How do you make pictures look black and white but still highlight a certain color..like red?

Basically I have been trying it in my Photoshop and it is not turning out..lol I mean I am really good at technology and stuff..lol I mean as well a computer science major should be..lol but I can not crack this..can you please help..How do you make pictures look black and white but still highlight a certain color..like red?
I have done this by copying the color item and pasting it in using MS Paint after the whole picture is b%26amp;w.





You have to have two pictures to do it my way. 1 B%26amp;W and 1 color.





Tip: when you go to paste it in, use the zoom tool to get an acurate paste.How do you make pictures look black and white but still highlight a certain color..like red?
b%26amp;w is often meant to be grayscale and not duotone bitmap,


with photoshop , you can open a copy of colored image, ~duplicate layer, then desaturate second layer to remove color, then erase areas on b%26amp;w , for color from lower layer to show through,


~if you were trying to get all of one color, use selection of color range on color photo layer, then select b%26amp;w layer then delete highlighted,


~you could also select areas to leave color, invert selection and adjust hue/ saturation,


~ you could also select areas with lasso tool and copy and paster over b%26amp;w image,





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Well some programs basically just come with a tool .. But i do it the 'hard way' i select the parts of the photo i WANT to be black and white , and click black and white . And i select around all the parts i want to keep color , and dont make it black and white