The other day I wrote about Black and White photography and the very next day, I got an email about the red filters. It seems that they are some of the least understood filters nowadays. Instagram users apply various filters, including red colored, at times to improve their selfies (a term which I fail to understand). Here in the article, I am talking about the true red glass that fits over the lens. They are also denoted by the Wratten numbers from 23A to 29.
What are these red filters and how are they used? First, let me clarify a few things. Instead of calling them red filters, they should ideally be called blue/green-inhibiting or blue/green-subtraction filter. That is exactly what they do.
Continue reading Red Filters (and other coloured filters)