[brian wright22]

Yes in the "old " days Auto remote slave flash was easy using the internal camera front facing flash and the slave to bounce off the ceiling to remove the shadows or for a more creative lighting effect and with TTL metering. All syncronised with a simple photocell and thyristor built into the slave flash gun. Even the cheapest slaves (about £15) gave good results for fill slave flash!!.
But now with the Pre-flash required for the correct functioning of the digital cameras this can't be done unless you spend a lot of money.