diff --git a/include/aare/JungfrauDataFile.hpp b/include/aare/JungfrauDataFile.hpp
index f395a6b..026cc66 100644
--- a/include/aare/JungfrauDataFile.hpp
+++ b/include/aare/JungfrauDataFile.hpp
@@ -13,6 +13,12 @@ class JungfrauDataFile {
     size_t m_rows{};
     size_t m_cols{};
     size_t m_total_frames{};
+    size_t m_first_frame_index{};
+
+    std::vector<size_t> m_frames_in_file{};
+
+    std::filesystem::path m_base_path;
+    std::string m_base_name;
 
     //Data sizes to guess the frame size
     using value_type = uint16_t;
@@ -21,8 +27,12 @@ class JungfrauDataFile {
     static constexpr size_t half_data_size = header_size + sizeof(value_type) * 256 * 1024;
     static constexpr size_t chip_data_size = header_size + sizeof(value_type) * 256 * 256; 
 
+    static constexpr size_t n_digits_in_file_index = 6;
+
   public:
     JungfrauDataFile(const std::filesystem::path &fname);
+
+    std::string base_name() const; //!< get the base name of the file (without path and extension)
     size_t bytes_per_frame() const;           
     size_t pixels_per_frame() const;    
     size_t bytes_per_pixel() const;  
@@ -36,6 +46,7 @@ class JungfrauDataFile {
     void read_into(std::byte *image_buf, JungfrauDataHeader *header);
 
     static size_t guess_frame_size(const std::filesystem::path &fname);
+    static std::filesystem::path get_frame_path(const std::filesystem::path &path, const std::string& base_name, size_t frame_index);
 };
 
 } // namespace aare
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diff --git a/python/src/jungfrau_data_file.hpp b/python/src/jungfrau_data_file.hpp
index f27241e..6160baa 100644
--- a/python/src/jungfrau_data_file.hpp
+++ b/python/src/jungfrau_data_file.hpp
@@ -23,7 +23,14 @@ void define_jungfrau_data_file_io_bindings(py::module &m) {
                  return JungfrauDataFile::guess_frame_size(fname);
              })
         .def_property_readonly("rows", &JungfrauDataFile::rows)
-        .def_property_readonly("cols", &JungfrauDataFile::cols);
+        .def_property_readonly("cols", &JungfrauDataFile::cols)
+        .def_property_readonly("base_name", &JungfrauDataFile::base_name)
+        .def("get_frame_path",
+             [](const std::filesystem::path &path, const std::string &base_name,
+                size_t frame_index) {
+                 return JungfrauDataFile::get_frame_path(path, base_name,
+                                                        frame_index);
+             });
         // .def("read_frame",
         //      [](RawFile &self) {
         //          py::array image;
diff --git a/src/JungfrauDataFile.cpp b/src/JungfrauDataFile.cpp
index e25873d..08bf136 100644
--- a/src/JungfrauDataFile.cpp
+++ b/src/JungfrauDataFile.cpp
@@ -1,9 +1,13 @@
 #include "aare/JungfrauDataFile.hpp"
 #include "aare/defs.hpp"
 
+#include <fmt/format.h>
+
 namespace aare{
 
 JungfrauDataFile::JungfrauDataFile(const std::filesystem::path& fname){
+
+    //setup geometry
     auto frame_size = guess_frame_size(fname);    
     if (frame_size == module_data_size) {
         m_rows = 512;
@@ -17,9 +21,32 @@ JungfrauDataFile::JungfrauDataFile(const std::filesystem::path& fname){
     } else {
         throw std::runtime_error(LOCATION + "Cannot guess frame size: file size is not a multiple of any known frame size");
     }      
+
+    m_base_path = fname.parent_path();
+    m_base_name = fname.stem();
+
+    //need to know the first 
+
+    //remove digits
+    while(std::isdigit(m_base_name.back())){
+        m_base_name.pop_back();
+    }
+
+    //find how many files we have 
+    // size_t frame_index = 0;
+    // while (std::filesystem::exists(get_frame_path(m_base_path, m_base_name, frame_index))) {
+    //     auto n_frames =
+    //     m_frames_in_file.push_back(n_frames);
+    //     ++frame_index;
+    // }
+
 }
 
 
+std::string JungfrauDataFile::base_name() const {
+    return m_base_name;
+}
+
 size_t JungfrauDataFile::bytes_per_frame() const{
     return m_rows * m_cols * bytes_per_pixel();
 }          
@@ -67,9 +94,11 @@ size_t JungfrauDataFile::guess_frame_size(const std::filesystem::path& fname)  {
     } else {
         throw std::runtime_error(LOCATION + "Cannot guess frame size: file size is not a multiple of any known frame size");
     }
-
-
 }
 
+std::filesystem::path JungfrauDataFile::get_frame_path(const std::filesystem::path& path, const std::string& base_name, size_t frame_index) {
+    auto fname = fmt::format("{}{:0{}}.dat", base_name, frame_index, n_digits_in_file_index);
+    return path / fname;
+}
 
 } // namespace aare
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