Issues after advanced camera calibration

[sanatan Rajagopalan]

Hello, 

I am having some strange issues with bottom vision after advanced calibration. Below are the screen shots before and after enabling the advanced calibration. Any idea what could be happening?

Regards

San

[sanatan Rajagopalan]

More screenshot of the calibration details:

[Toby Dickenson]

Please share your machin.xml after calibration

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[Jan]

Hi San!
The accuracy and residual errors are huge. They are expected to be in
order of 10um. Huge errors are usually the result of the nozzle tip not
been detected reliably. I'd recommend to retry and monitor the progress.
You may need to adjust the vision setup and parameters. With default
settings of the vision pipeline you shall find debug images in the
.openpnp2 folder.

Jan

On 22.01.2026 17:30, sanatan Rajagopalan wrote:
> More screenshot of the calibration details:

> More details.png
>
> On Thursday, January 22, 2026 at 10:26:41 AM UTC-6 sanatan Rajagopalan
> wrote:
>
> Hello,
>
> I am having some strange issues with bottom vision after advanced
> calibration. Below are the screen shots before and after enabling
> the advanced calibration. Any idea what could be happening?
>

> Before.png

> After.png
>
> Regards
> San
>
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[tonyl...@gmail.com]

Look at your residual error plots. They show you have upwards of 5 or 6 millimeters of residual error - they should be 2 or 3 orders of magnitude lower. Most likely you are having nozzle misdetects during the calibration process. You need to put a shade behind your nozzle tip to block all those bright spots you have. You may also need to do something with your nozzle tip to darken it as well. It can also help to darken the room (turn off overhead lights) while you run the calibration.

[sanatan Rajagopalan]

Hi Jan, Tony,

I am going to try the advanced calibration again.

I first I just used a permanent black marker to make the nozzle background black. However there was quite a bit of shine.

So I decided to try one of those black 2.0 type of paints to make it really dark. It works but has very rough edges and any uncovered or poorly painted parts comes up as those spaces. 

Will go back to permanent marker and try again. 

Thanks

San

[tonyl...@gmail.com]

Don't forget about putting a (permanent) shade behind the nozzle tip as well. Not only will it help with the camera calibration it will also help when actually using the camera to detect part leads during a job. When you have a part on the nozzle tip and it is centered over the bottom camera, you really don't want to see any bright spots in the images other than those due to the part leads.