Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: F tables - "F-Tafel"
    From: Hewitt Schlereth
    Date: 2013 Jan 30, 13:23 -0800

    Thanks, Dave. Too pricey for me. I'll just figure it's a lot like Dreisenstok 
    and let it go at that.  Hewitt
    Sent from my iPad
    On Jan 30, 2013, at 1:05 PM, "Dave Walden"  wrote:
    > F-tafel, tafel zur vereinfachten berechnung von höhenstandlinien. Im auftage 
    des Oberkommandos der Kriegsmarine herausgegeben von der Deutschen seewarte.
    > Corporate Author:    Deutsche Seewarte.
    > Language(s):    German
    > Published:    Hamburg, 1941.
    > Edition:    3. aufl.
    > Subjects:    Azimuth.
    > Note:    In upper right corner of t.-p.: 2154.
    > Physical Description:    xxiii, 88 p. 30 cm.
    > Original Format:    Book
    > Original Classification Number:    VK 563 .H19 1941
    > Locate a Print Version:    Find in a library
    > *******************
    > F-Tafel. Tafel zur vereinfachten Berechnung von Höhenstandlinien. Im 
    Auftrage des Oberkommandos der Kriegsmarine herausgegeben von der Deutschen 
    >    * Bookseller: Versandantiquariat Lutz Bäsler (Bad Homburg, Hess, Germany)
    >    * Bookseller Rating: 3-star rating
    >    * Quantity Available: 1
    > Add to basket
    > Price: £ 42.35 
    > ******************************
    > 29S[U].—Hamburg, Deutsche Seewarte, publication no. 2154, F-Tafel.
    > Tafel zur vereinfachten Berechnung von Höhenstandlinien. 3 Auflage.
    > Hamburg, August, 1941. xxiii, 88 p. 19.6 X 29.2 cm. In the third
    > edition there were extensions and corrections of the introductory material,
    > and of 8 of the 11 tables.
    > The method and principal table of this volume are similar in many respects to those of
    > H. O. 208 (Dreisonstok, see MTAC, v. 1, p. 79f). The astronomical triangle is divided
    > into two right spherical triangles by a perpendicular from the zenith upon the hour circle
    > of the star; U is the co-declination of the foot of the perpendicular, and V is log cos B,
    > where B is the angle subtended at the zenith by U. By Napier's rules,
    > tan U = cos I cot L
    > and
    > sin B = sin / cos L,
    > where /, L, and d are the local hour angle, latitude and declination respectively. By applying
    > another of Napier's rules to the right triangle of which the star is one vertex, the altitude,
    > h, may be found by
    > sin h = cos B sin (d + U)
    > or
    > log sin h = V + log sin (d + U).
    > For the determination of azimuth, Z, two more auxiliary quantities are introduced,
    > P which is the great circle distance from the star to the east- or west-point of the horizon,
    > and Gr. 4 which is the declination of the intersection of the hour circle of the star with the
    > prime vertical. Thus, sin t cosd ■>c osP and sin Z = cos P sec h. Also, tan Gr. S = tan L cos t.
    > In Table F I, with vertical argument, latitude 0(1°)70°, and horizontal argument,
    > local hour angle 0(4m)6h, three values per page, there are tabulated four quantities, U to
    > the nearest O'.l, V to 5D, Gr. 5 and P, each to the nearest 0?1. In the second part of
    > Table F I, the vertical argument is latitude, 70°(1°)90°, and the horizontal argument is
    > local hour angle 0(4m)6h, nine values per page, three in each horizontal section.
    > At ths bottom of the vertical columns in Table F I are azimuths; entering the left
    > hand column with altitude as argument, and moving across the pages horizontally until one
    > finds under P, the value already copied out, one can drop to the bottom of the column
    > and read off the azimuth angle. Since the tabulated values of the azimuth angle go up to
    > 90° only, it is necessary to have another device to determine the quadrant. When the
    > hour angle is greater than 6b, the azimuth is measured from the elevated pole; when the
    > local hour angle is less than 6h and L and d are of opposite name, the azimuth is measured
    > from the depressed pole. If the local hour angle is less than 6h and L and d are of the same
    > name, the azimuth is measured from the elevated or depressed pole according as the declination
    > is greater or less than the quantity Gr. a.
    > In case the altitude is great, or the azimuth near 90°, the value of the azimuth may be
    > poorly determined by the use of Table F I. In such a case, it will be noted that the value
    > of P lies below a dotted line running across the page. One must then use instead Table
    > F XI, which gives P to the nearest minute of arc and the variation in P corresponding to
    > 1' change in d or h.
    > Table F II is a table of log sin x, x = [0(0'-1)6°(1')90°; 5D], with generous tables of
    > proportional parts.
    > Tables F DI and F IV represent the principal advantages this volume possesses over
    > other similar tables; they permit one to determine the corrections (to the nearest 0!1) to
    > the computed altitude corresponding to slight changes in time (up to 2m by 10* steps) or latitude
    > (up to 30' by 1' steps) respectively. In both cases, one can interpolate very easily by a
    > shift of the decimal point. Table F III is a well-designed triple-entry table occupying only
    > five pages; one starts down the column at the left headed by the value nearest the assumed
    > latitude, stops at the value nearest the computed azimuth and moves to the right to the
    > column headed by the number of seconds change in time. Table F IV is a small doubleentry
    > table on a single page; the vertical argument is azimuth 0(5°)20°(2°)90°, and the
    > horizontal argument is change in latitude, l'(l')10'(10')30'. These two tables allow one to
    > work either with an assumed position or with a dead reckoning position.
    > Table F V is for changing time into angular measure and conversely. Table F VI gives
    > the corrections for refraction, semi-diameter and parallax to be applied to the altitude
    > (3°-90°) of the lower- or upper-limb of the moon; there is a supplementary table for height
    > of eye. Table F VU gives the combined correction for refraction and height of eye (0-30
    > meters) to be applied to the altitudes (3°-90°) of fixed stars or planets. Table F VIH yields
    > the correction for refraction, semi-diameter and height of eye (0-30 meters) to be applied
    > to altitudes (3°-90°) of the sun's lower limb; there are also two auxiliary tables to provide
    > corrections to the altitudes to take care of the varying semi-diameter of the sun through the
    > year, and for the case where the sun's upper limb was observed. The latter takes only a
    > very small amount of space and would seem to be quite worthwhile. Tables F IX and F X
    > provide similar corrections for use with the bubble sextant.
    > The tables are well printed on a good grade of paper. In a number of cases, the rules
    > needed to make decisions as to quadrants, etc. are printed on each page. As for the accuracy
    > of the tabulated values, only a few rounding off errors of a unit in the last place were
    > discovered in a brief examination.
    > Charles H. Smiley
    > Brown University
    > ----------------------------------------------------------------
    > NavList message boards and member settings: www.fer3.com/NavList
    > Members may optionally receive posts by email.
    > To cancel email delivery, send a message to NoMail[at]fer3.com
    > ----------------------------------------------------------------
    > View and reply to this message: http://fer3.com/arc/m2.aspx?i=122177

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site