- Software used: Corel Paint Shop Pro X3
- Time taken: 5 minutes.
Sometimes when you take a photograph and play around in an image editing program you get a desired effect, but because of the extent of your changes you add unwanted artefacts.
In this example of a colour shot taken in dunes at Redcar I wanted a moody black & white. So I used Lightroom's colour filters to adjust the tones in a converted greyscale image. It all looked good until I spotted the posterisation in the sky.
|This shows the original banding in the sky can be masked using noise
Posterisation is where the tones are compressed so that there's no longer a smooth range of tones and instead a stepped range which shows as harsh shaped patterns. This is known as banding and is always worse on large areas of similar tones such as sky. This can be rescued by adding noise.
Step 1: Select the Noise filter
With your image open in Paint Shop Pro X3 select the Noise filter from the menu Effects > Effects Browser. Click on the Add Noise from the left hand menu and Add Noise Factory Defaults from the right pane. When this is selected click on Modify.
Step 2: Modify the Add Noise filter
In the palette that pops up make sure Gaussian is selected and tick Monochrome. Then adjust the Noise percent to a suitable level. It's default is 50% which works well on this shot. Higher makes the noise more noticeable a lower percentage makes it more subtle, and the original posterisation shapes may still show.
You could choose one of the presets in the drop down Settings list. Here there are three Photo settings to simulate film grain.
You've read the article, now go take some fantastic images. You can then upload the pictures, plus any advice and suggestions you have into the dedicated Photo Month forum for everyone at ePHOTOzine to enjoy.