A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Greg Rudzinski
Date: 2018 Jun 30, 14:17 -0700
Calibration solution for #8 Sun gap DSLR image and #8 center Sun DSLR image.
Sun UT 00:18:51 6/26/2018 assumed Lat. 34° 9.8' N Lon. 119° 13.8' W
Hc 33° 6.3'
refr. + 1.5'
dip + 2.6'
S.D. - 15.7'
gap - 22.5'
Hs 32° 32.2' (calibration using gap image)
Sun UT 00:22:01 6/26/2018
Hc 32° 27.4'
refr. + 1.6'
Hs 32° 31.6' (calibration using center Sun image)
Looks like I should update the calibration card to 32° 31' from 32° 30'
The attached image shows the complete set of prototype cocooned CB's covering an altitude range from 8° to 89° 28' if bright images are included . The very high altitude CB was hard to make and just barely works on a 35 mm lens so I do not recommend going to the limit here. The double polarizer is a worth while add so that bright Sun images can be used. During twilight the bright Moon images can be used without filtering. Night time Moon observations could also be imaged if the horizon is illuminated enough.