diff --git a/CMakeLists.txt b/CMakeLists.txt
index 24f8b2a..6da84af 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -34,6 +34,7 @@ set(TENMON_SRC
     src/database.cpp src/database.h
     src/databaseview.cpp src/databaseview.h
     src/delete.cpp
+    src/filemanager.h src/filemanager.cpp src/filemanager.ui
     src/filesystemwidget.cpp src/filesystemwidget.h
     src/histogram.cpp src/histogram.h
     src/httpdownloader.h src/httpdownloader.cpp
@@ -77,7 +78,7 @@ endif()
 qt_add_executable(tenmon WIN32 MACOSX_BUNDLE ${tenmon_ICON} ${TENMON_SRC})
 
 find_path(FITS_INCLUDE fitsio2.h PATH_SUFFIXES cfitsio REQUIRED)
-target_include_directories(tenmon PRIVATE ${FITS_INCLUDE} ${CMAKE_BINARY_DIR} ${libXISF_SOURCE_DIR})
+target_include_directories(tenmon PRIVATE ${FITS_INCLUDE} ${CMAKE_BINARY_DIR} ${libXISF_SOURCE_DIR} "src")
 
 option(COLOR_MANAGMENT "Enable sRGB framebuffer support for gamma correct images and color profiles support" ON)
 if(COLOR_MANAGMENT)
diff --git a/src/filemanager.cpp b/src/filemanager.cpp
new file mode 100644
index 0000000..2e19c93
--- /dev/null
+++ b/src/filemanager.cpp
@@ -0,0 +1,178 @@
+#include "filemanager.h"
+#include "ui_filemanager.h"
+
+#include <QSettings>
+#include <QStandardPaths>
+#include <QDesktopServices>
+#include "loadimage.h"
+
+FileManager::FileManager(const QSet<QString> &openFilter, QWidget *parent) : QMainWindow(parent)
+    ,ui(new Ui::FileManager)
+{
+    ui->setupUi(this);
+
+    ui->leftTab->setOpenFilter(openFilter);
+    ui->rightTab->setOpenFilter(openFilter);
+
+    connect(ui->leftTab, &DirView::dirChanged, ui->leftPath, &QLineEdit::setText);
+    connect(ui->rightTab, &DirView::dirChanged, ui->rightPath, &QLineEdit::setText);
+    connect(ui->leftTab, &DirView::openFile, this, &FileManager::openFile);
+    connect(ui->rightTab, &DirView::openFile, this, &FileManager::openFile);
+
+    QStringList standardLocations = QStandardPaths::standardLocations(QStandardPaths::PicturesLocation);
+    QString picturesPath;
+    if(standardLocations.size())
+        picturesPath = standardLocations.first();
+
+    QSettings settings;
+    ui->leftTab->setDir(settings.value("filemanager/leftTabPath", picturesPath).toString());
+    ui->leftTab->header()->restoreState(settings.value("filemanager/leftTabHeader").toByteArray());
+    ui->rightTab->setDir(settings.value("filemanager/rightTabPath", picturesPath).toString());
+    ui->rightTab->header()->restoreState(settings.value("filemanager/rightTabHeader").toByteArray());
+    restoreGeometry(settings.value("filemanager/geometry").toByteArray());
+
+    setAttribute(Qt::WA_DeleteOnClose);
+}
+
+FileManager::~FileManager()
+{
+    QSettings settings;
+    settings.setValue("filemanager/leftTabPath", ui->leftTab->dir());
+    settings.setValue("filemanager/leftTabHeader", ui->leftTab->header()->saveState());
+    settings.setValue("filemanager/rightTabPath", ui->rightTab->dir());
+    settings.setValue("filemanager/rightTabHeader", ui->leftTab->header()->saveState());
+    settings.setValue("filemanager/geometry", saveGeometry());
+    delete ui;
+}
+
+QCache<QString, ImageInfoData>* DirFileSystemModel::getCacheInstance()
+{
+    static bool init = true;
+    static QCache<QString, ImageInfoData> cache;
+    if(!init)
+    {
+        cache.setMaxCost(10000);
+        init = false;
+    }
+    return &cache;
+}
+
+DirFileSystemModel::DirFileSystemModel(QObject *parent) : QFileSystemModel(parent)
+{
+    _cache = getCacheInstance();
