function blackout(idIB,min,max) {
    if (idIB<min) {idIB=max;}
    if (idIB>max) {idIB=min;}
    // xhr запрос
    var url='program/loadingOf.php?imgB='+idIB;parseInt(idIB)+1;
    xmlhttp.open("GET",url,true);
    xmlhttp.send();
    xmlhttp.onreadystatechange=function() {

    if (xmlhttp.readyState==4) {
        if(xmlhttp.responseText) {
            var resp = xmlhttp.responseText.replace('\r\n', '');
            if (resp!='') {
    var blackout = document.getElementById('blackout');
    blackout.style.width= screen.availWidth+'px';
    blackout.style.height=screen.availHeight+'px';
    blackout.innerHTML = '<img id="imgB" onclick="blackout('+idIB+','+min+','+max+');"/>';
    document.location.hash=n;
    var imgB = document.getElementById('imgB');
                imgB.src='photo/'+resp;
    imgB.style.zIndex='200';
    imgB.style.position='fixed';
    imgB.style.cursor='pointer';
    imgB.style.maxHeight=getViewportHeight();
    imgB.style.maxWidth=screen.availWidth-100;
    imgB.style.left=screen.availWidth/2-imgB.width/2+'px';
    imgB.style.top=getViewportHeight()/2-imgB.height/2+'px';
    var close = document.getElementById('close');
    close.style.left=parseInt(imgB.style.left)+imgB.width+'px';
    close.style.width=screen.availWidth-parseInt(close.style.left)+'px';
    close.style.height=getViewportHeight()+'px';
            }
        }
    }
}
}