Yellow John Deere?

My photo club ventured to the Antique Gas and Steam Engine Museum up in Vista for this month's field trip. Only seven or eight of us showed up, but we still had a great time. It is hard capturing the movement of these still working machines using still imagery, but we did our best.

As part of this month's challenge, we were to submit the photos in black and white -- or at least monochromatic -- like sepia images. I almost did that -- as you view the album (via the link above) you can see mine have a bit of color to them. I just put a sepia layer in front of the color image, and then let 15% of the color image show through the sepia layer. I thought it a cool effect. What do you think?