Pairs Charting

I've been looking to chart a pair (DAX/FTSE100) in real time for pairs trading. I have tried IG index advance charting and can get both on the one chart. Does anyone know how to get the chart to display the relationship between the two as a single line ie price of DAX/Price of FTSE?

Thanks for any help

google Pairtrade Finder, their software will allow you to do this plus give you trading signals for the pair.

Thanks for that. I'll give them a try. Do you use them and are they as good as they say?