diff --git a/public/templates/data.tmpl b/public/templates/data.tmpl
index 16cebc7..12a8d98 100644
--- a/public/templates/data.tmpl
+++ b/public/templates/data.tmpl
@@ -9,9 +9,9 @@
   <link rel="stylesheet" type="text/css" href="{{public_url}}maplibre-gl-inspect.css{{&key_query}}" />
   <script src="{{public_url}}maplibre-gl.js{{&key_query}}"></script>
   <script src="{{public_url}}maplibre-gl-inspect.js{{&key_query}}"></script>
-  {{^isLight}}
+  {{^is_light}}
   <script src="{{public_url}}elevation-control.js{{&key_query}}"></script>
-  {{/isLight}}
+  {{/is_light}}
   <style>
     body {background:#fff;color:#333;font-family:Arial, sans-serif;}
     {{^is_terrain}}
@@ -23,9 +23,9 @@
     h1 {position:absolute;top:5px;right:0;width:240px;margin:0;line-height:20px;font-size:20px;}
     #layerList {position:absolute;top:35px;right:0;bottom:0;width:240px;overflow:auto;}
     #layerList div div {width:15px;height:15px;display:inline-block;}
-    {{^isLight}}
+    {{^is_light}}
     .maplibre-ctrl-elevation { padding-left: 5px; padding-right: 5px; }
-    {{/isLight}}
+    {{/is_light}}
   </style>
   {{/use_maplibre}}
   {{^use_maplibre}}
@@ -139,13 +139,13 @@
       })
     );
 
-    {{^isLight}}
+    {{^is_light}}
     map.addControl(
       new ElevationInfoControl({
         url: "{{public_url}}data/{{id}}/elevation/{z}/{x}/{y}"
       })
     );
-    {{/isLight}}
+    {{/is_light}}
     {{/is_terrain}}
     {{^is_terrain}}
 
diff --git a/public/templates/index.tmpl b/public/templates/index.tmpl
index acf094f..1d3a514 100644
--- a/public/templates/index.tmpl
+++ b/public/templates/index.tmpl
@@ -124,9 +124,9 @@
             {{/is_vector}}
             {{^is_vector}}
             <a class="btn" href="{{public_url}}data/{{@key}}/{{&../key_query}}{{viewer_hash}}">View</a>
-              {{#elevation_link}}
+              {{#is_terrain}}
             <a class="btn" href="{{public_url}}data/preview/{{@key}}/{{&../key_query}}{{viewer_hash}}">Preview Terrain</a>
-              {{/elevation_link}}
+              {{/is_terrain}}
             {{/is_vector}}
           </div>
         </div>
diff --git a/src/server.js b/src/server.js
index 3a1016e..468b713 100644
--- a/src/server.js
+++ b/src/server.js
@@ -571,15 +571,17 @@ async function start(opts) {
       data.is_vector = tileJSON.format === 'pbf';
       if (!data.is_vector) {
         if (
-          (tileJSON.encoding === 'terrarium' ||
-            tileJSON.encoding === 'mapbox') &&
-          !isLight
+          tileJSON.encoding === 'terrarium' ||
+          tileJSON.encoding === 'mapbox'
         ) {
-          data.elevation_link = getTileUrls(
-            req,
-            tileJSON.tiles,
-            `data/${id}/elevation`,
-          )[0];
+          if (!isLight) {
+            data.elevation_link = getTileUrls(
+              req,
+              tileJSON.tiles,
+              `data/${id}/elevation`,
+            )[0];
+          }
+          data.is_terrain = true;
         }
         if (center) {
           const centerPx = mercator.px([center[0], center[1]], center[2]);
@@ -698,7 +700,7 @@ async function start(opts) {
       is_terrain: is_terrain,
       is_terrainrgb: data.tileJSON.encoding === 'mapbox',
       terrain_encoding: data.tileJSON.encoding,
-      isLight: isLight,
+      is_light: isLight,
     };
   });