by: Jerry Lodriguss
The relative hydrogen-alpha sensitivity of the Canon EOS 60D (left) and 60Da (right) can be compared in these images of M8, the Lagoon Nebula. The 60Da has a specially modified long-wavelength filter that transmits 3 times more hydrogen-alpha light than the standard filter in the 60D. This makes astrophotography of red hydrogen-alpha emission nebulae easier with the 60Da. The more pastel shades of cyan dominate the 60D image are from Oxygen III emissions in the nebula.