Geographic Projections

The structure of the succeeding words of the following geographic projections are listed here:

If the type is LAMB, this is the structure of the succeeding words:

Word	Description
2	image line of the North Pole
3	image element of the North Pole
4	standard latitude 1, DDDMMSS
5	standard latitude 2, DDDMMSS
6	spacing at standard latitude, meters
7	normal longitude, DDDMMSS
8	radius of the planet, meters
9	eccentricity of the planet, x1000000
10	coordinate type, ≥ 0 planetodetic, < 0 planetocentric
11	longitude convention, ≥ 0 west positive, < 0 west negative
12-120	reserved
121-128	memo entry; up to 32 characters of comments

If the type is MERC, this is the structure of the succeeding words:

Word	Description
2	image line of the equator
3	image element of the normal longitude
4	standard latitude, DDDMMSS; usually zero
5	spacing at standard latitude, meters
6	normal longitude, DDDMMSS
7	radius of the planet, meters
8	eccentricity of the planet, x1000000
9	coordinate type, ≥ 0 planetodetic, < 0 planetocentric
10	longitude convention, ≥ 0 west positive, < 0 west negative
11-120	reserved
121-128	memo entry; up to 32 characters of comments

If the type is 'PS ' (four characters), this is the structure of the succeeding words:

Word	Description
2	image line of the North Pole
3	image element of the North Pole
4	standard latitude, DDDMMSS
5	spacing at standard latitude, meters
6	normal longitude, DDDMMSS
7	radius of the planet, meters
8	eccentricity of the planet, x1000000
9	coordinate type, ≥ 0 planetodetic, < 0 planetocentric
10	longitude convention, ≥ 0 west positive, < 0 west negative
11-120	reserved
121-128	memo entry; up to 32 characters of comments

If the type is RADR, this is the structure of the succeeding words:

Word	Description
2	row (image coordinates) of the radar site
3	column (image coordinates) of the radar site
4	latitude of the radar site, DDDMMSS
5	longitude of the radar site, DDDMMSS
6	pixel resolution, meters
7	rotation of north from vertical, degrees x1000
8	if present, same as 6, but only for longitude direction

If the type is RECT, this is the structure of the succeeding words:

Word	Description
2	a particular image row number
3	latitude corresponding to word 2, degrees x10000
4	a particular image column number
5	longitude corresponding to word 4, degrees x10000
6	latitude degrees/image line, degrees x10000
7	longitude degrees/image line, degrees x10000
8	radius of the planet, meters
9	eccentricity of the planet, x1000000
10	coordinate type, ≥ 0 planetodetic, < 0 planetocentric
11	longitude convention, ≥ 0 west positive, < 0 west negative

If the type is LALO, this is the structure of the succeeding words:

Word	Description
2	SERV (indicates that the nav is coming from a server)
3-65	reserved
66	number of rows in LALO array
67	number of elements in LALO array
68	minimum latitude as a floating point number (in real*4 format) moved to the integer space
69	minimum longitude as a floating point number (in real*4 format) moved to the integer space
70	maximum latitude as a floating point number (in real*4 format) moved to the integer space
71	maximum longitude as a floating point number (in real*4 format) moved to the integer space
72	resolution of line lalo, 1 means there is latitude for every image line
73	resolution of element lalo, 1 means there is longitude for every image element
74	512 (size of NAV array)
75	word 74 + ((word 66)(word 67)(4))
76	line number in image coordinates of top line
77	element number in image coordinates of leftmost element
78	total size of LALO block
79	24 (size of latitude header)
80	offset in AUX to longitudes: word 79 + ((word 66)(word 67)(4)) + 28
81	offset in directory block to latitude block: 768 + word 79 + cal_length
82	offset in directory block to longitude block: word 81 + ((word 66)(word 67)(4)) + 28
83-128	reserved