233559
The EOS flash system is capable of wireless multiple flash control , whereby a master flash unit IR ( ST-E2 ) or RF ( ST-E3-RT ) transmitter mounted on the camera body can control up to 3 ( optical ) or 5 ( radio ) groups of flash units .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None