I have performed filter modifications on a number of DSLR cameras (Canon 450D, 700D, 1200D, 500D, 1000D, 1100D, Nikon D3100, and Fuji X-A1) for me and my colleagues. It involves the removal of the stock UV-IR filter, making the camera more sensitive to H-alpha wavelengths. This modification is helpful only when shooting targets with H-alpha emissions, as most DSLR camera’s standard (stock) filter blocks this part of the spectrum.
Take note of the shift in white balance (reddish hue), which is to be expected in this type of modification. Focus will be affected, your camera may no longer focus with compatible lenses unless you add a filter between the lens and the sensor, to address the shift in focus and to filter out UV-IR. If used with telescopes, you need a DSLR-to-telescope adapter and achieve focus using the telescope’s focuser.
Here are sample images taken with the cameras I have modified (posted with permission).
Related link: View all home-brewed DIY astronomy equipment
Night Sky in Focus © Anthony Urbano | Bacoor, Philippines
Night Sky in Focus 