Backlight compensation settings are not applicable for WDR mode. The Exposure adjust speed is also not available with WDR. Finally, gain control is not available with WDR mode.

4.2 WDR Shutter Speed 1 and 2

Shutter speed can be controlled for both camera exposures. This setting sets a fixed shutter speed for each frame. If there is variation in lighting from frame to frame or at different times of day, setting a fixed value may result in suboptimal performance when lighting has changed from the levels for which it was optimized.

4.3 Shutter Speed Min and Max

Shutter Speed Min and Max settings apply limits for both of the exposure modes. This allows Auto behavior of each exposure to be applied but sets a limit on how low and how high shutter speed will vary. Behavior is similar to that described for non-WDR mode.

4.4 Night Vision Settings

You can enable the IR lights or leave them in Auto. When in Auto, IR will be enabled in low light. On will force IR lights to on always.

4.5 EXPOSURE MODE

Options of Face Prioritized and Scene Prioritized.

Face Prioritized

Camera exposure is optimized for any faces in view of the camera. When set to Face Prioritized, camera will adjust exposure to optimize for the largest face in view of the camera. This results in a dynamic exposure. This is the prefered mode for facial recognition.

You will read below, how Scene Exposure Region can be used to give the camera a hint on what to set the exposure to when faces are not present

Scene Prioritized

Camera exposure is optimized for entire scene. When in this mode, camera does not adjust exposure based on presence of faces in the video. Exposure is optimized for the entire scene. While this mode is useful for creating an optimal video recording of entire scene, it will not optimize exposure to the face and thus have negative impact on face recognition.

Example with strong backlight

Scene Prioritized	Face Prioritized

4.6 SCENE EXPOSURE REGION

Determines the camera exposure when no face is present in the view of the camera. This setting allows you to give a hint to the camera to set exposure when no faces are in view. This is done by selecting a region of the video to set exposure. Possible values are:

Top 25%
Top 35%
Top 50%
Center
Bottom 50%
Bottom 35%
Bottom 25%
Custom

Setting this value to the exposure of where faces will appear in the video will reduce the amount of time I takes for the camera to adjust exposure for the face.

Examples

Incorrect Settings - Exposure zone set to region of strong backlight

Face not in view	Face in view

The problem is that the camera has to adjust from a very dark exposure to a very bright exposure to let sufficient light in to properly light the face. This takes a few hundred milliseconds. For fast moving objects, you may lose precious moments to perform recognition.

Correct Settings - Exposure zone set to region of similar lighting

Face not in view	Face in view

💡Use Scene Exposure mode with face in view to chose which region offers the best exposure on the face. Adjust the region, including custom if needed, until the face is well lit. Then change exposure mode back to Face Prioritized.

Default value for Scene Exposure Region is Bottom 35%. This is most often the optimal location but may not work if floor is brightly lit from outdoor reflection.

4.7 Exposure Level

Allows the exposure to be boosted or attenuated from what the camera considers optimal. This value can be as high as 400% (4x brighter) or as low as 25% (4x darker). It is recommended to leave this at 100%, but the setting may be modified if SAFR is consistently incorrectly setting exposure.

4.8 Exposure Adjust Speed

Controls speed at which the camera adjusts exposure. Default is 72%. Values greater than 72% reduces the time it takes for the camera to adjust exposure. Decreasing this value increases the time it takes to adjust exposure.

Increasing this value too far may result in "yo yo effects". That is, due to the speed of adjustment, the camera may overshoot and oscillate the exposure back and forth.

Adjusting this value may be useful in case where faces are moving very fast through the view. If the person is moving too fast, the camera may end up adjusting exposure for a face that is no longer present in that location. Speeding up the Exposure Adjust Speed may help in this case or slowing it down may avoid adjusting exposure too quickly and keeps exposure

4.9 Backlight Compensation

SAFR Camera is designed to compensate for backlight conditions. Backlight Compensation setting provide some control over that feature. Possible values are:

Auto
Slight backlight ( outdoors)
Medium backlight ( outdoors )
Medium strong backlight (typical outdoors)
Strong backlight (indoors / outdoors )
Very strong backlight (typical indoors)
Extreme backlight ( indoors)

Auto mode attempt to adjust exposure under typical conditions. Other options allow you to provide a hint to the camera as to the type of conditions it is facing which will improve its ability to handle those conditions.

Backlight Compensation primarily manages the shutter speed. Shutter speed is also controlled by the Minimum and Maximum Shutter Speed settings. SAFR Camera handles these settings by applying the setting that imposes the greatest constraint. For example, if Maximum Shutter Speed is set below what the Backlight Compensation setting would set for the current conditions, then the Maximum Shutter Speed will be applied.

4.10 Maximum Shutter Speed

Max Shutter speed is one of the tools to use to handle backlighting. Faster Shutter speeds will decrease light allowed into the camera and thus darken the view. Setting Max Shutter Sped prevents the camera from darkening the face image too much due to bright background.

4.11 Minimum Shutter Speed

Lower shutter speed results in motion blur. Setting a higher minimum shutter speed can reduce or prevent motion blur.

Normally you want the minimum shutter speed to be as low as possible to increase exposure (light on the face).

At 1/120 you will typically not get motion blur. But at this speed, you may have insufficient light.

4.12 Max Gain

When the lighting gets reduced, the camera applies more gain to the image. Higher gain adds noise to the image. This results in faces looking grainy due to the noise in the signal resulting from the gain. To control noise, you can limit the Max gain setting. But by doing this, you reduce the brightness. Gain should only be adjust once improvements from adjustment of shutter speed and iris have been exhausted.

4.13 About Zoom, Focus and Iris Controls

Zoom, focus and iris controls are located below the video preview region on the Camera settings page. All three settings have similar controls as shown below.

A screenshot of a computer

Description automatically generated

Controls on the left are for adjusting the setting in one direction while controls on the right adjust in the other. Any changes made are applied immediately and visible in the preview window.

Each of the buttons results in a varying degree of change as noted in the image above.

4.14 Iris

Another control that is related is Iris settings. The SAFR Camera allows control over the Iris. Opening the Iris all the way results in light diffusing and reducing focus. So increasing Iris will limit the ability to focus the camera, especially at close range. The diffusion is not as pronounced further from the camera. But increasing iris also reduces the depth of focus or the range in which a subject is in focus. Reduced range of focus means you have less time that the subject is in focus.

Reducing the Iris (making it smaller) results in a larger depth of field and you can maintain focus on the subject for a larger distance.

4.15 Zoom

Use the zoom controls to adjust the width of view in the region of interest which is usually a choke point where faces are constrained to a narrow and face tend to be looking in a single direction. Zoom should be applied so that faces are as large as possible. With a 4k camera, the width of view at the target area should be no more than 20 feet wide. Wider views will result in resolution on the face being too low for high quality recognition. If needed, use 2 or more cameras to cover wider areas (1 camera for every 20 feet).

Controls on the right side (>, >> and Tele) will increase pixels on the face. Controls on the left side (Wide, <<, and <) will decrease pixels on the face.

4.16 Focus

Auto-focus is not supported at this time. Focus should be performed after zoom adjustments.

To perform manual focus, perform the following steps

Start from the largest change buttons (“Near” and “Far”)
Press Near or Far until camera goes into focus and then out
Identify the end points where camera is out of focus based on least number of clicks.
Go to one extreme and go back one half that amount.
Perform steps 1-4 with the << and >> buttons
Finally, repeat steps 1-4 with the < and > buttons