gameScreen Zooming fun!

Hey guys, i have searched around on the forums and at least got started with making my display group “zoom” or scale at a certain point and time. When it zooms out it works pretty smooth, but getting it to zoom back in is very choppy. here is my code:

 if(event.target.type=="tire" and event.other.type=="zoomout" ) then  
 if ( event.phase == "began" ) then  
 cameraActive = false  
 gameScreen.xReference = tireObject.x  
 gameScreen.yReference = tireObject.y  
 transition.to( gameScreen, { time = 600, xScale=.50, yScale=.50, transition=easing.inOutExpo } )  
 end  
end  
 if(event.target.type=="tire" and event.other.type=="zoomin" ) then  
 if ( event.phase == "began" ) then  
 cameraActive = true  
 gameScreen.xReference = 0  
 gameScreen.yReference = 0  
 transition.to( gameScreen, { time = 600, xScale=1, yScale=1, transition=easing.inOutExpo } )  
 end  
end  

I am doing my gameScreen camera as shown in the EggBraker sample code. any ideas why zooming out would be ok and then zooming back in would act weird? it zooms back in to were it should, but it is not smooth whatsoever.
[import]uid: 19620 topic_id: 7842 reply_id: 307842[/import]