diff --git a/lib/mbtiles.js b/lib/mbtiles.js
index fc7f3cf..dafc2a5 100644
--- a/lib/mbtiles.js
+++ b/lib/mbtiles.js
@@ -35,9 +35,7 @@ function MBTiles(uri, callback) {
 
 // Finds all mbtiles file in the filepath and returns their tilesource URI.
 MBTiles.list = function(filepath, callback) {
-    if (typeof callback !== 'function') {
-        throw new Error('Callback required as second argument');
-    }
+    if (typeof callback !== 'function') callback = noop;
 
     filepath = path.resolve(filepath);
     fs.readdir(filepath, function(err, files) {
@@ -53,9 +51,7 @@ MBTiles.list = function(filepath, callback) {
 // Finds an mbtiles file with the given ID in the filepath and returns a
 // tilesource URI.
 MBTiles.findID = function(filepath, id, callback) {
-    if (typeof callback !== 'function') {
-        throw new Error('Callback required as third argument');
-    }
+    if (typeof callback !== 'function') callback = noop;
 
     filepath = path.resolve(filepath);
     var file = path.join(filepath, id + '.mbtiles');
@@ -68,9 +64,7 @@ MBTiles.findID = function(filepath, id, callback) {
 // Retrieve the schema of the current mbtiles database and inform the caller of
 // whether the specified table exists.
 MBTiles.prototype.exists = function(table, callback) {
-    if (typeof callback !== 'function') {
-        throw new Error('Callback required as second argument');
-    }
+    if (typeof callback !== 'function') callback = noop;
 
     if (this.schema) {
         return callback(null, _(this.schema).include(table));
@@ -91,9 +85,7 @@ MBTiles.prototype.exists = function(table, callback) {
 
 // DB integrity check.
 MBTiles.prototype.integrity = function(callback) {
-    if (typeof callback !== 'function') {
-        throw new Error('Callback required as first argument');
-    }
+    if (typeof callback !== 'function') callback = noop;
 
     this.db.get('PRAGMA quick_check(1)', function(err, row) {
         if (!(row && row.integrity_check && row.integrity_check === 'ok')) {
@@ -108,9 +100,7 @@ MBTiles.prototype.integrity = function(callback) {
 // Sets the synchronous flag to OFF for (much) faster inserts.
 // See http://www.sqlite3.org/pragma.html#pragma_synchronous
 MBTiles.prototype.setup = function(callback) {
-    if (typeof callback !== 'function') {
-        throw new Error('Callback required as second argument');
-    }
+    if (typeof callback !== 'function') callback = noop;
 
     fs.readFile(__dirname + '/schema.sql', 'utf8', function(err, sql) {
         if (err) return callback(err);
@@ -286,8 +276,8 @@ MBTiles.prototype.getTile = function(x, y, z, callback) {
         'zoom_level = ? AND tile_column = ? AND tile_row = ?',
         z, x, y,
         function(err, row) {
-            if (err) callback(err);
-            else if (!row || !row.tile_data) callback(new Error('Tile does not exist'));
+            if (!row || (err && err.errno == 1)) callback(new Error('Tile does not exist'));
+            else if (err) callback(err);
             else callback(null, row.tile_data);
         });
 };
@@ -348,8 +338,8 @@ MBTiles.prototype.metadata = function(key, callback) {
     this.db.get('SELECT value FROM metadata WHERE name = ?',
         key,
         function(err, row) {
-            if (err) callback(err);
-            else if (!row) callback(new Error('Key does not exist'));
+            if (!row || (err && err.errno == 1)) callback(new Error('Key does not exist'));
+            else if (err) callback(err);
             else callback(null, row.value);
         });
 };
@@ -375,7 +365,7 @@ MBTiles.prototype.getInfo = function(callback) {
     },
     // Determine min/max zoom if needed
     function(err) {
-        if (err) throw err;
+        if (err) return callback(err);
         if (info.maxzoom !== undefined
             && info.minzoom !== undefined) return this();
 
@@ -389,7 +379,7 @@ MBTiles.prototype.getInfo = function(callback) {
         zoomquery.finalize();
     },
     function(err, rows) {
-        if (err) throw err;
+        if (err) return callback(err);
         if (rows) {
             var zooms = _(rows).chain()
                 .reject(_.isUndefined)
@@ -402,7 +392,7 @@ MBTiles.prototype.getInfo = function(callback) {
     },
     // Determine bounds if needed
     function(err) {
-        if (err) throw err;
+        if (err) return callback(err);
         if (info.bounds) return this();
         if (typeof info.minzoom === 'undefined') return this();
 
diff --git a/test/read.test.js b/test/read.test.js
index b16a00b..d723237 100644
--- a/test/read.test.js
+++ b/test/read.test.js
@@ -2,13 +2,17 @@ var fs = require('fs');
 var assert = require('assert');
 var MBTiles = require('..');
 
+
 var fixtures = {
     plain_1: __dirname + '/fixtures/plain_1.mbtiles',
     plain_2: __dirname + '/fixtures/plain_2.mbtiles',
     plain_3: __dirname + '/fixtures/plain_3.mbtiles',
-    plain_4: __dirname + '/fixtures/plain_4.mbtiles'
+    plain_4: __dirname + '/fixtures/plain_4.mbtiles',
+    non_existent: __dirname + '/fixtures/non_existent.mbtiles'
 };
 
+try { fs.unlink(fixtures.non_existent); } catch (err) {}
+
 exports['get metadata'] = function(beforeExit) {
     var completion = {};
 
@@ -211,3 +215,31 @@ exports['get grids from file without interaction'] = function(beforeExit) {
         assert.equal(status.error, 14);
     });
 };
+
+exports['get tiles from non-existent file'] = function(beforeExit) {
+    var status = {
+        success: 0,
+        error: 0
+    };
+
+    var mbtiles = new MBTiles(fixtures.non_existent);
+    mbtiles.getTile(1, 0, 0, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(0, 0, -1, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(0, -1, 0, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(1, 8, 3, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(-3, 0, 2, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(2, 3, 18, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(0, 0, 4, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(3, 8, 4, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(4, 8, 4, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(5, 8, 4, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(13, 4, 4, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(0, 14, 4, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(0, 7, 3, yieldsError(status, 'error', 'Tile does not exist'));
+    mbtiles.getTile(6, 2, 3, yieldsError(status, 'error', 'Tile does not exist'));
+
+    beforeExit(function() {
+        assert.equal(status.success, 0);
+        assert.equal(status.error, 14);
+    });
+};