You can make the curve window as large as you want to assist with mouse precision.
Or you can manually or automatically edit the text file of the curve presets: ~.gimp-2.8\tool-options\gimp-curves-tool.settings
You can make the curve window as large as you want to assist with mouse precision.
Or you can manually or automatically edit the text file of the curve presets: ~.gimp-2.8\tool-options\gimp-curves-tool.settings