ACCURATE FILTER WHEEL
The Atik One 6.0 has an integrated filter wheel with a carousel mounted on axial needle roller bearings. Incorporating a filter wheel into a CCD camera has some useful advantages. External filter wheels add considerably to the backfocus of the system, causing spacing difficulties when also using focal reducers, field flatteners or coma correctors. The integrated filter wheel here only adds 14mm to the depth of the camera, giving a total backfocus of 27mm. As most correctors are designed for use with DSLR cameras – which have a total backfocus of nominally 55mm including their adaptor rings – this leaves a generous 28mm for the insertion of an off-axis guider as well, if required. It also means you need fewer cables, as the power and USB leads for the filter wheel are shared with the camera.
The filter wheel has five 1.25-inch slots and it is vital that these are centred accurately in front of the sensor as each filter is chosen in turn. During our bench testing, we found that the filters were very accurately positioned and repeatability was excellent.