Newbie question about print settings

[perkin-warbeck]

I have an Epson SC-P400. I use it to print images from Photoshop. Say I have a grayscale mode document (Gray Gamma 2.2 profile). When I print the image, the print settings let me choose Grayscale or Color.

If I choose Grayscale, will the printer use only black ink?

If I choose Color, will the printer use color ink in addition to black?

If not, please tell me what Grayscale and Color mean in the print settings.

 

[Shadowman]

Most printers use some color to make gray mixes, as your printer only has black ink it would have to use some color to make gray.

 

[perkin-warbeck]

Most printers use some color to make gray mixes, as your printer only has black ink it would have to use some color to make gray.

I recently had some confirmation of what you say. I was printing a grayscale image on my P400 when the printer ran out of yellow ink (for some reason, it kept on printing). The image came out blue. If C=M=Y and you subtract Y, you get C=M which is blue. The image was a gradient from black to white, and I was surprised to see blue even in the deep shadows, which means the printer was not substituting as much K as I expected.