A DSLR now serves as my dedicated camera for astrophotography, which may be used with typical camera lenses for wide-field shots of celestial objects, or may be mounted onto a telescope for closeup shots of galaxies and nebulas. Read more.
The modification involves physically removing the “hot plate”, a kind of filter that blocks infrared light. Manufacturers install it in cameras in order to correct for the reddish hue inherent to CCD or CMOS sensors. Removing such filter makes the camera more sensitive to IR and as well as H-alpha wavelengths, which is particularly useful in deep-sky photography.