IRCam Guide

IRCam Setup Guide

Congratulations, your cam has finally arrived! Your new infrared head tracking cam is a high performance machine, and it's going to take some setup to get you dialed in and ready to fly/race. We're going to start by getting your cam assembled and mounted.

Assembly

The IRCam comes partially disassembled to help prevent damage while in transit. You should find 5 pieces. The main cam body, the mounts' main body and tail assembly, the mounts' front arm assembly, the 1/4" 20 UNC Cam Mounting Knurled Thumb Screw, and the IR Filter Cap.

In the image below you'll see a diagram of how to assemble the mount to your new cam. This step is fairly straight forward, but do be careful not to damage the cam. Assemble your cam at a table where you won't risk dropping it. Also, don't install the IR Filter Cap yet, leave the dust cap on the lens until later in the setup.

Mounting the IRCam

The IRCam Mounting System has 5 adjustment points. 2 on the front arms, 1 on the tail, 1 on the foot at the end of the tail, and 1 for the cam rotation on the mounting system. The hooks at the front of the mounts' arms clip onto the top of your screen. And the tail can be adjusted so that the foot presses against the back of your screen.

Adjust the tail so that the cam lens is pointed roughly at where your head will be located while seated. The cam should be offset to the left of center on your screen so that it is directly in front of the LED tracker on your headphones. The tail can be adjusted in two locations.

The front arms can also swing in and out, which helps fine tune the pitch angle of the cam, and also shifts the weight of the cam forward and backward in relation to the screen. If your cam is tilted downward at an extreme angle, you'll need to push the arms together to shift it's weight back to prevent it tipping forward.

Connecting the IRCam

The IRCam uses the Arducam OV9821 Sensor, and is plug n play. Simply connect the USB to your pc and you're all set. No need to install drivers or any other software (aside from Opentrack of course)

Installing OpenTrack

Here is the latest version of Opentrack for Windows:

Opentrack 2023.3.0 Win32 Setup

Windows Settings

Open the Windows webcam settings by navigating to: StartMenu > Settings > Bluetooth & Devices > Cameras > Arudcam OV9821. Once there you will see a screen like below, please change the settings to what you see here:

Lens Focus and IR Filter

The lens on the IRCam has a manual focus. The focal point is roughly in the mid point of the threads. Go ahead and remove the dust cap, and twist the lens until it's view comes into focus. Don't screw it all the way in, it will break the sensor if the lens is screwed down to the bottom of its threads. If you've screwed the lens in beyond the half way point and the picture doesn't come into focus, then start twisting it out until you find it's focal point. The lenses are pre-focused during testing, so it should already be close.

Once your lens is focused, locate the IR Filter Cap and install it now. Try not to twist the lens when pushing the filter cap on as it will knock it out of focus.

With the windows settings still open, you can also use this opportunity to adjust your cams position so that the 3 primary leds are centered in the cams field of view. You'll want to move side to side, look up/down, left/right and make sure the 3 leds stay inside the field of view of the camera. You should see 3 large and 3 small led dots, focus on the large 3 and center them roughly where you see them in the image above. (more on the 3 small leds later)

Opentrack Setup

In this portion of the setup, some things will vary depending on your unique physical setup, such as cam placement, distance to cam, height of cam, etc. As well as the lens you selected for your IRCam (40° or 58°)

Let's start by launching Opentrack. You should see this screen below.

Make sure that the 3 drop downs on the bottom left match what you see above. Then click on the start button. After a few seconds you'll see the preview window display the leds in the cameras view. From here you need to click the Options button.

Shortcuts

The first Tab of Options is called Shortcuts, go ahead and set your center and toggle hotkeys, as well as making sure the Centering Method is set to Roll Compensated.

Output

Next up is the Output Tab. Everything here can be left on defaults.

Relative Translation

Go ahead and click on the Relative Translation Tab. Relative Translation applies the translation after rotation. To explain what that means, it's easiest to describe the scenario where it's used...

When you look over your right shoulder in the cockpit, you are looking behind you in game. However, in the real world, you're still sitting in your seat facing forward toward the camera. So if you lean left to look around the seat, you'll actually lean right instead. Relative Translation fixes this so that when you lean left, your view leans left with you. This is personal preference on whether you use it, but I do recommend it. If you choose to use it, here are the settings:

We're going to skip over the Game Detection Tab. It's there if you'd like to use it, but it isn't necessary.

Tracker/Camera

We'll start with the screenshot here, but please follow the steps below.

The next Tab is Tracker. And this is where we're going to get the IRCam dialed in. The Tracker tab has 4 sub tabs. We're only going to worry about Camera and Model.

On the Camera subtab, you need to make sure the Arudcam OV9281 Camera is selected beside Device.

Width and Height fields. You should start with 640x480, however, 800x600 or 320x240 can also be used if you have trouble with leds overlapping due to being too large, or your led circles disappearing due to them being too small. This will have to due with the distance between your led clip and the camera. For this guide, I am using 320x240, but leave yours on 640x480 until we finish the setup of the Camera tab. Adjust as needed after.

