According to Sindone.org:
From 16 to June 18 the Shroud was exhibited at the Royal Palace, in the chapel of the Crucifix, to allow a study commission, appointed by Cardinal Michele Pellegrino , to carry out a survey on the Cloth. On that occasion were taken the first color photographs of the Shroud
Same day:
http://www.sitohd.com/siti/18854/foto/330048.jpg