How to use Non-Photo Blue Lead
Here's a quick primer on one way (of many) to remove non-photo blue from your final art using photoshop
Start with a full color scan of your art. We're assuming that you've used blue to sketch and black ink for the final render.
Step 1: Load the image into photoshop
Step 2: Navigate to Image>Adjustments>Black & White
Step 3: Slide the 'Cyan' option all the way to 300% and hit OK
Step 4: Export or save the image with these changes.