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Bahtinov Mask Generator
Looking for the original online Bahtinov mask generator? That generator is no more, but has been completely rewritten as a Windows application. To download the latest version, click “DOWNLOAD” above. For more information, click “GitHub project” at the bottom of the page.
The Windows version not only creates Bahtinov masks, it also produces Tri-Bahtinov masks, Hartmann masks, Scheiner disks, Carey masks, Couder masks, and more.
If you don’t have (or hate) Windows, or just can’t stand to download another piece of free software, check out Satoru Takagi’s online generator here.
Shutter count utilities
I no longer develop or maintain these utilities (EOSInfo, 40DShutterCount), as Canon made it far too difficult to get access to their DSLR SDK.