
Originally Posted by
Juvenal
The white arrow points to the currently selected unit when it is off-screen.
As far as I know you can't switch it off. However, if you press ENTER, currently selected units are deselected, so you won't get the white arrow and you also won't have any units with green markers around their feet.
With a bit of judicious photo-shopping you can usually eliminate white arrows, but remembering to deselect before taking your screen-shot is the best solution.
thanks i never thougth of deselcting untis first ill do that from now on 
This is a screenshot from the rtw unit guide I'm writing i wish id started turning off the banners too I though it would help identify units and such for noobies reading my guide but it would look more natural without. See the white arrow on the right? also I'm not a photoshop whiz
i use this