PS-CFP2 can be effectively photoactivated by UV-laser line only. Dendra2, on the other hand, can be photoactivated using either violet or blue light, through either arc lamp or laser light irradiation.
PS-CFP2 can be used in combination with red or far-red fluorescent protein for dual color labeling. Dendra2 cannot be combined with green or red fluorescent proteins, since it occupies both green and red channels. It cannot be combined with blue fluorescent proteins either, since they require violet light excitation, which causes photoactivation of Dendra2.