The Stouffer 21-Step Transparent Guide is heralded around the world as "the platemaker's choice". It serves as a gauge to evaluate the variables encountered in the exposure and processing of lithographic plates and photographic materials by contact. If indicates the direction and magnitude of exposure or processing adjustments necessary to achieve the desired results. It is also used with contact positives, silk screen, printed circuit boards, and most other photographic applications for judging results, determining speed and contrast for emulsions, and hardness of coatings.

^{Stouffer has a wide range of transmission step wedges that are used in the various industries requiring photosensitive quality control devices. Several sizes and formats are offered to meet most needs. This listing covers the most widely used step wedges:} 

 

Part Number	Steps	Density Increment	F-Stop Equiv.	Dmax	Size
T1015	10	.15	1/2	1.40	1/2 x3 3/4"
T2115	21	.15	1/2	3.05	1/2 x 5"
T3110	31	.10	1/3	3.05	3/4 x 8"
T4105	41	.05	1/6	2.05	1" x 9 1/2"
T4110	41	.10	1/3	4.05	1" x 9 1/2"
T5100	5	1.00	N/A	4.00	2" x 4"

^{For critical densitometry with traceability, the Stouffer T2120CC and the T1530CC meets and conforms to those needs. Densities of the T2120CC and T1530CC compare with those of a National Institute of Standards and Technology (NIST) Standard Reference Material No. 38120C Step Tablet by means of a densitometer that conforms to conditions specified in American National Standards Diffuse Transmission Densiy A.N.S.I. PH2. 19-1986. There is also the Stouffer XT1725CC step wedge produced on X-Ray film which conforms to NIST No. 38100C.}