+    setFilter(QDir::AllEntries | QDir::NoDot);
+}
+
+void DirFileSystemModel::setDir(const QString &path)
+{
+    _dir = index(path);
+}
+
+QString DirFileSystemModel::dir() const
+{
+    return fileInfo(_dir).canonicalFilePath();
+}
+
+Qt::ItemFlags DirFileSystemModel::flags(const QModelIndex &index) const
+{
+    return QFileSystemModel::flags(index) & ~Qt::ItemIsEditable;
+}
+
+int DirFileSystemModel::columnCount(const QModelIndex &parent) const
+{
+    return QFileSystemModel::columnCount(parent) + 1;
+}
+
+QVariant DirFileSystemModel::data(const QModelIndex &index, int role) const
+{
+    if(index.column() >= QFileSystemModel::columnCount() && role == Qt::DisplayRole)
+    {
+        QFileInfo info = fileInfo(index);
+        QString path = info.canonicalFilePath();
+        QString suffix = info.suffix();
+        ImageInfoData *infoData;
+        if(_cache->contains(path))
+        {
+            infoData = _cache->object(path);
+        }
+        else
+        {
+            infoData = new ImageInfoData;
+            if(isFITS(suffix))
+                readFITSHeader(path, *infoData);
+            else if(isXISF(suffix))
+                readXISFHeader(path, *infoData);
+            _cache->insert(path, infoData);
+        }
+        for(auto &record : infoData->fitsHeader)
+            if(record.key == "OBJECT")
+                return record.value;
+
+        return "";
+    }
+    return QFileSystemModel::data(index, role);
+}
+
+QVariant DirFileSystemModel::headerData(int section, Qt::Orientation orientation, int role) const
+{
+    if(orientation == Qt::Horizontal && role == Qt::DisplayRole && section >= QFileSystemModel::columnCount())
+        return "FITS";
+
+    return QFileSystemModel::headerData(section, orientation, role);
+}
+
+bool DirFileSystemModel::hasChildren(const QModelIndex &parent) const
+{
+    if(parent.parent() == _dir)return false;
+
+    return QFileSystemModel::hasChildren(parent);
+}
+
+DirView::DirView(QWidget *parent) : QTreeView(parent)
+{
+    _dirFileSystemModel = new DirFileSystemModel(this);
+#ifdef Q_OS_LINUX
+    _dirFileSystemModel->setRootPath("/");
+#elif defined(Q_OS_WIN64)
+    _dirFileSystemModel->setRootPath("C:/");
+#endif
+    _dirFileSystemModel->setReadOnly(false);
+    setDragEnabled(true);
+    setAcceptDrops(true);
+
+    setModel(_dirFileSystemModel);
+    setSelectionMode(QAbstractItemView::ExtendedSelection);
+
+    connect(this, &QTreeView::doubleClicked, [this](const QModelIndex &index){
+        QFileInfo info = _dirFileSystemModel->fileInfo(index);
+        if(_dirFileSystemModel->isDir(index))
+        {
+            setDir(info.canonicalFilePath());
+        }
+        else if(info.isFile())
+        {
+            if(_openFilter.contains(info.suffix()))
+                emit openFile(info.absoluteFilePath());
+            else
+                QDesktopServices::openUrl(QUrl::fromLocalFile(info.absoluteFilePath()));
+        }
+    });
+}
+
+void DirView::setDir(const QString &path)
+{
+    _dirFileSystemModel->setDir(path);
+    setRootIndex(_dirFileSystemModel->index(path, 0));
+    clearSelection();
+    emit dirChanged(path);
+}
+
+QString DirView::dir() const
+{
+    return _dirFileSystemModel->dir();
+}
+
+void DirView::setOpenFilter(const QSet<QString> &openFilter)
+{
+    _openFilter = openFilter;
+}
diff --git a/src/filemanager.h b/src/filemanager.h
new file mode 100644
index 0000000..709132b
--- /dev/null
+++ b/src/filemanager.h
