In colour neg film red has the least contrast of all channels, so the red filter idea may not be the best choice. It is also very easy to shoot the image unfiltered and add the filtration at the print stage. This will have more or less the same effect with some added bonuses. By exposing the film normally you will expose all layers. This gives you more detail, contrast and less grain. If you so decide you can make a variety of filtered images from the same neg (cyan, red, blue, violet, etc...) as well as a normal print.