^{What is the difference between Calibrated and Uncalibrated guides?}

You can expect the same quality from an uncalibrated product as a calibrated product. Everything we make is produced with the same detail and control. Calibrated and uncalibrated products come from the same batches in a production run.

When a guide is calibrated each step is read with a densitometer and those readings are recorded for reference. This provides the exact optical density value that can be used for densitometry, sensitometry and, scanner and medical imaging calibration.

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^{How to use the T2115 21 step}

Instructions for Photopolymer plates:

Youtube video for using the Stouffer 21 step for Photopolymer Plates

Instructions for Lithography

1. Set your contact printer or vacuum frame to make several trial exposures on separate pieces of film, with each exposure for a different length of time.

2. Make three exposures: one determined by past experience or the exposure normally used in daily production, one for less, and then one for more. It may be necessary to repeat this testing procedure using different exposure times.

3. Process the test negative for the time and temperature recommended by the film manufacturer. It is important to keep processing consistent.

4. Examine the step tablet/wedge image on each of the negatives. Select as the best the negative in which step 7(on a 21 step wedge) is developed to a dense black, with step 8 only slightly dense. Step 7 will be the aim point for normal copy.

There are many different ways for exposing plates. There are an abundance of different exposure systems and processing techniques. The one constant is the step tablet/wedge. Use the step tablet/wedge as a benchmark for all exposures to achieve accuracy and repeatability.

To find the exposure factor to hold more or less on the Stouffer 21 Step Platemaker Sensitivity guide, follow the chart below.

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^{How to use the TX9 Exposure Guide}

Lay the Exposure Scale on top of the photo paper being exposed (either B&W or color) and set your timer for an exposure that is dense for the negative you are printing. Process the print and pick the step that matches the result you want, noting the step number. Go to the exposure chart (included in the kit) and find your new exposure. There are two scales included in your kit. One is in 1/3 F-Stop increments for standard use and the other is in 1/6 F-Stop increments for more precise control.

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^{How to use the TP (Tranparent Projection) Scales}

The TP guides are designed to help determine paper grades, exposure consistency, and Zone System techniques. It can be used by contact printing or by projecting the image onto the paper surface. Once you have a base exposure for your testing it will help you determine your density range by showing how many steps are visible. Each step has an optical density of .15 which equals 1/2 F-stops of exposure (for the 21 step). For example, if your test shows 10 steps of density from Dmin to Dmax you are achieving a 5 F-stop range of density from that particular paper/negative combination. To use the TP guide for Zone system work you will have to pick a subject in the image to be printed and decide which Zone you want it to fall into. Refer to the test strip from the TP guide to determine which step falls into the same printed Zone and adjust your exposure accordingly for the negative exposure.

Of course the best way to become comfortable with using the TP guide is by testing. Knowing that the steps of the 21 step represent 1/2 F-stop increment values will help in calculating your various tests and exposures.

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^{What are the sizes/dimensions of Stouffer's standard guides}

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