FPS. The Arducam OV9281 sensor is rated at 120hz. However, Opentrack is only registering around 70-80 fps. I've reached out to both Arducam as well as the devs of Opentrack to narrow down the issue, and I will update this guide when I get some answers. 70+ fps is plenty for smooth tracking, but more is better. For our setup though, go ahead and type 120 in the FPS field.

MJPEG Compression. If you're using Windows, check this box.

Diagonal Field of View. This will depend on which lens you ordered. If you selected the 40° lens, enter 40. 58° lens, enter 58.

Dynamic Pose. If you are using the IRTrackstar, or any led clip with a central led offset, check this box, and leave 250ms as default. If you're using an led clip with 3 leds in a straight line with no offset, then leave this unchecked. (it says in parenthesis that this setting is for caps only, never clips... they have lied to you. Check it anyway.)

Camera Settings. Click the open button and adjust the settings to match these below:

Color Channel Used. Select Grayscale (From Hardware), and ignore the Chroma settings

Point Extraction: Automatic Threshold should be checked.

Threshold. Start with this slider at the far right, and inch it back to the left until all 3 leds are stable and tracking even while turning your head and moving around. This slider will need to be adjusted in conjunction with the Min/Max sizes.

Min Size. You may have noticed 3 small leds floating around behind the 3 large leds. I call these the ghosts. This is due to the IR Filter Cap using a mirrored optical glass infrared filter. The leds from the clip shine through the filter, reflect off the curved lens, and bounce again off the mirrored surface of the filter. This isn't a problem however, we just need to tell Opentrack to ignore them, and you do that here.

You'll notice in the screenshot above of the camera viewer, the 3 small ghost leds have a size of around 2.7px. You'll also notice the large 3 primary led dots are over 6px. So, in this case, you can safely enter 4px into the min size to ignore the ghosts and only track the 3 primary dots. Keep in mind, your px sizes may be different depending on your lens fov, resolution settings, distance to cam, etc. But this concept will apply to any px size. Min size should always be larger than the largest px size associated with the ghosts.

Max size. As you may have guessed, this number needs to be larger than the largest px size associated with the 3 primary led dots. In the image above, those would be the red numbers. However, as long as you don't have any background infrared light contaminating your cameras view, you can safely set this much higher. Even though the size of the primary leds is around 6-7px, I have it set to 40 as the max size. If however, you have background lights interfering with your cameras view, you may need to lower it to tell Opentrack to ignore the background noise.

Once you adjust the min/max px sizes, you'll want to adjust the Threshold again to find a spot where all 3 primary leds keep their circles around them, and the 3 ghosts never pop up with white px sizes next to them. Your camera preview should look like this:

Tracker/Model

Now we're ready for the Model sub tab. This will largely depend on the led clip, or hat clip, that you're using. If you're using the IRTrackStar, enter these Model Dimensions here:

Model Position. While looking forward, press Start Calibration. Then move your head using pitch and yaw movement only. Look left/right, up/down. Then hit Stop Calibration.

Filter Tab

Don't confuse this with the Filter sub tab under Tracker. The Filter Tab is a main tab at the top right. The settings on this page can be left default, but may be adjusted to your preference. Here's a brief explanation of what they do.

Rotation Filtering
Smoothing. Smoothing is going to do exactly what it says, smooth the movement to reduce any jitters. If you're using the IRTrackStar, you shouldn't have many jitters at all, so 1.5° is likely plenty.

Deadzone. This is not actually a center deadzone. What it does is ignore minor movements, such as breathing or shaking. And it will do that regardless of where you're looking. For example, if you need to focus on some switches beside you in the cockpit, the Deadzone is going to hold the camera steady while you move the mouse to click on a switch. Set this too low and you may have to chase the switch with the mouse since your view will be moving around. Set it too high and it will induce a small lag between when you start moving your head and when the tracking begins. Default settings are likely fine for most situations. My settings are slightly different, based on personal preference, and you can view them below.

Position Filter. Same concept as above, but rather than the pitch, yaw, and roll, these settings apply to your strafing movements of x,y, and z.

Mapping

Now that we're done with setup, you can click OK on the Options window to close it. Next you're going to Click on the Mapping button from the main Opentrack program. To adjust the curves, Left click anywhere on the line to add a control point. Right click on a control point to delete it.

The screenshots below should be used as a starting point only. Adjust to your preference.

Yaw

Pitch

Roll

Conclusion

That's everything! I hope you enjoy your IRCam as much as I enjoy mine. If you ever have any questions don't hesitate to reach out. You can use the chat button at the bottom right of the page, send an email to rjsimtech@gmail.com, or connect with me on Discord here: https://discord.gg/3ByqnhAVgQ My Discord username is Hollywood83. I'm always happy to schedule a time to hop in voice comms and do a screenshare to help get you dialed in.

Thank you again and happy flying!

Hollywood83