@@ -0,0 +1,57 @@
+#ifndef FILEMANAGER_H
+#define FILEMANAGER_H
+
+#include <QMainWindow>
+#include <QCache>
+#include <QFileSystemModel>
+#include <QTreeView>
+#include "imageinfodata.h"
+
+namespace Ui {
+class FileManager;
+}
+
+class FileManager : public QMainWindow
+{
+    Q_OBJECT
+public:
+    explicit FileManager(const QSet<QString> &openFilter, QWidget *parent = nullptr);
+    ~FileManager();
+signals:
+    void openFile(const QString &path);
+private:
+    Ui::FileManager *ui;
+};
+
+class DirFileSystemModel : public QFileSystemModel
+{
+    mutable QCache<QString, ImageInfoData> *_cache = nullptr;
+    static QCache<QString, ImageInfoData>* getCacheInstance();
+    QModelIndex _dir;
+public:
+    explicit DirFileSystemModel(QObject *parent = nullptr);
+    void setDir(const QString &path);
+    QString dir() const;
+    Qt::ItemFlags flags(const QModelIndex &index) const override;
+    int columnCount(const QModelIndex &parent) const override;
+    QVariant data(const QModelIndex &index, int role) const override;
+    QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
+    bool hasChildren(const QModelIndex &parent) const override;
+};
+
+class DirView : public QTreeView
+{
+    Q_OBJECT
+    DirFileSystemModel *_dirFileSystemModel = nullptr;
+    QSet<QString> _openFilter;
+public:
+    explicit DirView(QWidget *parent = nullptr);
+    void setDir(const QString &path);
+    QString dir() const;
+    void setOpenFilter(const QSet<QString> &openFilter);
+signals:
+    void dirChanged(const QString &path);
+    void openFile(const QString &path);
+};
+
+#endif // FILEMANAGER_H
diff --git a/src/filemanager.ui b/src/filemanager.ui
new file mode 100644
index 0000000..137be0a
--- /dev/null
+++ b/src/filemanager.ui
@@ -0,0 +1,68 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>FileManager</class>
+ <widget class="QMainWindow" name="FileManager">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>1282</width>
+    <height>858</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>File Manager</string>
+  </property>
+  <widget class="QWidget" name="centralwidget">
+   <layout class="QHBoxLayout" name="horizontalLayout">
+    <item>
+     <layout class="QVBoxLayout" name="verticalLayout">
+      <item>
+       <widget class="QLineEdit" name="leftPath">
+        <property name="readOnly">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="DirView" name="leftTab"/>
+      </item>
+     </layout>
+    </item>
+    <item>
+     <layout class="QVBoxLayout" name="verticalLayout_2">
+      <item>
+       <widget class="QLineEdit" name="rightPath">
+        <property name="readOnly">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="DirView" name="rightTab"/>
+      </item>
+     </layout>
+    </item>
+   </layout>
+  </widget>
+  <widget class="QMenuBar" name="menubar">
+   <property name="geometry">
+    <rect>
+     <x>0</x>
+     <y>0</y>
+     <width>1282</width>
+     <height>23</height>
+    </rect>
+   </property>
+  </widget>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>DirView</class>
+   <extends>QTreeView</extends>
+   <header>filemanager.h</header>
+  </customwidget>
+ </customwidgets>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/filesystemwidget.cpp b/src/filesystemwidget.cpp
index c97b7bd..c7f2b33 100644
--- a/src/filesystemwidget.cpp
+++ b/src/filesystemwidget.cpp
@@ -5,6 +5,7 @@
 #include <QMenu>
 #include <QSettings>
 #include <QHeaderView>
+#include <QMimeDatabase>
 
