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[[underlined]] To Compute Precession [[/underlined]]

[[underlined]] Declination [[/underlined]]

Use tables in the margin of the Cape Photographic Durchmusterung, Volume III, which give the total precession for 25 years. If precession for 45 years is desired, multiply the given quantity by 2 and subtract 1/10 of the result.

[[underlined]] Right Ascension [[/underlined]]

Stars [[underlined]] south [[/underlined]] of the Equator

(a) If south of - [[strikethrough]] 52 [[/strikethrough]] 19 degrees, use the precession tables in the margin of the Cape Photographic Durchmusterung, Volume III.

(b) If between the equator and - [[strikethrough]] 52 [[/strikethrough]] 19 degrees, use Table I in the Zone Catalogue, Volume II ^[[7 or 8]]. To find precession for 25 years, divide the annual precession by 4 and multiply the result by 100. To find precession for 45 years, divide the annual precession by 2, multiply by 100 and subtract 1/10 of the result.

Stars [[underlined]] north [[/underlined]] pf the equator
 Change the right ascension by 12 hours and proceed as for stars south of the equator.

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Correction to first scale

I, B, and Ma Plates  +0.2 scale from I 32811
A, X, H.C.   "[[ditto for Plates]]  -0.3 " "[[ditto for scale from]] C 15350

AC, AM Plates with usual aperture, Scale AC 8858
   Scale I corrections = -0.2
         2 "[[ditto for corrections]] = -0.4
         3 "[[ditto for corrections]] = 0.0

AC, AM Plates with reduced aperture
AI Plates   Scale 8796
   Scale I corr. 0.0
   "[[ditto for Scale]] 2 "[[ditto for corr.]] -0.3
   "[[ditto for Scale]] 3 "[[ditto for corr.]] 0.0