Introduction to the use of infrared filter

When it comes to photography, everyone thinks of taking color or black-and-white photos, with many subjects, including scenery films, portraits, wildlife films and so on. An accidental camera quality incident brought infrared photography, a brand-new photography technology, into people's field of vision. Let Bian Xiao explain to you what infrared photography is and how to choose and use infrared filters now, so that everyone can take beautiful infrared photos.

What is infrared photography?

This word originated from Sony's F707 Red Gate incident, which has a perspective function. Because infrared rays are outside the frequency of visible light, human eyes can't perceive infrared rays, but our camera photosensitive elements can record them and interfere with the normal imaging we need. Therefore, general camera manufacturers will install a low-pass filter in front of the photosensitive element to reduce the entry of stray light and ensure normal imaging. So if we want to do infrared photography, we know that we need to put infrared light into the photosensitive element to prevent visible light from entering. There are two ways to realize this, one is to buy an infrared filter and install it on the lens, and the other is to modify the low-pass filter before the photosensitive element is modified. Because the modification may cause irreversible damage to the camera, only the infrared filter is introduced here.

Selection of infrared filter

The choice of filter should consider the production time and lens caliber of the camera you use at hand:

If you are a user who directly uses filters and is operating early camera models, such as Nikon D70, D 100, D50, Pentax istD, istDL, etc., you can choose infrared filters with frequencies of 680nm, 720nm, 760nm and 850nm.

If you are a user of Canon SLR cameras or other new SLR models, you need to choose infrared filters with frequencies above 720nm, including 760nm and 850nm.

How to use an infrared filter

Equipment should be prepared before infrared photography: digital camera, tripod, cable and our infrared filter.

First, we need to adjust the custom white balance of the camera. Select the camera manual exposure mode, focus on outdoor green plants, install infrared filters, and take standard proofs as custom white balance. If the 720nm band is used, the blank area in the photo will be amber, and the green plants will turn white or light blue.

Try to use a tripod during shooting, because the infrared filter will make the exposure time relatively long. In order to get a clear impact, you can use a tripod combined with cable release.

Because infrared light will shift the focus of the original visible light, the specific steps should be: setting the white balance of the camera, taking off the infrared filter, framing and composing, screwing on the infrared filter, and manually moving the focus back and forth. Finally, the exposure time required for shooting needs to be repeatedly operated according to different cameras and different infrared filters to get the basic rules.

Do you know the novel infrared photography through a brief introduction to Bian Xiao? I hope this article can make your photography more creative.