Now that GenCon's done and the Neverwinter Campaign Setting is on the shelves, I can finally post the poster maps I created for it.
The process for these was similar to my typical work-flow, just on a larger scale. Like my other maps, I usually start in Photoshop with a rough outline forwarded from R&D or the author and begin developing the stylistic elements like textures and border treatments. Sometimes the maps are following an already established motif though. For example, in this case I was trying to stick with the flavor I have been developing already for my other Forgotten Realms maps. Once I have the working file set up with an outline, borders, text, textures, and a background, I then begin sketching my ink layers. I've created a series of custom ink brushes that allow me to hand draw the details of my maps. Once I'm progressing with the ink layers, if need be, I can cut and paste some elements in a randomized fashion making sure they don't look repetitive. I've also built a library of inked brush stamps that I can use to cut down the drawing time. In addition, I make sure that there aren't any gaps in object outlines if they will be colored separately, this way I can isolate them with a wand tool later on during the coloring phase.
Once the inked details are complete and all the text is placed, the file gets sent off for approvals/edits and then, barring any major revisions, I get down to painting. Again, In my opinion, custom brushes and textures are worth their weight in gold. At this point I usually build some quick alpha channels to separate out the major elements of the image and begin painting on multiple layers. Each map can have dozens of individual ink and color layers since keeping the artwork well organized allows me to edit, paint, and mask off portions of the image quickly and cleanly. I love playing with my layer and brush setting and probably use multiply and hard light almost as much as "normal".
Once the inks and general colors are finished, I take a long look at the image as a whole and try to address any overall color, contrast, or readability issues before forwarding on the final streamlined file to my art director.
So that's basically it. I could go into a lot more detail but would probably need a book to pack it all into.
Hope you like the artwork.