Is my Raydar antenna to close to my head?

[bigeasy1]

I know this will sound stupid to those of you who are familiar with radar,but I'm a rookie at it and need some advice.
I bought a Raymarine SL72 Plus radar last season and have been slowly getting used to it as we are out fishing.I've been running it on clear days so that I can get familiar with what things such as tankers,freighters,boats,rain etc.look like on the screen.
AS I do this I read the instruction book whenever I get the chance.
I think I know enough(hopefully) to be able to decipher targets if we get caught in fog,now that I've been using it.

The one thing I'm not sure of and stupidly never thought about until I recently read about is the distance from the antenna dome to us in the boat.
I have it mounted on my radar arch which is about a foot over our heads(when standing),and behind us if we are sitting at the wheel.Of course if we are sitting as we normally would be, the clearance is much greater.
Is this to close?,and could we be putting ourselves in danger.As you can see,I have it mounted on the arch,and not on an elevated mount.
Should I lift it higher,or is it ok the way it is.Maybe this picture will give you an idea.
Any help is appreciated.