If you enjoy shooting landscapes, the chances are at some time you will consider investing in a square filter system, such as the renowned LEE Filters system. Just about all lenses have a focusing ring, which is used when manually focusing for getting the image into sharp focus. Some lenses are manual-only focus, such as all Voigtlander and all Laowa Lenses at the time of writing. Manual-only focus lenses will only allow you to manually focus, which is done by turning the focusing ring clockwise or anticlockwise by hand.
The focus ring is typically found at the front of the lens, although it could be anywhere along the lens barrel. As you turn this ring it moves one or more of the optical lens elements inside the lens forwards or backwards, which brings different parts of the image into and out of focus. When using a lens in autofocus AF mode, internal motors in the lens move the focusing elements back and forward to get sharp focus on your chosen focal point.
Different manufacturers have different types of focus motors, which all perform the same task. Ideally you want fast and quiet focusing and some modern lenses use as many as four focus motors to achieve this. Having fast autofocus is particularly important if you shoot moving subjects, like sports or wildlife or pets and kids running around at a party. In these cases, you might need to switch focus from very near to very far away in a short time, as the subject moves about the scene.
Quiet autofocus is important for video in particular, as focus motor noises can be recorded if they are too loud, which could ruin the audio in your movie. Other examples of where focus motor noise could be disruptive might be if you are shooting an interior where noise echos around a room, for wildlife where it could scare away your subject, or at a wedding during the vows.
Out of the box, most cameras use the same techniques to gain focus when AF lenses are mounted. In the most simple method, focus can be achieved by half-pressing the shutter release button, which engages the focus motor s to hunt for the focus point you have selected.
There are also several other ways to get focus, depending on which type of camera you have. Many cameras let you use the rear LCD screen to achieve focus. If your camera has touchscreen control on the LCD you may be able to simply click the screen and it focuses on that point where you clicked.
This is very quick and can be useful when the camera is away from your face as you are evaluating the scene in front of you. This is arguably far quicker than using the shutter button and adopted by many photographers who work quickly for portraits, street, weddings or documentary for example. Other AF options include the incredible capabilities of the Canon EOS R3 , which can be calibrated to simply use the point where your eye is looking through the viewfinder to achieve focus on that point.
You just look at your subject and the camera focuses for you! Despite being autofocus capable, most AF lenses will usually still have a focusing ring on them, even if you never use it. The reason is because there are certain times when manual focusing the lens can be more accurate than using the camera to autofocus for you. An example might be when you are photographing a bird in a tree and the camera incorrectly focuses on a branch immediately in front of the bird, rather than the bird itself.
If this type of situation occurs, you may want to manually override autofocus and use the focusing ring and fine-tune yourself. You may wonder why some photographers still use manual focusing lenses, or AF lenses set to manual, as it might slow them down or be less accurate.
Surprisingly there are a number of reasons, which is why we wrote a blog post here about The Benefits Of A Manual Focus Lens , which is worth checking out. As well as a focusing ring, zoom lenses will also have a focal length ring. The purpose of the focal length ring is to enable the user to zoom between the various focal lengths available on that lens, bringing the subject nearer or further away in the frame.
Ideally the focal length ring will be smooth to turn by hand and will not require too great a twist to zoom throughout the available focal range. Some lenses offer the ability to adjust the torque of that ring, making it either smoother to twist, or adding more friction. The focal lengths available on a zoom lens are always described as the first set of numbers in the name of the lens.
Here are some examples of popular zoom lenses and which focal lengths they cover:. Many photographers will abbreviate a lens name to simply the focal length it offers. For example, you might be considering a mm lens, or a mm lens, so the many other elements of the lens names might be left off when talking about them.
Certain zoom lenses have a feature where they are able to override the focal length ring in a similar way to which focusing rings can be overridden between manual and automatic. This allows you to quickly go from any focal length within the mm to mm range in an instant, which can be far quicker than twisting the ring if you switch between subjects which are nearer and further away.
