A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brad Morris
Date: 2019 Feb 13, 11:25 -0800
Thank you for clarifying where you get EoT and Declination from.
I note that, for 11 Nov, you state the declination to be 17°. This is one digit less than the Dunlap Sunrise Sunset Computer (DSSC). The DSSC provides 17.4° for 11 November. Perhaps you could provide further resolution on the reading scale for the reverse graph.
The DSSC also provides the time of meridian passage of the sun on the M scale. For 11 Nov, it provides 1136 as the time, for that all important LAT noon latitude observation. You may wish to include that.
There is one other suggestion I might make. For the DSSC, the circular scale on the base is NOT a complete 24 hours. The top half goes from 0300 to 0900. The bottom half goes from 1500 to 2100. This expands the resolution of the latitude curve, permitting a tic mark every 0002 minutes of time.
Did you make an actual device? Or is this a virtual (computer screen) device? Watch out for centering errors of the scales, base and pointers. This device is fairly sensitive to such issues.
I think you are doing famously. These comments are intended to be a helpful critique, not an ad hominem attack. Hopefully, you see it that way!!