Noise Removal with Lightness Channel in Photoshop

This is the age of mobile phones. You can even take photos with them. But as for quality, it leaves much to be desired. There is a lot of color noise But there is a way to remove the color noise with the Lightness channel in Photoshop and some other tweaks. Let me show you how.

Step 1 : This is photo of my daughter taken with a mobile phone. Let us see what it looks like in close up.

Step 2 : I have zoomed into the image. You can see that apart from the yellow color cast there is a lot of noise.

Step 3 : Press ALT+CTRL+I. This dialogue box opens. The resolution is at 300 pixels. This is important. Let us increase it.

Step 4 : Increase the Resolution to 600 pixels/inch. Note that the Width and Height changes. In the menu drop down at the bottom click on Bicubic Smoother. Click OK.

Step 5 : Go to Image>Mode>Lab Color.

Step 6 : Duplicate the Background by pressing CTRL+J.

Step 7 : Switch over to the Channels palette. It is next to the Layers palette.

Step 8 : Click on the Lightness channel.

This is how the image looks.

Step 9 : Go to Filter>Noise>Reduce Noise.

Step 10 : The Reduce Noise Filter dialogue box opens.

Step 11 : This are the settings I have given on the panel at right. Click OK.

Step 12 : Press CTRL+A (select ALL), then CTRL+C (Copy). A selection of marching ants surround the edges of the image.

Step 13 : Go back to the Layers palette. Click the New Layer icon and a blank new Layer 2 forms.

Step 14 : Press CTRL+V (Paste). The Lightness Channel copy is pasted into Layer 2.

This is how the image looks.

Step 15 : Change the Blending Mode of Layer 2 to Soft Light.

This is how the image looks.

Step 16 : Press CTRL+E twice. The two layers will merge into the Background layer.

Step 17 : Switch back to the Channels palette and click on Channel b.

Step 18 : Reapply the Reduce Noise filter with the same settings as earlier.

Step 19 : Press CTL+A, then CTRL+C. A selection of marching ants selects the image.

Step 20 : Click back on the Layers palette. Click the New Layer icon. A new Layer 1 forms. After the New Layer forms press CTRL+V. The copy of the channel is pasted into Layer 1.

Step 21 : Change the Blend Mode to Soft Light.

This is how the image looks.

Step 22 : Press CTRL+E. The two layers merge into the Background Layer.

Step 23 : Go to Image>Mode>RGB Color.

Step 24 : Go to Image. In CS4 you will find the options, Auto Tone, Auto Contrast and Auto Color. In earlier versions you will find it under Image>Adjustments. Apply Auto Tone first. See if it works. If it does not press CTRL+Z to undo it. Try Auto Contrast and Auto Color in turn.

Step 25 : Auto Color works for me. Some of the yellow color cast has been removed.

Step 26 : Click the Eye Dropper Tool.

Step 27 : I have clicked on a pink shade with the Eyedropper.

The Foreground Color immediately changes to the color picked.

Step 28 : Press CTRL+SHIFT+N. The New layer dialogue box appears. Change the Opacity to 30% and the Mode to Color and click OK.

Step 29 : Click on the Brush Tool. Then click in the top panel to reveal the Brush palette. Set the Hardness to 0. You can change the Master Diameter of the Brush with [ (left bracket to make it smaller and ] (right bracket to make it bigger).