In this example below, you can see acceptably sharp imagery all around the frame, and even far off into the distance. Different tools for different jobs.
The aspect ratio of a lens is determined by the sensor size or film size of the camera with which it is intended to mount. If a lens is built for an APS-C size sensor, it will not line up correctly with a full-frame camera. Our video on aspect ratios shows you how different ratios are used for presenting final cuts of projects, but your camera lens aspect ratio cannot be changed, as it is baked in the construction of the lens.
As you noticed from the video above, your subject matter can help determine which aspect ratio is best for your project. Lens breathing is the amount of shift in your angle of view when focusing.
Can you imagine your frame composition changing while pulling focus in a scene? Less than ideal. Lens flaring is when light is scattered in a lens system, usually caused by bright lights that shine directly into the eye of the lens.
This is more prominent in anamorphic lenses than spherical lenses but it can be achieved with both types. Lens flares are often considered to be unwanted artifacts in your image.
But they can also add a visual texture to your imagery. If you know anything about J. Abrams' directing style, the first thing that comes to mind is his use of lens flares. Chromatic aberration is your lens failing to focus all colors to the same convergence point. This is one of those really advanced lens specs that professional cinematographers give attention. Bokeh is a term used to describe when a lens renders out-of-focus points of light. Even your custom bokeh will look a little different when using an anamorphic lens.
The throw is very important in cinema and television because you need to make pinpoint adjustments when pulling focus from one subject to another. The more degrees available, the more accurate your focus pull. Performing focus pulls with still photography lenses can also shake the lens, resulting in footage that may be deemed unusable during the edit. There are focus pull accessories for still photography lenses, but the actual focus throw will likely remain the same.
So, what does the camera lens do? Beyond focusing light to the focal plane, your camera lens creates the way your viewer watches your story. It changes the way you communicate with your audience. Beyond some lens quality and lens technology advancements, lenses have stayed the same for centuries. Create robust and customizable shot lists. Upload images to make storyboards and slideshows. Previous Post. Next Post. A visual medium requires visual methods.
This has some limitations of course. Many are manual focus, many with autofocus have been used for many years and may be worn out, including what powers them, lens mounts, connectors, etc.
But you can still find barely used lenses that. This is not to say there are not great DSLR lenses coming out every year because there are. While they may not have many new features there are only so many features a lens can have , as technology changes they become lighter, better performing, or less costly. Just make sure that when you start your lens collection, you do not fall into the trap of buying lenses with many different mounts, such as Nikon or Canon. You want to stick to one lens mount, for example Nikon, and use adapters that allow other brand lenses such as Canon on your camera.
These adapters are getting better every year, and while they may only give mechanical functions using a Nikkor lens, with modern lenses they may give you autofocus, light and other readings. Adapters should not be confused with tele-converters or macro rings.
These do not adapt to different mounts but rather affect the way the lens behaves. Macro extension rings on the other hand are just spacers which allow you to put your subject much closer to the lens and still have focus.
This is because the focusing range of your lens in decreased, no longer being able to focus at infinity. Camera bodies are also replaced often besides the fact that shutters dont last forever because camera technology evolves so quickly.
Camera manufacturers are in a high level of competition every year putting out new models that are better than last years, whether its the sensor, battery life, megapixel count, etc. What you should keep in mind when buying new lenses if you are serious about photography due to what i described so far is you should buy good quality lenses with quality features, such as a low number fixed aperture.
They will last if you take care of them, and you will be able to use them on different camera bodies. While im on the topic of budget, third party lens manufacturers such as Sigma, Tamron and Tokina make lenses for other camera brands and these can save you quite a bit of money, while keeping image quality good.
Always read lens reviews or try before buying, especially with third party manufacturers, to make sure you are satisfied with the photos. Now that you have a greater understanding about how a DSLR lens works, understanding which lens is right for you and why will be an easier task.
There are two main types of DSLR lenses:. These lenses have a fixed focal length meaning that you have to move around more when framing your shot. However, they are generally a much faster lens and produce a sharper image.
