This is a question I get a lot, so here is a public answer:
Q: Do you do anything in particular to make sure your watercolor scans are true to the real color? I have issues keeping colors. -Mark Thisse
A: From my experience of digitally displaying watercolors for a while now, I’ve completely pegged it on the scanner. Watercolor papers usually have a texture and/or wrinkles. I’ve noticed that the different qualities of scanners, depending on the angle and type of light used to capture the image, can either highlight the textures or lessen it. I also think the type of light a scanner uses, whether it’s slightly whiter or yellower, also plays a role. (Think of normal lightbulbs vs. daylight bulbs.)
My personal scanner is the Epson Perfection V500 Photo scanner, and it’s been the absolute best to me. This scanner was made for scanning photo film to enlarge shots, so part of me thinks that it’s really built to handle color quality well. Also, in terms of hardware, I think the light the scanner uses must be very perpendicular to the bed, rather than at another angle. I came to this conclusion because I don’t have the trouble I occasionally face, which is a very highlighted / shadowed textured surface in my scans. This can lead to weird colors as well. (I always scan into Photoshop at 300 dpi or higher, which is also worth noting. I don’t allow any scanning software to make color alteration choices for me.)
This is all completely my own conjecture however, from my experiences with past scanners, and borrowing friends’. I could be full of shit. All I know is the Epson Perfection V500 Photo scanner has been a complete doll to me for years.
(Let me also add that I use thick watercolor paper for my work. I think if you use thinner paper, even if it looks okay in person, can get scanned wrong. Think of it like putting your paper onto a light table for tracing— it’s possible the colors can get muddied when the scanner’s light passes through the color as well as the thin paper, capturing the two ingredients, rather than just capturing the color on the exterior of the sheet. (This is also just another conjecture.))