Exactly.. CTO or CTS on the flash. The background goes a great blue. If the flash is too bright then it can reduce the effect of the gel, if not bright enough then the ambient will kill any effect from the gel. Doubling up the CTO and working in open shade can help.
outdoors just at night..
Yes! Cto on the flash, and color temp low to match. It creates a cool blue background
Exactly.. CTO or CTS on the flash. The background goes a great blue. If the flash is too bright then it can reduce the effect of the gel, if not bright enough then the ambient will kill any effect from the gel. Doubling up the CTO and working in open shade can help.