Can anyone tell me if there is such a thing as a filter to change color photos to sepia toning?
You don’t need a filter; all you need is Photoshop’s built-in tools. There are many, many ways to do this; each may give slightly different results, so you have plenty of effects to choose from.
Any one of these techniques will work:
1. Use Image->Adjust->Hue and Saturation. Click on "Colorize" and move the Hue and Saturation buttons to taste.
2. Use the Color Picker to pick a color, then Edit->Fill with Foreground Color in Color mode.
3. Desaturate the image, then Image-.adjust->Curves.
4. Create a duotone. This gives you the most control; you can specify a black and sepia duotone that will allow you to mimic the effect of a real duotone with a great deal of precision and control.
5. Use Photoshop’s built-in Sepia action.
6. Create a Hue and Saturation adjustment layer.
7. Use the Channel Mixer.
8. Ceate a layer, fill it with color, and set its Blending Mode to Color.
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