 FilesystemWidget::FilesystemWidget(QAbstractItemModel *model, QWidget *parent) : QWidget(parent)
   , m_model(model)
@@ -117,6 +118,7 @@ void Filetree::contextMenuEvent(QContextMenuEvent *event)
     {
         setRootIndex(index);
         m_rootDir = m_fileSystemModel->filePath(index);
+        m_fileSystemModel->setRootPath(m_rootDir);
     }
     else if(a == resetRoot)
     {
@@ -127,6 +129,7 @@ void Filetree::contextMenuEvent(QContextMenuEvent *event)
     {
         setRootIndex(rootIndex().parent());
         m_rootDir = m_fileSystemModel->filePath(rootIndex().parent());
+        m_fileSystemModel->setRootPath(m_rootDir);
     }
     else if(a == copy)
     {
diff --git a/src/filesystemwidget.h b/src/filesystemwidget.h
index 6483407..0cdab94 100644
--- a/src/filesystemwidget.h
+++ b/src/filesystemwidget.h
@@ -3,6 +3,7 @@
 
 #include <QWidget>
 #include <QFileSystemModel>
+#include <QIdentityProxyModel>
 #include <QListView>
 #include <QTreeView>
 
diff --git a/src/loadimage.cpp b/src/loadimage.cpp
index d489753..3ddfacc 100644
--- a/src/loadimage.cpp
+++ b/src/loadimage.cpp
@@ -409,18 +409,19 @@ bool loadImage(const QString &path, ImageInfoData &info, std::shared_ptr<RawImag
 {
     bool ret = false;
     QElapsedTimer timer;
+    QFileInfo fileInfo(path);
     timer.start();
     if(path.endsWith(".CR2", Qt::CaseInsensitive) || path.endsWith(".CR3", Qt::CaseInsensitive) || path.endsWith(".NEF", Qt::CaseInsensitive) || path.endsWith(".DNG", Qt::CaseInsensitive))
     {
         ret = loadRAW(path, info, rawImage);
         qDebug() << "LoadRAW" << timer.elapsed();
     }
-    else if(path.endsWith(".FIT", Qt::CaseInsensitive) || path.endsWith(".FITS", Qt::CaseInsensitive) || path.endsWith(".FZ", Qt::CaseInsensitive) || path.endsWith(".FTS", Qt::CaseInsensitive))
+    else if(isFITS(fileInfo.suffix()))
     {
         ret = loadFITS(path, info, rawImage, planar, index);
         qDebug() << "LoadFITS" << timer.elapsed();
     }
-    else if(path.endsWith(".XISF", Qt::CaseInsensitive))
+    else if(isXISF(fileInfo.suffix()))
     {
         ret = loadXISF(path, info, rawImage, planar, index);
         qDebug() << "LoadXISF" << timer.elapsed();
@@ -444,3 +445,13 @@ bool loadImage(const QString &path, ImageInfoData &info, std::shared_ptr<RawImag
     }
     return ret;
 }
+
+bool isFITS(const QString &suffix)
+{
+    return suffix.compare("fits", Qt::CaseInsensitive) == 0 || suffix.compare("fit", Qt::CaseInsensitive) == 0 || suffix.compare("fts", Qt::CaseInsensitive) == 0 || suffix.compare("fz", Qt::CaseInsensitive) == 0;
+}
+
+bool isXISF(const QString &suffix)
+{
+    return suffix.compare("xisf", Qt::CaseInsensitive) == 0;
+}
diff --git a/src/loadimage.h b/src/loadimage.h
index 74cecc1..793c408 100644
--- a/src/loadimage.h
+++ b/src/loadimage.h
@@ -10,5 +10,7 @@ QString makeUNCPath(const QString &path);
 bool readFITSHeader(const QString &path, ImageInfoData &info);
 bool readXISFHeader(const QString &path, ImageInfoData &info);
 bool loadImage(const QString &path, ImageInfoData &info, std::shared_ptr<RawImage> &rawImage, int index, bool planar = false);
+bool isFITS(const QString &suffix);
+bool isXISF(const QString &suffix);
 
