Step 5: Paint Layer Mask To Reveal Background

■ Click the Owl layer in the Layers palette to make it the active layer and you now see the grain come back into the image.

■ Choose Layer >- Add Layer Mask ^ Hide All to create a new layer mask in the Owl layer.

■ Reset Default Foreground and Background Colors (D) by clicking the icon in the Tools palette. White should now be the foreground color.

■ Click the Brush tool (B) in the Tools palette. Click the Brush Preset Picker (the second box from the left in the Options box) to get the Brush palette shown in Figure 11.10. If you get a different palette, click the menu button in the Brush palette and choose Reset Brushes from the popup menu. Click OK to replace the current brushes with the default brushes.

■ Click the Soft Round 300 Pixels brush.

■ Make sure that the Options bar shows Mode set to Normal and Opacity and Flow set to 100%.

■ Click and carefully begin painting over the owl. As you paint, you are painting out the effects of the Gaussian Blur command and revealing the rest of the image as it was before Gaussian Blur was applied, which results in a sharp owl and a grain-less background.

■ You need to change the brush to Soft Round 35 Pixels so that you can paint back all of the feathers around the owl's ear.

■ If you decide that you want to add back some blurred image, click the Switch Foreground and Background Colors (X) icon in the Tools palette.

Black should now be the foreground color and as you paint, you paint the blurred layer back into the image.

■ Do not flatten the image until you save it as a PSD file with layers, as you are likely to want to make further modifications to the mask after you examine the effects of the Unsharp Mask. The first time I masked the owl, I did not do it carefully enough and found that I had sharpened grain around the edge of parts of the owl — a wholly unacceptable bit of masking! Having saved the file, it was simple to go back and fix the mask.

If you find that there is too much grain in the owl's feathers when applying the Unsharp Mask to sharpen the image, you may want to try adjusting Opacity in the Options bar. As you lower the Opacity setting, you begin to get a mix of the soft layer that was blurred and the sharper Owl layer. Using the Layer mask, you can get an optimal level of grain removal for all parts of the image.

Figure 11.2 shows the results of varying the Opacity level while painting the mask and after applying the Unsharp Mask. The midtones value was also adjusted a small amount by using Levels to darken the image.

This approach to removing noise worked well for this image. Other images may demand an entirely different approach. But you now know which blur filters to consider, how to check each channel, and how to use a mask layer to apply different levels of grain removal to an image. After some experimentation, you will be able to find a good approach for specific digital cameras or scanners, and for the level of grain due to specific ISO settings or film speeds. I also suggest that you visit this book's companion Web page to get a clickable list of vendors offering tools to remove grain and noise. Most vendors offer trial versions of their software so that you can see how well they will work on your images.

TECHNIQUE

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