Solar icons

my solar setup is
(unable to get the image to paste into post so use link below to view( how do you put an image in a post, I tried the image insert no luck))

when in 5 to 40% zone the icon is overcast
when in 0 to 5% zone the icon is cloudyperiods
these appear to be the wrong way round

the % for the first couple of hours in the day and at the end of the day on sunny days drops off too soon, i have found the setting of 10 ok for most of day any ideas on how i can improve this. sensor in a glass jar and is at present getting the sun from sunrise to sunset