# stereo calibration problem & ask for calibration results

Source: https://forum.modalai.com/topic/1521/stereo-calibration-problem-ask-for-calibration-results
Category: Development Drones (https://forum.modalai.com/category/44/development-drones)
Tags: m500
Posted: 2022-11-03 02:05:18 UTC by malvin
Replies: 9 · Views: 1594

## malvin · 2022-11-03 02:05:18 UTC

Hi ,
I have some issue when i run voxl-calibrate-camera stereo.
I cant do stereo calibration.
Because the VOXL web portal shows nothing on camera calibration overlay page.

So, may i ask for all the camera calibration results?
m500 seria number : M2100000FU4

## Reply by Chad Sweet (ModalAI staff) · 2022-11-03 06:12:06 UTC

What do you mean by nothing on the portal camera calibration page? Can you see the stereo image frames? If not, the calibration file won't help. Can you share a screen capture of what you mean?

## Reply by malvin · 2022-11-03 10:32:57 UTC

Dear Chad,

Thanks for the reply.
I can't see the stereo image.
![image0.png](https://forum.modalai.com/assets/uploads/files/1667471249061-image0.png) 

By the way, voxl- calibration-camera tracking works fine on the portal.

## Reply by Guest · 2022-11-03 16:50:26 UTC

Can you see the raw stereo camera stream in portal?

## Reply by malvin · 2022-11-04 02:11:41 UTC

Ya, it works well.

![image0.png](https://forum.modalai.com/assets/uploads/files/1667527831794-image0.png)

## Reply by malvin · 2022-11-07 05:41:35 UTC

Hi all,
We followed the following tutorial to upgrade the flight system image to version 1.3.1.
https://docs.modalai.com/Qualcomm-Flight-RB5-system-image/

But We didn't save the calibration files in /data/modalai and lost them.

The voxl-version now :
![Screenshot from 2022-11-07 13-07-44.png](https://forum.modalai.com/assets/uploads/files/1667799139232-screenshot-from-2022-11-07-13-07-44.png) 
voxl-inspect-services :
![Screenshot from 2022-11-02 15-03-42.png](https://forum.modalai.com/assets/uploads/files/1667799604858-screenshot-from-2022-11-02-15-03-42.png) 

==========================================================
So I tried to calibrate the stereo camera by voxl-calibrate-camera stereo by following this guide.
https://docs.modalai.com/calibrate-cameras/

The problem is that the portal didn't display the stereo calibration images (Camera Calibration Overlay),
but I can see the raw stereo camera stream in portal.
![image0.png](https://forum.modalai.com/assets/uploads/files/1667799471576-image0.png) 
@Chad-Sweet @Alex-Gardner Could you give me some advices?

Thanks.

## Reply by Guest · 2022-11-07 16:28:04 UTC

Are you trying to calibrate "stereo" or one of the specific ones, when we have multiple sets of stereo cams they're named "stereo_front" or "stereo_rear" and you'll need to specify when running the calibration tool

## Reply by malvin · 2022-11-08 08:54:10 UTC

I can calibrate stereo by using "stereo_front" and "stereo_rear" now.
But I cant detect the chess board in a frame which rectangle is small.

I will make a new chess board for calibration.
Thanks!

## Reply by dtsbourg · 2023-09-28 19:02:36 UTC (in reply to malvin)

@malvin said in [stereo calibration problem & ask for calibration results](/post/7109):
> I cant detect the chess board in a frame which rectangle is small.

Hi! I am having a similar issue. Which checkboard did you make in order to successfully run calibration when the rectangle is small?

## Reply by tom (ModalAI staff) · 2023-09-28 19:11:45 UTC (in reply to dtsbourg)

@dtsbourg There is some good info here: https://docs.modalai.com/calibrate-cameras/