If you want to buy a lens for your DSLR or Mirrorless camera, but do not know how to choose the right lens for your need, you are at the right place. In this article, I am going to explain the types of lens and how to understand the specifications printed on the lens. This will help you to understand your lens better or take better buying decision.
Lens Specifications
When you want to buy a lens, the two primary factors you need to consider are the focal length and the aperture of the lens. If you do not know what is focal length and aperture, read this article before you read this article further – Photography basics.
Let’s try to understand the lens specifications based on the information printed on it with the example of above two images.
- Brand Name : The first image shows that this lens is made by Canon brand.
- Zoom lens or Prime Lens : The first image shows that this lens is a zoom lens, that means the focal length is adjustable on this lens by zooming it in and out.
- Mount Type : Every brand has different mounts for their DSLR Full Frame, DSLR Crop Sensor, Mirrorless Full Frame and Mirrorless Crop Sensor camera body types. The lens needs to corresponds to fit their respective camera body types. Generally Full Frame lens can be used on DSLR Crop Sensor cameras and Mirrorless Crop Sensor cameras with an adaptor, provided both the cameras are from the same brand. But the Crop Sensor lens will not fit on Full Sensor camera because Full sensor lens have bigger mount opening size compared to Crop Sensor lens. Similarly, the lens made for mirrorless body type will not fit on any other camera body types. When we use the DSLR Full Frame or Crop Sensor lens on Mirrorless Crop Sensor camera, its effective focal length is compensated with the adapter. But it can not be adjusted vice-versa. EF-M in first image and EFS in second image refers to different body mount types. We will cover the mounts types in Canon and Nikon in their respective blogs.
- Focal Length : The first image shows this lens has focal length between 15 – 45 mm. That means, you can zoom in or zoom out the lens between the range of 15 – 45 mm to get different angles of view. But suppose you have another lens which is 50mm prime lens and you want to change the view of angle, then you need to move forward or backward from the subject until you get your choice of angle of view.
- Aperture : All the lens have the aperture value mentioned on it. The aperture value tells us about the maximum amount of light, the lens can allow to enter the camera. In above example the aperture value is F3.5 – F6.3. This will change according to the focal length adjustments on your camera. So, you need to consider the kind of aperture you need for your niche photography before you make your buying decision.
- Stabilization option : STM printed on the first image confirms that this lens has image stabilization mechanism. You will also notice a switch to toggle image stabilization on and off in the second image. Image stabilization option in the lens reduces the amount of motion blur caused in an image due to camera shake while it was capturing the image. It is very helpful feature when you are taking hand held shots. If you are taking image on tripod, you can get stable images without image stabilization. STM options are more expensive than non STM options but it is worth spending little more money if you are looking for Professional quality images or videos.
- Manual and Auto Focus Modes : In the second image you will notice a toggle button to switch between auto focus and manual focus modes. Make sure to have same focus settings on your camera body and lens.
- Lens Protector or Lens Filter Diameter : In the first image the number 49mm tells, that when you are buying a lens filter or a protector, you should buy the same diameter as mentioned on the lens, otherwise it will not fit to this lens.
Types Of Lens
Lens can be categorized based on two main criteria like zoom lens and prime lens or based on different focal lengths. Even there are more lens types like macro lens.
Zoom Lens vs Prime Lens
Zoom lens has adjustable focal length and aperture, while Prime lens has fixed focal length and aperture. Both categories of lens comes in various focal length options.
Lens Types : Classification based on Focal length
Fish Eye Lens
The lens which has the focal length between 4mm – 14 mm are called Fish Eye Lens. They are basically ultra wide angle lens and they give the widest angle of view. But this type of lens is used for very specific creative purposes and they are very expensive too.
Wide Angle Lens
The lenses between 14mm – 35 mm focal length are called Wide Angle Lens. They are commonly used for architecture and landscape photography.
Standard Lens
The lens with focal length between 35mm – 85 mm are considered Standard Lens. Generally the kit lens which comes with camera are standard lens. They are general purpose lens and good for travel, street and portrait photography.
Short Telephoto Lens
The lens with focal length between 85mm – 135mm are called Short Telephoto Lens and they are also good for travel, street and portrait photography.
Telephoto Lens
The lens with focal length between 135mm – 300mm are called Telephoto Lens and they are used for sports, wildlife and action photography.
Super Telephoto Lens
The lens with 300mm+ focal length are called Super Telephoto Lens and they are used for sports, wildlife and action photography where you need to shoot the subject from too much distance like sports, wildlife, nature and astronomy.
Below image describes how the focal length of the lens effects the field of view or angle of view.
Macro Lens
Macro lenses are special kind of lens which allows you to reproduce a life size 1:1 image of your subject similar to human eyes. It means the size of the subject in real life is the same size as it is reproduced on the sensor. They are capable of capturing small details as tiny as the hair of an insect. It allows closer focusing distance to the subject as compared to standard lens.
They are expensive lenses and used for specialized closeup photography. They are also good for product photography of small items like jewelry where you need to capture very tiny details with clarity. Below image is an example of image captured with a macro lens. Macro lens also comes in various focal length.
You must check for macro 1:1 info printed on the lens if you are buying the macro lens. This gives the best result as compared to other ratio.
Some more important factors to consider while buying a lens
Generally if you are doing product or portrait photography consider using Prime lens. Though they have limitation of fixed focal length but they deliver much sharper images as they let in enter more light into the camera due to its’s minimal design.
The zoom lens has complicated mechanisms inside the lens that allows the lens to zoom in and zoom out. This mechanism, takes considerable space inside the lens and allows less light to enters the camera at the same focal length settings as compared to the prime lens. More light entering the camera means more details will be captured in an image.
Though there are third party lens manufacturers making good lenses and they are considerable cheaper but the native camera brand will always give better performance.
Though you can use the Full Frame DSLR lens on Crop Sensor DSLR or crop Sensor Mirrorless, the lens made for their respective body types will always give better performance.
For general purpose street and travel photography the standard zoom lens is a good choice due to its versatility.
I hope this article was helpful to you. If yes, please share!