Are you in the right space…?
Colour space that is.
Colour management is some thing that all serious photographers need to be aware of. Put simply, colour management is a process that ensures consistency of colour appearance throughout your photographic workflow. Important aspects of colour management are colour space and color model. Commonly used colour models are RGB, HSL and CMYK. For the RGB color model, the color space can be visualised as a three dimensional object whose three axes are the values of the Red Green and Blue primaries respectively. Similarly for HSL, the axes would be Hue, Saturation and Lightness. If you’re having trouble visualising that – you’re not alone but hang in there! For comparing different color spaces, it is common to view a two dimensional slice from the 3D color space, typically at 50% luminance which represents the mid-tones of an image. An example of this is shown below.
Image copyright Cpesacreta at en.wikipedia
Various types of color space can be defined. In 1931, the Commission International de l’ éclairage (CIE) defined a reference colour space which represents the colors that can be seen by the average person with no sight problems (the horseshoe shaped are of color on the diagram above). Due to their physical limitations, most devices, are typically incapable of rendering all possible colours and have a device-dependent color space which shows which colors the device is capable of reproducing. Working color spaces, for example Adobe RGB and sRGB are used in image editing software to constrain colors to a standard workable range. The range of colors within a working space or device dependent space is called a gamut.
You can from the picture above that different color spaces occupy different areas of the colour model which brings me to the point of this blog. I use Lightroom for postprocessing the raw image files from my cameras. For use on the website or for sending them to other people they need to be turned into a more familiar format such as jpg or png. I had been having trouble getting accurate color rendition on images posted on my website and couldn’t work out why. Eventually I realised that I was exporting jpgs in the ProPhoto color space. While this is the largest color space and should give more accurate color rendition, for web images, this is only true if the browser is color space aware and many are not. To be on the safe side, always export jpgs for web use using the sRGB color space as this will give the most accurate rendition on browsers that are not color space aware.
Just so that you can see what I’m talking about, The two images below were exported using sRGB and Adobe ProPhoto. If they look the same, your browser is color space aware. If they look different, your browser is not color space aware and the sRGB image probably looks “better”; the Adobe ProPhoto image probably looks a little too dark and under-saturated and possibly has color shifts. Let me know what you see on your monitor.
Remember – make sure you are in the right space!