Filters DSLR astro Conversion filter ( ACF 2) for Canon EOS 350 D/20 D improved spectral transmission! (flat-optically polished)

ACF I-III filters have a thickness of 2.7 mm, matching the effective thickness of the original Canon filters so, as far as possible, not to affect the focus adjustment.

The Baader AFC II also fits the Canon 10 and the 30D, however the original filter mounting is slightly larger so the conversion can be rather difficult - the small gap remaining must be filled with silicone sealant or similar. Functionality is however in no way impaired, as we can confirm from conversions based on our own 20D. Despite the larger filter of the 20D, the area effectively used by the image sensor is not greater as for the 350D