352
June 2020
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
four bases measured in the 1880s by the French; they were
near Sontay, at Than-Hoa, south of Haïphong, and near Baria.
Grand Mirador de Do-Son was observed in April, 1887,
and was a local datum such that Φ
o
= 20° 42´ 24.9˝ N and Λ
o
= 106° 46´ 36.15˝ East of Greenwich. The defining azimuth
was α
o
= 191° 33´ 22˝. In 1929, the coordinates were updated
to Φ
o
= 20° 42´ 24.34˝ N and Λ
o
= 106° 46´ 29.28˝ E, and in
1932 A. Gougenheim finally changed the coordinates of Doson
to Φ
o
= 20° 42´ 24.337˝ N and Λ
o
= 106° 46´ 29.2282˝ E.
Another grid was defined as Haïphong, the west gable
of the observatory pagoda: Φ
o
= 20° 51´ 44.3˝ N and Λ
o
= 106° 40´ 43.95˝ E. Nearby, the derivative Hanoi system
at the “tour de la citadelle,” the tower of the standard, had
coordinates of
j
o
= 21° 01´ 58˝ N and
l
o
= 103° 29´ 52.2˝ E, and
was used for some French surveys, but it was based on the
Haïphong System because its coordinates are x = 99,618.0 m
W. and y = 34,531.0 m N. Furthermore, the derivative Tour de
la citadelle de Nam Dinh had coordinates of
j
o
= 20° 25´ 30.4˝
N and
l
o
= 103° 49´ 50.0˝ E, and was used for some French
surveys, but was based on the Haïphong System because its
coordinates are x = 65,292.8 m W. and y = 32,917.5 m S. Note
that all the azimuthal grids used by the French in Vietnam
were quadrant-based; no false origins were used.
The Hon-Matt Grid based on the Hatt Azimuthal projection
was established in 1877, and is near Vinh on the Ca River.
The coordinates of the origin are
j
o
= 18° 47´ 40˝ N and
l
o
= 105° 55´ 58.95˝ E. In 1924, the Hon-Nieu Grid was used
where
j
o
= 18° 48´ 10.183˝ N and
l
o
= 105° 46´ 33.799˝ E.
It was also used in 1932 for additional French hydrographic
surveys. The old Cape Saint-Jacques Light-house (phare)
hydrographic survey was based on
j
o
= 10° 19´ 33.220˝ N and
l
o
= 104° 44´ 32.663˝ E.
The Bay of Tourane (now Da Nang) Grid was established in
1907 by Cot, where
j
o
= 16° 11´ 01.44˝ Nand
l
o
= 108° 06´ 17.61˝
E; the pillar was listed at Nui-Hoï. The defining azimuth from
Nui-Hoï to Tien-Cha is α
o
= 110° 33´ 32.2˝.
In 1913, a number of new hydrographic survey grids were
established, including the Cathedral of Saïgon, where:
j
o
= 10° 46´ 44.180˝ N and
l
o
= 104° 21´ 25.803˝ East of Paris,
as compared with the Old Observatory of Saïgon where
j
o
= 10° 46´ 42.78˝ N and
l
o
= 104° 21´ 31.29˝ East of Paris.
(Note that Paris is 2° 20´ 13.95˝ East of Greenwich.) The
Bay of Natrang was surveyed with a Hatt Grid in 1913, and
the origin of the coordinates was at Signal Honheo where
j
o
= 12° 24´ 13.11˝ N and
l
o
= 106° 56´ 00.14˝ East of Paris.
By 1914, a Hatt Azimuthal Grid was observed and
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certification
ASPRS congratulates these recently Certified and Re-certified individuals:
CERTIFIEDMAPPING SCIENTIST UAS
Hayes Wilkinson, Certification #UAS033
Effective May 5, 2020, expires May 5, 2025
RECERTIFIEDMAPPING SCIENTISTS GIS/LIS
Timothy Thomas, Certification #R174GS
Effective February 2, 2020, expires February 2, 2025
John Bender, Certification #R211GS
Effective April 1, 2020, expires April 1, 2025
RECERTIFIEDMAPPING SCIENTIST REMOTE SENSING
Jonathan Ellinger, Certification #R224RS
Effective December 15, 2019, expires December 15, 2024
RECERTIFIED PHOTOGRAMMETRISTS
Michael B. Shillenn, Certification #R1027
Effective March 18, 2020, expires March 18, 2025
Sean Maxwell, Certification #R1066
Effective January 11, 2020, expires January 11, 2025
James “Chip” Campbell, Certification #R1443
Effective March 14, 2020, expires March 14, 2025
Zachary DiCicco, Certification #R1581
Effective March 19, 2020, expires March 19, 2025
Todd Andrews, Certification #R1471
Effective December 15, 2019, expires December 15, 2024
Brad W. Marz, Certification #R1448
Effective June 28, 2020, expires June 28, 2025
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