5.6　Photograph Annotation

5.6.1　The photograph annotation should be divided into route annotation and detailed annotation.All annotation work should be carried out by combining indoor interpretation，field annotation，as well as measurement with instruments.

5.6.2　The indoor interpretation shall be carried out by means of stereoscopic viewing and image identification.For micro-surface features and micro-relief that are difficult to interpret accurately and other surface features which may affect the route，field annotation shall be conducted.For the annotation of crossing-over，parallel-adjacent or new surface features，and changing terrains，measurement with instruments should be carried out.

5.6.3　The photographs must be annotated in such a manner that they are interpreted accurately，described clearly，the cartographic symbols are used appropriately and located correctly and various notes are correct，unambiguous and legible.The classification and properties of surface features and landform shall be determined through annotation.

5.6.4　For crossed power lines，the voltage level，tower types and heights shall be marked on the photographs，while for power lines at 35kV and above，the heights of towers neighboring the route shall be surveyed in the field.The conductor height at the sag point of power lines crossed by the route shall be surveyed according to the design requirement.

5.6.5　For crossed communication lines，overhead cables，and overhead optical cables，their types，grades，tower types and heights shall be marked on the photographs.

5.6.6　For crossed overhead cableways and aqueducts or other similar surface features，their positions and heights shall be marked on the photographs.

5.6.7　For crossed underground cables，optical cables and piping，their types and positions shall be marked on the photographs.

5.6.8　For crossed highways and railways，their names，traveling direction，and distance to the crossingover point shall be marked on the photographs.While for crossed rivers，their names，traveling direction and flowing direction shall be marked.

5.6.9　For cash crops and forests within the corridor along the line，the scope and height shall be marked on the photographs.

5.6.10　Persons responsible for annotation shall sign their names and annotation date on the annotated photographs.