The lowest HEALPix order used in the MOC


This attribute controls the size of the largest hole or island that could be missed when adding Regions or pixel masks into a Moc using methods AST_ADDREGION or AST__ADDPIXELMASK. It gives the resolution of the initial grid used to identify areas that are inside or outside the Region or pixel mask, expressed as a HEALPix order in the range zero to 27 (this class does not support orders greater than 27). Unselected areas (i.e. bounded " holes" or or " islands" in the selection) that are smaller than one cell of this initial grid may be missed (i.e. such holes may be " filled in" and islands omitted in the resulting Moc).

The default value is (MaxOrder-4), with a lower limit of zero. For instance, if MaxOrder is 16 (a resolution of 3.2 arc-seconds), then MinOrder will be 12, meaning that bounded holes within selected areas may be filled in if the hole is smaller than 51 arc-seconds. Increase the value of this attribute to ensures that only holes smaller than this value can be missed. Note, doing so will increase the time spent creating the Moc.

To ensure no pixels are missed, set MinOrder to some very large value (larger than 27). If MinOrder is set greater than MaxOrder, the value of MaxOrder will be used whenever MinOrder is required.

The MinRes attribute is equivalent to MinOrder but expresses the resolution as a number of arc-seconds rather than as a HEALPix order. Any change made to MinOrder will cause a corresponding change in the MinRes attribute.



All Mocs have this attribute.