For printing Ilford Multigrade range of papers on unconverted black-and-white enlargers, Ilford have produced complete sets of 12 numbered filters for all contrast grades in half grade steps. Multigrade filters are supplied in 3 inch and 6 inch square sizes to fit most enlarger's filter drawers, and as a set of mounted filters for below-lens use with a filter holder. Multigrade filters do not require any recalculation of exposure times when changing between grades 0 and 3,5, grades 4 to 5 simply requiring twice the exposure. Individual 30 cms square filters are available to special minimum orders.