Current emphasis in geomorphology recognizes the need for the accurate
representation of topographic form, reflected in the growth of digita
l terrain and elevation modelling. A key requirement of such strategie
s is the efficient acquisition of information in an appropriate form a
nd at an appropriate resolution to the landform under consideration. T
he traditional use of photographs in geomorphology has been for interp
retation, but developments in photogrammetry may allow the full advant
ages of the photograph as a means of acquiring and storing quantitativ
e information to be used. The photograph can provide information on al
l areas visible on a photograph; the information is acquired retrodict
ively; the photograph preserves the spatial relationship of morphologi
cal units; the collection of photographs requires minimal landform con
tact; the photograph records extra explanatory information; and photog
raphs can be obtained at an appropriate temporal resolution to the lan
dform under investigation. However, optical and mechanical limitations
imposed by traditional photogrammetric approaches have prevented its
rigorous and widespread application to geomorphology. Developments wit
hin photogrammetry, notably the analytical approach, now open up wider
geomorphological possibilities. The analytical approach overcomes the
se limitations through the use of an interactive mathematical model at
the stage of photographic analysis. The obtained information is in a
form directly suited to the construction of digital terrain or elevati
on models. This technique can be used both for landform monitoring and
for the analysis of archival photographs to reconstruct historical la
ndform change.