Image Errors Lesson Plan
Being able to recognize common errors in images is of great value to you as a professional photographer, as well as anybody working as a picture editor.
As a photographer, learning about common erros helps you to avoid them yourself, but also your knowledge becomes an asset to your employers or to your clients as you can correctly identify problems in images of others - work colleagues, images sourced from picture libraries, images provided by the public and so on. This means you are starting to gain skills expected of a picture editor.
Image errors introduction
Cleaning damage
Colour channels
Interpolation
Over compression
Over sharpening
Posterization
Damaged colour profiles
Printing colour profile errors
Website colour profile errors
Other problems
Image errors introduction
There are many ways that technical faults, file damage and correction errors can appear in images. It is important to be able to identify these problems so that the images can either be corrected, or rejected should the errors be too severe.
Cleaning damage
Errors can be introduced by yourself or others attempting to clean an image and incorrectly using the tools.
Colour channels
Clipping of colour channels is a common error that introduces unreal colours or banding into an image.
Over compression
Over compression presents in a number of ways. Being able to recognize them will help you avoid the pitfalls of over compression and enable you to help others.
Posterization
Posterization is recognized by banding and a loss of subtlety and nuances in the transition from one colour to another.
Damaged colour profiles
Damaged colour profiles can result in damage and obscure warnings when you attempt to open the image with the damaged profile.
Printing colour profile errors
An inconsistency in colour rendition between the original scene, the digital file and printed versions of the image may indicate a lack of colour profiling or errors in colour profiling.
Website colour profile errors
Images can look vastly different when placed on the Internet, if not correctly managed.
Up to Digital Imaging
Back to Setting Up Photoshop
On to Colour Correction
