Reading the manual for the sx160is PowerShot. Found, on p. 158 mention of the HF-DC2 flash. The word "wireless" is used. A lot of speedlights operate from the on-camera flash, or an IR signal from that flash. Is that what is meant by "wireless", or does the sx160is put out a radio signal?
Where do I find a more complete description? Canon's website is very weak on description of it.

