A brilliant rainbow directed fans of the Sacramento Choral Society and Orchestra to their season end party on Saturday night. Reflected in the puddles lingering from the rainy day, the rainbow lent a hopeful sparkle to the gala at the Temporary Contemporary Gallery at 1616 Del Paso Blvd. Inside, aficionados of choral music enjoyed the company of singers, musicians and fellow music lovers. Partygoers strolled amid the captivating art installations and helped themselves to imaginative refreshments and an assortment of wines. A pianist played softly near the speaker’s podium, and the hum of happy conversation rose above the clink of stemware. Recordings were available for sale, including SC