The Caldwell Catalog Builder is a free desktop app for planning and logging your sessions across all 109 objects in the Caldwell catalog — the list Patrick Moore put together to cover the bright deep-sky objects Messier's catalog left out. Most of the list sits in the northern sky and is well within reach from across North America and Europe, with a handful of southern objects needing more southerly latitudes.
It lays the whole catalog out as one chart with a toolbar for adding photos, exporting the finished chart as an image, editing the title, and opening your library folder directly. A live counter in the corner (like the 11/109 shown below) tracks how many objects you've filled in.
For each object you can log your exposure time, sub-length and count, gain, and the equipment you used, along with your own notes, so you build up a complete record of what you've imaged and how you shot it.
Like its companions, it's a native desktop application that runs entirely offline on your own machine — your logs never leave your computer. Available for Windows and macOS (both Apple Silicon and Intel). It's the direct companion to the Messier and Sharpless Catalog Builders, so if you're working through more than one list, the workflow stays identical across all three.
