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1. Turn on the lights
2. Click the START GRAB button
3. Move the camera over the white square on the ColoChecker standard. 
4. Use the mouse and draw a ROI (Region of Interest) square with only the white square inside.  The RGB values and Ratio values will only be calculated for the pixels inside the ROI.
5. Go to the Gains-Black-Shades-Flat tab and click the Clear All Gains and click Clear Black Gains
6. Go to the Rates and Exposure tab and set the Green Lock to Off

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Lets say in the above example you could not get the red to to 240 you have several options:

1. Lower the lights for increased intensity
2. Open up the f-stop for more light
3. Increase the line rate (slower scan speeds) so that you can increase the exposure period
4. Use gains to amplify the signals.

Using gains is generally the simplest choose because the other choices are not practical. The down side of using gains is they amplify both signal and electrical noise, so use with alight touch.  In the next section will discuss how to use the gains but remember you will likely move back forth between setting exposures and gains to optimize the camera.  It is an iterative process.

Open the Gains-Black-Shades-Flat tab.  Keeping with the scenario that we cannot obtain 240 on the red channel , the first thing we'll do is adjust the Master Gain until the red is in the 240-245 range.  If the Green and Blue are two high you can apply negative gains to those channel until get the ratios to 1 or go back to the exposures and the their exposure levels.  The later method is preferred. 

Using exposures and gains you have now balanced the White ColorCheck square in the 240-245 range it is time to set the dark response of the camera

Before Starting:

• Note which version of standard you are using. Each color standard values vary based on the version and the manufacturer of the standard. The XRite Colorchecker 2019 (MacBeth standard, Figure 5) is the preferred card to use for calibration. The program is set up to use the White and Black squares on the XRite Colorchecker (MacBeth standard). On the Xrite color checker standard the RGB values of White and Black are listed here for various illuminants. White RGBs are 242, 242 and 236 and and black RGBs are 49, 49, 50 (those values are calculated using illuminant D65), as of 01 Dec 2021 there is discussion that we will use RGBs calculated under illuminant A as it better matches our LED lights. Using illuminant A the RGBs for white is 240, 242, 235 and black is 50, 50, 50. For the QP 101 v4 card, the RGB values are 235, 235, 235 (light grey), 111, 111, 111 (medium grey), and 80, 80, 80 (dark grey) (Figure 6). All SHIL calibration standards are found in drawer PP-2B.
• Obtain the 3D standard (Figure 5) and the gray silicone mat standard from PP-2B.
• Set camera f/stop to either F/16 or F/22 (Figure 7). The camera manufacturer suggested F/22 as the preferred f/stop for scanning with the our light set up however we have found F/16 works well for our section halves and is the most used f/stop for calibration and scanning sections. For hard rock cruises, where 360° whole round scanning is required, a larger f/stop number maybe required.
• If you haven’t set the camera’s height, now is the time to do so!  See the section Camera Height Adjustment at the end of the calibration section. The camera height should not need to change between expeditions.

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