External filters can be used to enhance a black and white film image
I understand that such filters can also be used with digital camera
But, If I use, say a red external filter, then the resulting image on my D50 has red cast
Converting that image to a monochrome image in ps gives a blurry image
However, If I convert a non-filtered image using Photoshop's Channel mixer and Photo filter I get an 'acceptable' monochrome image.
So can external B&W filters be used to enhance a monochrome version of a digital image?