NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: CP-300/U USAF Star Finder
From: Brad Morris
Date: 2019 Jun 26, 15:31 -0400
From: Brad Morris
Date: 2019 Jun 26, 15:31 -0400
Hi Tony
The 2102D and its variant CP-300/U both use the same azimuthal equidistant overlays. For a view of how the shape changes, for any combination of hemisphere, latitude and overlay, take a look at my electronic 2102E. So, you can see southern latitude stars from high northern latitude overlays, with crazy combinations to any latitude.
Just please do not use it for actual navigation. It was a toy I developed to permit my understanding of the internals of the device. Further, I am not convinced that one is the "final" version.
To draw on the device, you would use a very sharp #2 pencil, which can be erased from the white plastic.
Please be advised that the use of the device with sun and moon can be done, but isn't worth the effort in my opinion. You really aren't going to need a lot of help for the sun or moon. They kind of distinguish themselves. So it is the planets alone that you may wish to plot.
Brad
On Wed, Jun 26, 2019, 2:17 PM Tony Oz <NoReply_TonyOz@fer3.com> wrote:
Dear Brad, thanks for the comment.
Slowly-slowly, meditating over CP-300/U starfinder, I begin to understand why those scales are that way. (Because it is not a planisphere, we are supposed to look at it as if from the "outside" of the celestial sphere.) Most difficult part (for me) is imagining near-Equator southern hemisphere pictures.
Still can not comprehend the purpose of the "fat" black arrow near the bend of the cursor bracket...
Now I'm hacking a slotted ruler for placing Sun/Moon/planets. The scale is 1° per millimeter. What type of marker would you recommend for doing such marks? I'm afraid usual pencils will leave difficult to remove graphite dirt.
Regards,
Tony60°N 30°E
