Toning a monochrome image gives it a subtle tinge of color that changes the feel of an image and gives the photographer another opportunity to present their images in a different way. A sepia tone could be introduced to give an image a period feel, while very subtle warm or cold tones can completely change the atmosphere of a picture.
It took an expert darkroom technician to properly tone a print during the film era. Toning was also done not only as an artistic move but also as a way to preserve the image since tests showed that a good sepia-or selenium-toned print would last longer than a regular silver Black and White. In fact, it used to be said that a monochrome print wasn’t really a print unless it was selenium- toned. Today, toning or tinting your Black and White image is purely done for artistic interpretation and a few clicks on the computer is all that is required.
There are basically two types of toning -a general overall tone and a split tone. In a general tone, the entire grayscale is converted to the selected tint from the highlights to the shadows. In a split tone, only part of the tonal range is converted, meaning only the shadows or only the highlights are toned or tinted. Split tones are often subtle, and in the case of a sepia split, add a hint of warmth to the image. Split tones can also have two tints where the shadow will be tinted with one color and the highlights with another. Try a cool highlight and progress to warm shadow, or try the reverse, as it’s all a matter of experimentation to see what works best.
Hue Saturation Method – Colorize
Begin with the original image. Open the Black and White image that you want to be toned. Normally, images with texture and a wide range of tonalities are best for toning. This image is a good candidate because a warm tint may give it a period feel.
Colorize it. The easiest way to completely tone an image is via Hue and Saturation adjustment layer. Access this via Layer > New Adjustment Layer>Hue and Saturation. This will add an adjustment layer on top of your Black and White image. Make sure you check the box Colorize.
Setting it right. Simple playing with the Hue and Saturation sliders can get you different tints. Experimentation is the key.