diff --git a/galleryscript.js b/galleryscript.js
index ccf6b84..3ee1da1 100644
--- a/galleryscript.js
+++ b/galleryscript.js
@@ -107,6 +107,15 @@ function preload(i) {
         prestr='<img src="_med/med_'+encodeURIComponent(imagelist[left])+'.jpg" />';
         prestr+='<img src="_med/med_'+encodeURIComponent(imagelist[right])+'.jpg" />'; 
     }
+    maxThumb=getmaxthumbs();
+    ends=getThumbStartEnd(i+maxThumb,maxThumb);
+    for (n=ends.first; n<ends.last; n++) {
+        prestr+='<img src="_tn/tn_'+encodeURIComponent(imagelist[n])+'.jpg"/>';
+    }
+    ends=getThumbStartEnd(i-maxThumb,maxThumb);
+    for (n=ends.first; n<ends.last; n++) {
+        prestr+='<img src="_tn/tn_'+encodeURIComponent(imagelist[n])+'.jpg"/>';
+    }
     ob.innerHTML=prestr;
     preloadcheck();
     preloader=setInterval('preloadcheck()',100);
@@ -136,16 +145,13 @@ function thumblist(n,curr) {
     if (imagelist.length==0) { return; }
     ob=document.getElementById('thumbcontainer');
     ob.style.width=document.body.clientWidth-30;
-    startI=Math.max(0,n+1-Math.round((maxThumb/2)));
-    startI=Math.min(startI,imagelist.length-maxThumb);
-    startI=Math.max(0,startI);
-    endI=Math.min(startI+maxThumb,imagelist.length);
-    currentlist=endI;
-    nright=endI-Math.round((maxThumb/2))+maxThumb-1;
+    ends=getThumbStartEnd(n,maxThumb);
+    currentlist=ends.last;
+    nright=ends.last-Math.round((maxThumb/2))+maxThumb-1;
     nleft=nright-maxThumb-maxThumb;
     if (maxThumb%2==1) { nright+=1; nleft+=1; }
-    leftstr='<span title="[shift left arrow]" id="arrowleft" class="thumbbox" onclick="thumblist('+String(nleft)+','+String(curr)+')">&larr; <div class="arrowtext">('+startI+')</div></span>';
-    rightstr='<span title="[shift right arrow]" id="arrowright" class="thumbbox" onclick="thumblist('+String(nright)+','+String(curr)+')">&rarr; <div class="arrowtext">('+(imagelist.length-endI)+')</div></span>';
+    leftstr='<span title="[shift left arrow]" id="arrowleft" class="thumbbox" onclick="thumblist('+String(nleft)+','+String(curr)+')">&larr; <div class="arrowtext">('+ends.first+')</div></span>';
+    rightstr='<span title="[shift right arrow]" id="arrowright" class="thumbbox" onclick="thumblist('+String(nright)+','+String(curr)+')">&rarr; <div class="arrowtext">('+(imagelist.length-ends.last)+')</div></span>';
     menustr='<span id="thumbmenu" class="thumbmenu"><span id="allthumbs" class="menuitem" onclick="allthumbs()" title="show all thumbs">all thumbnails</span>'+
            '<span>Order:</span><span class="menuitem" id="sortalpha" onclick="sortlist(\'alpha\')">name</span>/'+
            '<span class="menuitem" id="sorttime" onclick="sortlist(\'time\')">time</span>/'+
@@ -153,7 +159,7 @@ function thumblist(n,curr) {
            '<span>Original:</span><span class="menuitem" id="originals" onclick="fliporiginals()">'+String(originals)+'</span>'+
            '<span>Fullscreen:</span><span class="menuitem" id="fullscreen" onclick="flipfullscreen()">'+String(fullscreen)+'</span></span>';
     thumbstr='<div><span class="headsmall">Images</span>'+menustr+'</div><div id="thumbrow">'+leftstr;
-    for (i=startI; i<endI; i++) {
+    for (i=ends.first; i<ends.last; i++) {
         thumbstr+='<span id="n'+i+'" class="imagebox thumbbox"><img class="thumbimage" title="'+titlestring(imagedesc[i])+'" onclick="showimage('+String(i)+')" src="_tn/tn_'+encodeURIComponent(imagelist[i])+'.jpg"><br/><a href="'+encodeURIComponent(imagelist[i])+'" target="_blank">'+nicestring((imagelist[i]))+'</a></span>';
     }
     thumbstr+=rightstr+'</div>';
@@ -173,6 +179,14 @@ function thumblist(n,curr) {
     return;
 }
 
+function getThumbStartEnd(n,maxThumb) {
+    startI=Math.max(0,n+1-Math.round((maxThumb/2)));
+    startI=Math.min(startI,imagelist.length-maxThumb);
+    startI=Math.max(0,startI);
+    endI=Math.min(startI+maxThumb,imagelist.length);
+    return {first: startI, last: endI}
+}
+
 function allthumbs() {
     // Shows all the thumbnails in the current folder
     ob=document.getElementById('thumbcontainer');