The Tribute to Chet Helms. Saturday April 30th 1994. Maritime Hall, Harrison Street, San Francisco, California. Artwork by Chet Helms. The New Riders of the Purple Sage. Squid Vicous of Journey. Big Brother and the Holding Company. Lights by Bill Ham and more. Artwork by Gary Grimshaw, the dog poster. This first printing poster was printed before the show and is very very nice. 13 x 18 7/8 inches. We are here to make people happy, thank you for your business.