2 Shoeprints The physical contact between the shoe and the surface results in a transfer of the individual characteristics ofthe shoe.Shoes prints are often used to prove that suspect waspresent at a crime scene.
3 3-dimensional impressions Footwear impressions are pressed into a soft surfacesuch as mud.The impression is influenced by the weight of theperson and the type of surface.
4 Casting a 3-dimensional impression Photography Paul Ricketts, 2006
8 Using Alginate to make an impression 1 - alginate powderPhotography Paul Ricketts, 20062 - pour the alginate into a plastic bag3 - about 1/3 of a bag
9 5 - squish the powder and water 4- add water5 - squish the powder and water7 - cut a small hole at a corner of the bagwith scissors6 - thoroughly mixPhotography Paul Ricketts, 2006
10 8 - squeeze out the alginate onto the impression. Work quickly as alginate driesvery fast.9 - carefully pat into place10 - the alginate changes colour when dry -carefully lift from the impressionPhotography Paul Ricketts, 2006
11 The finished impression 10 - wash away as much dirt as possiblePict of finished impression - to doPhotography Paul Ricketts, 2006
12 2-dimensional impressions 2-dimensional impressions occur when an image of theprint is left on the surface.Some 2-dimensional impressions are highly visible –muddy footprints on a cleaned floor – while othersare latent or invisible.
13 2-dimensional impression: Blood Photography Paul Ricketts, 2006
14 Latent 2-dimensional impression: luminol Photography Paul Ricketts, 2006
15 Other impressions Casts can be taken of the impressions of other objects. Eg, tyre tread
17 Tyre tread on groundPhotography Paul Ricketts, 2006
18 ReferencesImagesAll photography by Paul Ricketts, DUIT Multimedia, the University of Western Australia.J. Baines is the model for the sequence of photographs showing taking a shoeprint impression using Alginate.Shoes supplied by J. Dook.Graphic design of slides by Trevor Hutchison, DUIT Multimedia, the University of Western Australia.