# Dual Stereo only

Source: https://forum.modalai.com/topic/1275/dual-stereo-only
Category: VOXL 2 and VOXL 2 Mini (https://forum.modalai.com/category/26/voxl-2-and-voxl-2-mini)
Tags: voxl-2
Posted: 2022-08-31 17:18:11 UTC by mawriyo
Replies: 2 · Views: 785

## mawriyo · 2022-08-31 17:18:11 UTC

Has anyone had luck running camera server / voxl-streamer without having the HIRES/Tracking cameras plugged in? Even though I disable it in the configuration file in /etc/modalai/voxl-camera-server.conf it seems like it MUST be plugged in in order to use the dual stereo feature. 
```
------ voxl-camera-server: Starting camera server
	Started Camera: stereo_front
ERROR: Get camera 4(stereo_rear) info failed!
Encountered error starting camera: stereo_rear, exiting
	Stopped Camera: stereo_front
```

## Reply by Guest · 2022-08-31 17:41:39 UTC

Hi,

If you physically unplug two of the cameras the IDs for the other cameras will decrease to populate the first N IDs. In the normal setup front stereo is ids 0 and 1, tracking is 2, hires is 3, and rear stereo is 4 and 5. If you've unplugged the tracking and hires you'll need to change the rear stereo ids to 3 and 2 instead of 5 and 4 since there will only be 4 cameras. I.E:
```
 {
	"name":	"stereo_rear",
	"enabled":	true,
	"frame_rate":	30,
	"type":	"ov7251",
	"camera_id":	3,
	"camera_id_second":	2,
	"independent_exposure":	false,
	"ae_desired_msv":	60,
	"ae_filter_alpha":	0.600000023841858,
	"ae_ignore_fraction":	0.20000000298023224,
	"ae_slope":	0.05000000074505806,
	"ae_exposure_period":	1,
	"ae_gain_period":	1
}
```

## Reply by mawriyo · 2022-08-31 20:10:59 UTC

Thanks for your reply! I got it working. Thank you!