ズーム赤外線レンズの製品機能

Zoom infrared lenses are more prone to halo than other types of lenses, so a suitable hood is indispensable. Sometimes the occlusion caused by the hood is not visible on the viewfinder screen of a single-lens reflex camera, but it can be displayed on the film. This situation is more obvious when shooting with a small aperture, and the hood is often used. Some lens hoods are effective at the long focal length end, but when zooming to the short focal length end, the photo will produce vignetting caused by occlusion that cannot be seen on the viewfinder screen. To Some zoom lenses need to turn two separate control rings, one to control the focus and the other to control the focus. The advantage of this structural layout is that once the focus is completed, the focus will not be accidentally changed by adjusting the focus. To Other zoom lenses only need to move a control ring, turn it to focus, and slide it back and forth to change the focal length. This "single ring" zoom lens is often faster and more convenient for operation, but it is usually more expensive. It should be noted that when changing the focal length, do not lose the sharp focus. Use the support appropriately. When using a focal length of 300NM or longer, the lens should be fixed on a support such as a tripod to ensure the stability during shooting.