 #endif // LOADIMAGE_H
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index 0b1caed..0cc9a34 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -29,6 +29,7 @@
 #include "settingsdialog.h"
 #include "histogram.h"
 #include "batchprocessing.h"
+#include "filemanager.h"
 
 #ifdef __linux__
 #include <sys/ioctl.h>
@@ -66,6 +67,7 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
     _openFilter.append(tr(";;All files (*)"));
     nameFilter.append({"fit", "fits", "fts", "fz", "xisf", "cr2", "cr3", "nef", "dng"});
     QImageReader::setAllocationLimit(0);
+    _openSuffix = {nameFilter.constBegin(), nameFilter.constEnd()};
 
     m_info = new ImageInfo(this);
     QDockWidget *infoDock = new QDockWidget(tr("Image info"), this);
@@ -176,6 +178,7 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
     fileMenu->addAction(tr("Open directory recursively"), this, &MainWindow::loadDir);
     QAction *saveAs = fileMenu->addAction(tr("Save as"), QKeySequence::Save, this, &MainWindow::saveAs);
     fileMenu->addSeparator();
+    fileMenu->addAction(tr("File manager"), this, &MainWindow::openFileManager);
     fileMenu->addAction(tr("Copy marked files"), Qt::Key_F5, this, &MainWindow::copyMarked);
     fileMenu->addAction(tr("Move marked files"), Qt::Key_F6, this, &MainWindow::moveMarked);
     fileMenu->addAction(tr("Move marked files to trash"), QKeySequence::Delete, this, &MainWindow::deleteMarked);
@@ -808,6 +811,13 @@ void MainWindow::checkNewVersion()
     });
 }
 
+void MainWindow::openFileManager()
+{
+    FileManager *filemanager = new FileManager(_openSuffix);
+    connect(filemanager, &FileManager::openFile, this, static_cast<void (MainWindow::*)(const QString&)>(&MainWindow::loadFile));
+    filemanager->show();
+}
+
 void MainWindow::updateWindowTitle()
 {
     ImagePtr ptr = m_ringList->currentImage();
diff --git a/src/mainwindow.h b/src/mainwindow.h
index d091c16..feb565d 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -30,6 +30,7 @@ class MainWindow : public QMainWindow
     bool _maximized;
     QString _openFilter;
     QString _saveFilter;
+    QSet<QString> _openSuffix;
 public:
     MainWindow(QWidget *parent = 0);
     ~MainWindow() override;
@@ -67,6 +68,7 @@ public slots:
     void showSettingsDialog();
     void exportCSV();
     void checkNewVersion();
+    void openFileManager();
 };
 
 #endif // MAINWINDOW_H
diff --git a/src/scriptengine.cpp b/src/scriptengine.cpp
index 878116a..61be4a9 100644
--- a/src/scriptengine.cpp
+++ b/src/scriptengine.cpp
@@ -455,11 +455,11 @@ void File::loadFitsKeywords()
     {
         _fitsKeywordsLoaded = true;
         ImageInfoData info;
-        if(suffix().toLower() == "xisf")
+        if(isXISF(suffix()))
         {
             readXISFHeader(_path, info);
         }
-        else if(suffix().toLower() == "fits" || suffix().toLower() == "fit" || suffix().toLower() == "fz")
+        else if(isFITS(suffix()))
         {
             readFITSHeader(_path, info);
         }