21-Step Screen Exposure Guide

Stouffer's 21-Step Exposure Guide

These guides give you 21 steps of photographically shaded film from 100% total black opaque down to 100% total clear.   Use these as a simple method to test for correct exposure.  Once your correct exposure is determined, put one on every screen to be exposed so you can maintain your settings.

Directions:

• Place on screen alongside your positive.
• Expose at your normal time.
• If Step 7 or lower (6,5,4,3,2,1) washes out, you are UNDER-exposed
• If Step 8 or higher (9,10,11,12-21) does NOT wash out, you are OVER-exposed*
• If Step 7 does NOT wash out and Step 8 DOES wash out = perfect exposure time
• * If the upper steps(17,18,19,20,21) do NOT wash out, your screens may be pre-exposed. Be sure to dry screens in complete darkness and use our Screen Room Safe-Light fl tube sleeves.

In the picture above, Figure A is a correct exposure time.  Figures B & C are both under exposed.

Use the following chart to figure out how long to increase or decrease your exposure.  

For example:

• To INCREASE the number of Steps that are NOT washing out, multiply your original exposure time by 2.82 to move 3 Steps HIGHER.  
• To DECREASE the number of Steps NOT washing out, multiply your original exposure time by .50 (or 50%) to move 2 Steps LOWER