Exposure without flash meter

[Steve-T]

I am considering buying an ELB400 in particular with the new HS head for HiSync, however a flash meter can not be used above X sync.
So, as somebody who has only really used either speedlights off camera with TTL or studio lights for products I have as yet never used a flash meter and am wondering the most efficient way of controlling ambient light and exposing the subject correctly when time is short?
Forgive me if this is a dumb question

 

[HoppyUK]

Expose for ambient light as normal, then add flash to taste - basically trial and error. Needs a bit of practise, but not difficult.

The LCD image with blinkies enabled is your only guide to balance really. Need to be able to see it clearly, ie in shade.

 

[Phil V]

As above, there's little chance of a real measurement, just expose the ambient to taste, and then balance the flash with a little trial and error. It sounds hit and miss, but you can get an idea of your flash power in advance with some rigorous testing.

 

[Steve-T]

Thanks both that makes a lot of sense