colour filter

But its key innovation is that its pixels are arranged in groups of four, with each set sharing the same colour filter to detect red, green or blue light.

Users can jump to any particular time since the SDO launched in 2010, select a colour filter and retrieve the data.

In 2012 they re-examined a small part of the centre of the HUDF, this time with an additional colour filter and a time exposure totalling about 23 days.

Elmer was very much engaged in photographing flowers from nature through the ruled screen and colour filter—in experimenting with the Elmer process, in fact; by which the intermediate stage of a coloured negative is rendered unnecessary.