Level 5 photography
Still Life
What is colour Profiles
Digital photography works by turning colours into numbers. There are different ways of doing so some use the physics of light waves, some rely on the way the eye perceives colour and some are uilt around the way the ink creates colours. To understand how to preserve colour as you change from one model to another, basic understanding of colour model is, it is that the colours turn into numbers with a mathematical formula. Colour profiles (or spaces) refer to the specific usage of colour model usually either a RGB colour mode or a CMYK colour mode.
RGB is a colour mode that uses the three primary (red, green, blue) colours which can be mixed to make other colours. RGB builds its model on different colours of light added together, where all three colours produces white light. RGB should be used for images that are going onto a website as the RGB profile is a very small colour space.
CMYK is a colour model based on subtracting light- the cyan, magenta, yellow and black inks used in most commercial colour printing.
CIELAB and CIEXYZ are similar colour models designed to approximate human vision, because these colour models have so many colour, both used when translating from one colour model, such as RGB, to another such as CMYK. Photoshop uses CIELAB as a referance colour space for editing images.
Working colour spaces are colour models that are well suited to image editing such as colour and tone adjustments, these are large colour spaces offering the photographer to choose a wide amount of colours.
- Adobe RGB (1998)- the colour space was created by Adobe in the late 90s, when photoshop implemented full colour management. Most DSLR cameras offer this as a colour space choice for JPEG. Adobe RGB does not contain as many colours as PRoPhotoRGB, it is easier to use and good coice fo both 8 bit and 16 bit image editing.
- ProPhoto RGB- This colour space designed for high bit image editing and includes colour the human eye can see and popular for experienced photoshop users.This colour space not always the best choice for working space as it is 15% of the colour space beyond the range of human vision.
- CIELAB- Some people have found interesting ways to use this colour space to manipuate images, however is not an easy space to use since its not natural for most people. images that are in CIELAB space also dont have full support in photoshop for adjustment layers.
Delivery Space
when images are sent from one person to another, the choice of delivery is often on what the photographer knows about the recipient of the image.
- SRGB- this is a small colour space, this makes a good choice to send but at the moment is only appropiate for uploading images on websites as browsers dont support any colour management.
- Adobe RGB- This is the most requested colour space for delivery. It offers a good range of colours if specifies and wide support. Adobe RGB images that are uploaded to website without conversion to sRGB will generally appear dark and gentle.
