Can I embed a watermark into an image using 16 or 32 bit color channels?
To enable digital watermarking, the image the watermark is being applied to has to be in 8 bit mode, i.e. having 8 bits per channel, color or grayscale. Though Adobe Photoshop can edit images with 8, 16 & 32 bits per channel the plug-in supports only the 8 bit per channel mode. 16 & 32 bit per channel images offer a larger color depth for high end color reproduction while the final web and print image formats only recognize 8 bit mode images. Once an image is ready or has been saved as one of these final formats is when you should apply the watermark.