More sophisticated software tends to implement sepia tones using the duotone feature. Edward Steichen coined the term "duotone solarization" to describe this new technique. The book is published by Aperture and contains 65 duotone images. It featured both monotone and duotone paintwork, as did the last of the Pathfinders. The first catalog had 16 pages of hand-drawn merchandise printed in duotone. He was instrumental in the development of Hamer's Duotone guitar. Persil's debut album "Duotone" was released on Transformed Dreams in 2004. The instrument, called the DuoTone, was conceived while Dantzig was at Hamer Guitars. Vessels carry the "Canada" 'federal wordmark', which incorporates the duotone version of the national flag. Other, larger versions made of plastic encasing lesser balls are called Duotone balls. Then in the 70s, they switched to a duotone airhorn.