They also tend to be lighter which is great for travelling. These lenses have a varying focal length meaning that you can zoom in and out of a scene without having to move your location. Their flexibility can be a great asset although they tend to be much bigger and heavier than prime lenses.
Zoom lenses work on the idea that you are moving various lens elements inside the lens with relation to each other, whether by turning the zoom ring or pulling it forward or back.
This changes the focal length and the magnification power of the lens. While prime lenses can help quickly develop your photographic skills, if you are not sure what kind of photography you will be doing, a zoom lens can be a great option. Within these two types of lenses there are several different more specialised lenses available. Again, depending on the type of photography you are going to be doing will depend on which lens you should choose.
These are the lenses that allow you to capture the tiny and intricate details of a scene. Often used in photographing small creatures such as ants and spiders, flowers as well as abstract images. Macro lenses can be purposely built prime or zoom lenses or they can be classed as macro simply because their closest focusing distance is short.
The prime macro DSLR lenses will usually have a wider aperture and higher quality glass than their zoom counterparts, therefore producing a higher quality image. A more affordable option if you are just getting started is to choose a lens that also has a macro function. This means that you can still do your everyday photography but if an occasion to capture a macro image comes along there is no need to change the lens.
On the other hand, these types of lenses often have a longer focal length which will lower the quality of the image. If landscape photography is your thing then wide-angle lenses will be your bread and butter.
These lenses can often produce the images we find most visually fascinating as the lens can often distort what we see with our eyes in real life. This distortion, however, can be linked to the quality of the lens. With the top wide angle DSLR lenses giving little to no distortion or chromatic aberration whereas the more affordable will see more. You are able to correct for this in editing software. Wide angle DLSR lenses are available in both prime and zoom lenses with quality and affordability varying between the two.
To determine which is for you, first you need to think about what you will be using it for. For example, if you are shooting portraits where you are able to easily move yourself around to capture the shot then a prime lens maybe best. However, if you are shooting a live performance where you are in a fixed position a zoom lens is probably going to be a better option.
If you are looking to photograph subjects from far away, then a telephoto lens is for you. They are generally lenses that have a focal length of 85mm or longer and like the other lenses they come in both prime and zoom.
When it comes to telephoto lenses though, it is the zoom lenses that are the most popular. This is because the situations that you generally need a telephoto lens require a little bit of flexibility and a zoom lens gives you that. Zoom telephoto lenses are particularly popular with sports and wildlife photographers as they are able to follow a subject without having to move much themselves.
These lenses also tend to have image stabilisation features which can be really helpful. It helps cut down any shaking or vibrations which become more obvious at longer focal lengths. Your general purpose, all-round and kit lenses are great when you are just starting out. They allow you to do multiple different types of photography with just one or two lenses. This means you can figure out which kinds of photography you are most interested in before buying more specialised lenses.
They are also popular with event and wedding photographers where the act of changing lenses can mean missing a potentially amazing shot.
These lenses are generally zoom lenses and because they are built to do multiple different things the overall image quality is not as high as a prime lens. However, there is a huge variety with some even having the ability to go from a wide angle to a long telephoto! These wide apertures also allow more light into your camera, making them ideal for shooting in low light conditions. Lenses with larger focal lengths are called telephoto lenses and offer greater magnification when shooting subjects that are far away.
Macro lenses allow you to zoom in and focus on subjects at extremely close distances. This is ideal for magnifying insects, flowers or manmade objects and capturing them in extreme detail. It can be adjusted much like the irises of the human eye, which dilate or contract depending on the available light. In general, the smaller the F-stop, the larger the aperture opening, and vice versa. Aperture also controls depth of field, which is used to separate your subject from the background.
The relationship between these three functions is commonly known as the Exposure Triangle Basics. However, the trade off is that high ISO levels introduce digital noise to your images. This allows you to use the same camera body with a variety of different lenses.
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