aumentare alpha

[Lino80]

ho provato ad aumentare questo valore: "var baseopacity=30" ma non aumenta l opacità..cosa bisogna modificare?
grazie

<style type="text/css">

.gradualshine{
filter:alpha(opacity=30);
-moz-opacity:0.3;
}

</style>

<script type="text/javascript">

/***********************************************
* Gradual Highlight image script- © Dynamic Drive DHTML code library (www.dynamicdrive.com)
* This notice MUST stay intact for legal use
* Visit Dynamic Drive at http://www.dynamicdrive.com/ for full source code
***********************************************/

var baseopacity=30

function slowhigh(which2){
imgobj=which2
browserdetect=which2.filters? "ie" : typeof which2.style.MozOpacity=="string"? "mozilla" : ""
instantset(baseopacity)
highlighting=setInterval("gradualfade(imgobj)",50)
}

function slowlow(which2){
cleartimer()
instantset(baseopacity)
}

function instantset(degree){
if (browserdetect=="mozilla")
imgobj.style.MozOpacity=degree/100
else if (browserdetect=="ie")
imgobj.filters.alpha.opacity=degree
}

function cleartimer(){
if (window.highlighting) clearInterval(highlighting)
}

function gradualfade(cur2){
if (browserdetect=="mozilla" && cur2.style.MozOpacity<1)
cur2.style.MozOpacity=Math.min(parseFloat(cur2.style.MozOpacity)+0.1, 0.99)
else if (browserdetect=="ie" && cur2.filters.alpha.opacity<100)
cur2.filters.alpha.opacity+=10
else if (window.highlighting)
clearInterval(highlighting)
}

</script>

[Xinod]

cambia anche questi

.gradualshine{
filter:alpha(opacity=50);
-moz-opacity:0.5;
}