.boxgrid{ 
float:left; 
overflow: hidden; 
position: relative; 
}
.boxgrid img{ 
position: absolute; 
top: 0; 
left: 0; 
border: 0; 
}

.boxcaption{ 
float: left; 
position: absolute; 
background: #fff; 
height: 50px; 
width: 100%; 
opacity: 1; 
/* For IE 5-7 */
filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=100);
/* For IE 8 */
-MS-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
}
.captionfull .boxcaption {
top: 200px;
left: 0;
}
.caption .boxcaption {
top: 160px;
left: 0;
}