function imgpopup(url,width,height,alt) {
  var agt = navigator.userAgent.toLowerCase();
  var ver = parseInt(navigator.appVersion);
  if(agt.indexOf('msie')!=-1) {
    width = width+20
    height = height+30
  } else {
    width = width+16
    height = height+18
  }

  maxheight = screen.height - 60
  maxwidth = screen.width - 30
  posx=0; posy=0
  if(height>maxheight) {
    height = maxheight
    width = width + 16
  } else {
    posy = Math.round((maxheight-height) / 2)
  }
  if(width>maxwidth) {
    width = maxwidth
    height = height + 16
  } else {
    posx = Math.round((maxwidth-width) / 2)
  }

  content = "<html><head><TITLE>J.E.D. Digital Illustrations</title>"
  content = content+"</HEAD><body bgcolor=black scroll=auto>"
  content = content+"<table border=0 cellpadding=0 cellspacing=0 align=center width=100% height=100%><tr><td valign=center align=center><img alt='"+alt+"' title='"+alt+"' border=0 src="+url+">"
  content = content+"</td></table><P><BR><BR>
<table width="120%" height=140 leftmargin="0" VSPACE="0" HSPACE="0" cellpadding="0" cellspacing="0" border=0
style="position:absolute; left: 0px;  margin-right: 0px; margin-left: 0px"><TR><TD background="images/bottomtile.gif"><img src="images/spacer.gif" width="105%" height=140></td><TR></table>

</BODY></html>"
  popup=open('','popup','dependent,scrollbars,width='+width+',height='+height+',screenX='+posx+',screenY='+posy+',left='+posx+',top='+posy)
  popup.document.write(content)
  popup.document.close()
  popup.focus()

}
