improper entry of the height of the CRAB prism cluster into the Zeiss, errors 

 due to the incorrect targeting of the prism cluster, or points which were 

 unaccountably, but obviously, wrong. 



38. The data were also corrected for the angle of tilt of the CRAB. The 

 CRAB operator measures the two orthogonal angles on the main axes of the 

 CRAB. Angles greater than 4 deg are radioed to the Zeiss operator who enters 

 them into the recorded data. The angles are automatically accounted for 

 during processing of the data. 



39. Corrections made to the data, (except CRAB tilt corrections), are 

 recorded in processing and data-collection logbooks and are coded into the 

 data file. The meaning and format of the codes are presented in Appendix B. 



Special Notes on the Survey Data 



40. A number of surveys within the data set require specific discussion 

 regarding data quality. The early stadia surveys (January to 1 June 1981) 

 have already been described. From approximately 14 December 1982 until 9 

 February 1983, the Zeiss Elta-2 was intermittently producing questionable 

 results which appeared as a systematic vertical error. From 24 February 1983 

 through 28 March 1983, the instrument was being repaired and alternate methods 

 were employed. These included the use of the stadia board and automatic level 

 to determine elevation and a Motorola Mini-Ranger positioning system to deter- 

 mine offshore distance (24 February to 3 March). A loaner Zeiss instrument 

 was also employed (22 March to 28 March). 



41. Because this was an unusually active period of profile response with 

 a number of significant storms occurring, the data during this period have 

 been retained in the data set. They do accurately reflect the changes in 

 profile configuration which occurred, but the horizontal and vertical accu- 

 racies are less than for the remaining CRAB/Zeiss data. 



42. Data prior to December 1981 were saved only to whole feet in dis- 

 tance and tenths-of-a-f oot in elevation (normal accuracy for beach profile 

 data). Because of the greater accuracy of the CRAB/Zeiss data, subsequent 

 data are stored to tenths-of-a-f oot in distance and hundredths-of-a-f oot in 

 elevation. This too has an impact on the overall accuracy of the data. 



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