This downloadable file is an arrangement of twenty-one steps in 5% density increments. Note that the evenly distributed densities only apply to the digital image. The actual opacity of the digitally printed negative, for example to ultraviolet, will vary depending on the printer inks and film base.
A step wedge is also known as a transmission step wedge or step tablet. It is a strip of transparent film, with at least 12 zones of density, or steps, progressing in regular stages from the base transparency of the film to almost completely opaque.
A step wedge is used to compare platinum/palladium prints made under varying conditions. Standardized step wedges are made by Precision Digital Negatives, Stouffer, and others. They may also be printed digitally from a file such as above, or with an inkjet printer setup using calibration targets, such as those available from Cone’s Piezography system.
Cone/Inkjet Mall’s PiezoDN
Precision Digital Negatives, USA
Stouffer Industries USA