There are a few ways to make the camera see infrared. The simplest way is just to take an infrared filter and place it on the lens, go outside with a tripod and start taking long exposure pictures.

However, this method is inconvenient, and it will make moving objects blurred.

Permanent Infrared and Full Spectrum Conversion

So we will do camera conversion. Basically, there are two types of infrared camera conversion: permanent infrared and full spectrum.

Permanent infrared is handy when we do not have infrared filters or adapters for each lens. It also allows us to see the subject through the viewfinder on a DSLR camera.

Full spectrum conversion facilitates us to try out new ideas and new filters. Perhaps, one day I want to shoot with a 590nm filter, and another day I want deep black with a 950nm filter.

We need then to buy infrared filters that fit our lens.

In all those two types the filter that blocks UV and IR light will be removed from the sensor.

Different cameras have a different number of those filters. Canon DSLRs and
mirror-less cameras usually have two filters.

Sony mirror-less cameras have one thick filter.

Fujifilm compact cameras have one filter, and Fujifilm mirror-less cameras have two filters.

New cameras have an ultrasonic sensor cleaning system. Some cameras like Canon 60D have very clever firmware and detects that this is not the original glass. It usually gives ERR 70. Disabling the automatic sensor cleaning system, in this case, makes the camera work properly again.

Infrared Filters

Some cameras are used for astrophotography. Those have a special filter that passes Hydrogen Alpha light. The filter for this purpose would be Astronomic.

There are a few infrared filters. The most well-known is the 720nm filter, often referred to as “standard” infrared. It gives a slight grayish image straight from the camera.