Asian Handicap & Value help

If a team is +0 to +0.5 at even money.

£10 stake

Win: £10
Draw: £5
Lose: -£10

How do I work out what type of odds I am actualy getting?

I mean if a team to win was evens I would say they have a 50% chance of winning and I think they will win more than 50% of the time so I have a value bet in my eyes.

But on the asian example above I win half with a draw full ammount with a win and lose all with a defeat. Is there a way to work out if I have a value bet?