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Step 2 – Have the client choose one or more objects of interest to be used as their mannequin and / or props . Some options to consider are a person , license plate , weapon , backpack , animal , or a doohickey from their facility that needs to be monitored or that tends to go missing .
Step 3 – Place the objects in a location which allows you to stand away from the object and observe it . You may need to take a chair or ladder with you to help you position the props so the wind doesn ’ t them blow over while you are conducting the exercise . The closest observation point on the HEED Index is 12- feet , and the farthest observation point is 1,800-feet .
Step 4 – Scroll down the HEED Index until you get to the Camera Design Resolution you wish to observe . For example , say you are interested in understanding what 50-PPF ( pixelsper-foot ) looks like .
Find 50-PPF on the chart , then move your finger left-or-right to find the associated distance .
In this example , you will note that you need to position yourself 120-feet away from the mannequin / props and observe them .
When your client is the noted distance away from the mannequin / props and observes them with his / her own eyes , they are seeing what the associated pixels-per-foot looks like .
July 2017 Edition
They are experiencing the definition of the visual acuity terms . That is all there is to using the HEED Index .
To create realistic expectations , you really need these four items :
Why the sunglasses and mesh face-mask ?
Modern security cameras are 100 % digital devices . Human eyes are 100 % analog devices . Our eyes are vastly superior to security cameras .
The sunglasses and mask make our eyes less awesome , so the HEED comparison is more accurate .
The sunglasses tend to darken shadow areas and reduce the dynamic range of our eyes . This is important because cameras tend to resolve less detail in the shadow areas than our eyes do .
If you notice dark , shadowy areas in the scene , know the camera will likely struggle to provide much detail in those areas .
Sunglasses are also useful indoors and at night . The majority of security cameras do not see as well in low light as our eyes do .
Wearing dark sunglasses will help you and your client detect areas where cameras with improved low-light performance need to be specified , or where the site needs improved lighting .
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