filtratura device for an enlarger or photo player

摘要

Colour filters (8) are connected to thermal conductors (30). The conductors have the form, e.g. of metal plates or foils, and each extends over the entire surface of the filter it is serving. The conductors have holes (30') and reduce the temp. in the region of the filters so that the range of temperatures over which the unit can be used without damage is increased. Higher temperatures can be withstood. Each filter (8) fits inside a hole in an opaque plate (15) that acts as holder. The thermal conductor (30) is attached to one side of the plate. A glass plate (8') may be attached to the other side of the plate in order to hold the filter into its hole if adhesive by itself is regarded as inadequate.