Sumix SMX-M7xx - Manual (Page 71)

IR-cut Filter : How to Use
71 SMX-M7xx Series USB2.0 Camera User Guide
Another reason for using the IR-cut filter is the limited color correction for many lenses.
A lot of lenses have different depth of focus for visible and infrared spectrum. The IR-cut
filter cuts away a significant amount of the overall collected light and thereby affects the
sensitivity in a negative way. In general, color cameras are one factor less sensitive
compared to monochrome (depending on the sensor). This is primarily due to the IR-cut
filter.
Note: When the camera is used with the IR-cut filter, the focus distance is increased to 0.66mm. To restore the focus dis-
tance to the original value (when the camera is used without the IR-cut filter ring and ring-adapter) we suggest
using a ring-adapter:
How to Use
Usually the camera is supplied with the IR-cut filter screwed in.
The procedure of screwing the IR-cut filter in, and using the ring-adapter is described
below.
Install the IR-cut filter in the following way:
1 Remove the cover from the camera.
2 Put the IR-cut filter to the camera so that two holes of the filter are on top: