Beginner’s Guide to the Basics of Understanding Camera Lenses
A camera lens comprises many glasses (Concave, Convex, Concavo-convex, etc.) placed in distinct groups to provide uniform picture sharpness. The illustration that follows depicts the inside of the lens.
It also has an opening called “Aperture,” which may be regulated by camera functions.
- The lens specification comprises all pertinent information about the lens. Some of these parameters are printed directly on the lens for easy reference. The primary components of the standard are listed below. We shall split the specification based on whether or not the information is printed on the lens body.
- Available lens Specification information on the lens body
Focal length Spectrum Camera Lenses
A lens’ focal length may be fixed or changeable. It will be indicated in millimeters on the lens body. For e.g. 50mm, or 100mm – 400mm, etc. There is no zoom ring on a lens with a fixed focal length. Hence the focal length cannot be altered.
However, minimum and maximum focal lengths are specified for lenses with a changeable focal length. For 100mm-400mm lenses, the minimum focal length is 100mm, and the maximum focal length is 400mm. You may choose a picture with a focal length between these options.
Capable aperture Camera Lenses
Depending on focal length, the aperture resides inside the lens and may be constant or changeable. An illustration facilitates comprehension. For example, a lens with the specifications 100mm–400mm, F4.5–F6.3 (printed on the lens body), has a minimum F-number of F4.5 at 100mm and F6.3 at 400mm.
The F-number range would vary from 100mm to 400mm, ranging from F4.5 to F6.3. Zoom lenses with fixed aperture ratings are available, such as 24-105mm F4.0. Both 24mm and 105mm have an F4.0 aperture value.
MF/AF Camera Lenses
Manual focus (MF) and autofocus (AF) options are also available on lenses (AF). There is a swap that toggles between the two alternatives. In manual focus mode, the focus ring must be moved manually. This is particularly helpful when the autofocus is not precise or as intended.
In AF, the lens will automatically focus on the in-camera-selected focus points. Generally, we utilize AF mode since it is acceptable for most scenarios and much faster than manual focus.
Image stabilization Camera Lenses
An inbuilt mechanism of lens movement called image stabilization somewhat offsets handshaking. Some lenses provide the advantage of three F-stops due to image stabilization. Different lens manufacturers use various terminology for image stabilization. Here are some of the most often-used manufacturer-specific terms:
- Canon – IS – Image Stabilization
- Vibration reduction on Nikkor/Zuiko VR lenses
- Sigma – OS – Optically Stable
- Tamron VC stands for Vibration Correction.
Each phrase has the same meaning. This capability becomes very handy at longer focal lengths (beyond 200mm) because even the slightest handshake causes photos to blur. However, it drains considerable battery life and must be turned off when using a tripod.
The superiority of lens
Different lens manufacturers also use notifications to remark on or emphasize the lens’s superior quality. Higher quality implies that the glass parts of the lenses minimize lens flaws, that the lens is weather-sealed, and that the price is high.
Canon, for instance, uses a red ring or white structure to indicate that the lens is of superior quality. Similarly, “ED” on Nikkor lenses denotes “Extra-low Dispersion” glass inside the lens.
Filter mount Camera Lenses
Every lens requires a specific-sized filter. This information is legible through the lens’ front surface. There is lettering on the edge of the front window. We have industry-standard filter diameters (e.g., 52mm, 58mm, 62mm, 77mm, 95mm, etc.), and most lenses are compatible with them.
Type of motor for focusing
Canon lenses also indicate whether the lens has a separate focusing motor for quick and precise focusing. This is indicated by the abbreviation “USM,” which stands for “Ultra Sonic Motor.”
Minimum distance for focus
The lens surface’s minimum focusing distance is listed in feet and meters (e.g., 0.45 m/1.5 ft). This indicates that the subject must be at least this far away for the lens to focus. Occasionally, individuals go too near and then wonder why the lens is not focusing.
They even attribute it to a lens fault. Nonetheless, it is not a flaw. Keeping the minimum focusing distance in mind would be ideal.
Understanding DSLR Camera Lenses: The Basics
Various types of mounts
Mounts for cameras (manufactured by the same manufacturer) are also of various sorts, and their use is restricted in some way. E.g.
Canon has both an EF and an EF-S mount. The EF mount is compatible with full-frame and APS-C digital single-lens reflex cameras. However, the EF-S mount is incompatible with full-frame bodies. EF-S lenses are less expensive than EF lenses and are designed for hobbyists and amateurs.
Nikkor produces FX, DX, and CX lenses for full-frame, APS-C, and mirrorless cameras. Although there are no restrictions on the use of FX and DX mount lenses on full-frame or APS-C cameras, a DX mount on a full-frame camera provides the same field of view as an APS-C camera (i.e., restricts the view). CX mount is designed only for mirrorless cameras and is incompatible with full frame and APS-C cameras.
Full-time manual focus
In addition to AF mode, some lenses (often high-end lenses) provide parallel MF mode. This implies that the focus ring may be adjusted while in AF mode. Not feasible with less expensive lenses.
Count of aperture’s blades
The greater the number of aperture blades, the smoother the bokeh circles. Compared to low-quality lenses, which contain between 5 and 6 blades, higher-quality lenses have more than eight blades.
The lens’s weight
For handheld use, the lens’ weight is an essential consideration. Long zoom lenses and weather-sealed lenses often weigh more. When comparing identical lenses, the weight must be considered.
Long focal lenses (400mm, 500mm, and higher) are cumbersome. Typically, a tripod is required to utilize them. However, you cannot put your camera on a tripod (as is customary) with such a hefty lens since it may cause the camera and lens to become unbalanced and perhaps fall off.
These lenses incorporate tripod collars about one-third the distance from the camera to address this issue. You may attach a tripod head and utilize the setup with this collar. This significantly improves the balance.