|
|
Subject: Re: LOP's
From: Rick Emerson (rick@XXX.XXX)
Date: Thu Jun 24 1999 - 00:38:20 EDT
Robert Owens writes:
> >>All LOP's of a celestial nature need an arrow at each end. This is
> >>perhaps not so important with say a single sun observation but when
> >>it comes down to a multi star/planet set of observations (as many as
> >>six or maybe more) you need to distinguish the azimuth lines from
> >>the Position lines by placing the arrows.What a clutter we have if we
> Snip---
>
>
> Bowditch and the Power Squadron teach that construction lines (azimuth
> lines, and Drift and Set lines,etc.) should be dashed lines which
> differentiate at a glance which are the LOP's and which are not without
> having to draw arrows. If arrows are taught somewhere I would really like to
> know where so I could further my education.
IMHO, "construction lines" are like scaffolding on a building; one
takes the scaffolding down when the building's done. Either circular
LOP's (from ranges) or straight LOP's (from bearings) should be
labeled, allowing recreating the plot, if need be, from notes and
comparison with the existing plotting sheet. Keeping lots of dashed
lines, as I've said before, can make for a cluttered sheet.
On the matter of arrows, it's really very simple. An original LOP
receives an arrow at each end, thus: <----------> Advance the line
and it gets double arrows, thus: <<---------->> Mark the original
line with time, date, and (for celestial work) symbol and the advanced
line with the original data and time and date for the advanced line.
Rick
S/V One With The Wind, Baba 35
|