusing.
The disadvantage here is that you can't easily switch back to a normal focusing screen. There are a couple of disadvantages of split prism and super matte focusing screens though. In some cases more often with third party split prism screens , they can also throw the camera's metering system off, so you can't rely on auto exposure so much. Overall, the main way to get better with manual focusing when using an optical viewfinder is practice, practice, practice.
Other than older DSLRs that don't have a liveview function, this method of manual focusing is available on most cameras that allow manual focusing. Personally I find this method easier to focus accurately with than using the optical viewfinder. Focus the lens so that the image looks in focus. Now zoom in on the area where you want the critical focus to be.
At maximum zoom you should be able to make sure that you get the focus spot on where you want it. Then take the picture! Some cameras also have a feature known as focus peaking.
The exact way this works differs between camera manufacturers, but generally a colored outline is shown around anything within the plane of sharp of focus. This makes it quick and easy to see where the focus in the image is. For more information on how focus peaking works, see this article on the Luminous Landscape website: How 'Focus Peaking' works. You can see an example of focusing peaking in action on a Sony NEX camera in the video below:.
Different camera manufacturers implement their liveview systems slightly differently. Some show the live sensor feed with the aperture of the lens set to wide open. This means that you don't get an accurate preview of the depth of field, but does allow you to easily place the plane of critical focus in the image where you want it.
To see what the depth of field will be like, you can press the depth of field preview button on the camera. This will temporarily stop the lens down to whatever aperture you have set for shooting at.
These distance windows can be helpful when all else fails, giving you a chance to judge or even measure the length. The distance the camera provides should be in both metric and imperial measurements. Most lenses should have a focus distance window or even numbers engraved on older lenses. But they are getting less common, especially in mirrorless ranges of cameras.
This window is an active lens element that moves according to how much you alter the focus ring. This method is not the most accurate way of focusing an image.
But it can be a lifesaver when emergency occasions arise! The rangefinder presents a section showing two images of the same scene. To get the desired focus point, you have to overlay the two images to match them up perfectly. These may be due to personal preferences or from the automatic features of your camera not allowing you to be fully in control. A pretty obvious one, but regardless, manual focusing allows you to pick the exact subject you want to focus on.
It is handy when there are many layers throughout your scene. In a dark environment, you will hold down the autofocus button, and all you will hear is the lens adjusting and readjusting itself.
With no sign of that comforting beep, it is time to focus manually. Hopefully, you should be able to make out some forms through your viewfinder. Turn your focus ring manually to make an accurate selection of the subject. Macro photography fans out there will already know the importance that manual focus brings. Macro photography involves taking images very close to the lens. It requires wide apertures.
And wide apertures give hardly any forgiveness when it comes to sharp focus. But it is where a majority of the creative aspects come from. Mastering manual focusing is a must for macro photography because it allows for a much greater range of experimentation. Focus stacking is a method to ensure that every element is in focus to its fullest.
It is often used in landscape photography, mainly by photographers who like the HDR process. This process is very similar to HDR. You have your camera on a tripod , take many images, and then stitch them together through post-production. You use manual focus to target each different aspect. This method is helpful because you will be able to take images on a wide aperture. Using a wide aperture will allow you to drop your ISO down, in turn producing sharper images.
It also allows you to take many photos to pick the best ones later when looking on a bigger screen. If you have been a photographer for a while, you will have identified situations where the autofocus system can fall short. The autofocus function looks for lines of contrast to find depth to base its measurements. E nvironments with a lack of different tones can force you to use manual focus. Use the techniques I wrote above to work through this issue. Especially if you only have a small window to get the perfect shot.
Hopefully, you know your subject well or can quickly assess how the subject will act. Preparation will allow you to measure out and take some test images beforehand. By using manual focus, you can get the sharpest image. Adjust the camera in manual focus and then wait for the subject to move by and snap. A panorama is an image where a whole landscape or skyline is presented seamlessly in one picture. Some cameras, as well as iPhones, have this feature embedded in their software already.
The manual way of doing this is to take a series of images and stitch them together in the post-photography process. If you were to take these images with an autofocus system, you would risk the focus adjusting.
If this happens, the viewer will notice it in the final result. The image will look disjointed, and the believability of the image being one seamless photograph will be lost entirely. I suggest focusing beforehand and then taking each image accordingly. Technology has come so far with its constant advancements in autofocusing capabilities. Still, there is no denying the importance of being able to use manual focus with confidence. The more you photograph, the more this will become clear.
But there will be times when you will be glad you studied this article. So turn that switch to manual focus, put your hand on the focusing ring, and get practising!
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