diff --git a/core/include/aare/Frame.hpp b/core/include/aare/Frame.hpp
index c48a4b4..8ee386d 100644
--- a/core/include/aare/Frame.hpp
+++ b/core/include/aare/Frame.hpp
@@ -26,22 +26,23 @@ class Frame {
     Frame(ssize_t rows, ssize_t cols, ssize_t m_bitdepth);
     Frame(std::byte *fp, ssize_t rows, ssize_t cols, ssize_t m_bitdepth);
     std::byte *get(int row, int col);
-    // template <typename T> void set(int row, int col, T data);
+
+    
+    //TODO! can we, or even want to remove the template?
     template <typename T>
     void set(int row, int col, T data) {
         assert(sizeof(T) == m_bitdepth/8);
         if (row < 0 || row >= m_rows || col < 0 || col >= m_cols) {
-            std::cerr << "Invalid row or column index" << std::endl;
-    return;
-  }
-  std::memcpy(m_data+(row*m_cols + col)*(m_bitdepth/8), &data, m_bitdepth/8);
-}
+            throw std::out_of_range("Invalid row or column index");
+        }
+        std::memcpy(m_data+(row*m_cols + col)*(m_bitdepth/8), &data, m_bitdepth/8);
+    }
 
     ssize_t rows() const { return m_rows; }
     ssize_t cols() const { return m_cols; }
     ssize_t bitdepth() const { return m_bitdepth; }
     ssize_t size() const { return m_rows * m_cols * m_bitdepth / 8; }
-    std::byte *_get_data() { return m_data; }
+    std::byte *data() { return m_data; }
     
     Frame &operator=(Frame &other) {
         m_rows = other.rows();
diff --git a/file_io/src/NumpyFile.cpp b/file_io/src/NumpyFile.cpp
index e153b5f..ab7e602 100644
--- a/file_io/src/NumpyFile.cpp
+++ b/file_io/src/NumpyFile.cpp
@@ -38,14 +38,14 @@ void NumpyFile::write(Frame &frame) {
         throw std::runtime_error("File not open for writing");
     }
     fseek(fp, 0, SEEK_END);
-    fwrite(frame._get_data(), frame.size(), 1, fp);
+    fwrite(frame.data(), frame.size(), 1, fp);
 }
 
 
 
 Frame NumpyFile::get_frame(size_t frame_number) {
     Frame frame(m_header.shape[1], m_header.shape[2], m_header.dtype.bitdepth());
-    get_frame_into(frame_number, frame._get_data());
+    get_frame_into(frame_number, frame.data());
     return frame;
 }
 void NumpyFile::get_frame_into(size_t frame_number, std::byte *image_buf) {
diff --git a/file_io/src/RawFile.cpp b/file_io/src/RawFile.cpp
index e3e52d4..0fd23ce 100644
--- a/file_io/src/RawFile.cpp
+++ b/file_io/src/RawFile.cpp
@@ -5,7 +5,7 @@ namespace aare{
 
 Frame RawFile::get_frame(size_t frame_number) {
     auto f = Frame(this->m_rows, this->m_cols, this->m_bitdepth);
-    std::byte *frame_buffer = f._get_data();
+    std::byte *frame_buffer = f.data();
     get_frame_into(frame_number, frame_buffer);
     return f;
 }