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tesla
February 8, 2017, 17:25:58
Hi

I have a DFK Z12GX236 camera and I am driving it with a 100 Hz external trigger.
It works pretty good at 100fps RGB32 1280x720 except the following issue :

Sometimes, when the 100Hz starts, the image has some random wrong colour decoding.
Some frames have the correct colour, some have a tendency to violet, blue, red. :
18801881
The average output is some violet tone.


The normal shall be :
1883



Can you help me please ?


Thank you in advance

Stefan

Stefan Geissler
February 9, 2017, 09:59:14
Hello

First of all: Thank you for also sending the normal image! Usually this is not included and I have to guess, what could be wrong and what is the expected image.

You run the camera with 100Hz external trigger really on the edge, so I guess, on the bad images the camera reacts on a second trigger, while is not supposed to do so. I guess, triggering with 95Hz wont create the problem. Thus I suggest to use a little bit smaller video format or a lower trigger frequency.
I just wonder, the max FPS is 100 fps, why do you need to trigger the camera additionally? You could run the camera free too.

tesla
February 9, 2017, 10:29:19
Hi Stefan,

thank you for the answer, now I can go a little more into details.

Actually I need to work at 100Hz and I use an external trigger for time precision and synchronisation with other devices.

Here is the loop how I make my measurements :

Loop:
- I receive a message from another device which says that 100 Hz will start in 1s and it gives me the timestamp of the first edge to come.
- I call my function StopLiveCamera, Load Camera Settings for 100fps, 1280x720, external trig, etc. and after loading settings I call StartLiveCamera().

- My measurement lasts for 2 sec and then I stop the image flow.


So, the problem in my loop is the following :

When the image stream starts, it can be good - so do nothing - or, it can be with these wrong colours.
Everything is in the start of the stream, and affects all the buffer that will be taken.


The question I was wondering :

Is there something I am missing in the settings to force?
Something like RG, GB debayer order ? But this is not available in RGB32 mode. Only in Y800 which I don't use.



Hope I am more clear,



Cheers


Stefan

tesla
February 13, 2017, 09:38:07
Hi Stefan,


do you have an idea for my second reply ?


Thank you in advance,


Stefan

Hello

First of all: Thank you for also sending the normal image! Usually this is not included and I have to guess, what could be wrong and what is the expected image.

You run the camera with 100Hz external trigger really on the edge, so I guess, on the bad images the camera reacts on a second trigger, while is not supposed to do so. I guess, triggering with 95Hz wont create the problem. Thus I suggest to use a little bit smaller video format or a lower trigger frequency.
I just wonder, the max FPS is 100 fps, why do you need to trigger the camera additionally? You could run the camera free too.

Stefan Geissler
February 15, 2017, 08:52:41
Hello

As I wrote, I think the problem is caused by triggering the camera with 100Hz while the camera runs with 100 fps. You can encounter problems with a trigger pulse firing, while the camera is busy, so it restarts the image.

So you either use a lower trigger frequency or you make the vide format a little bit smaller, so you can run the camera with higher fps.

tesla
February 21, 2017, 08:47:22
Hi Stefan

you are right, I've tested all possibilities and even changed color formats to Y800 instead of RGB32. I cannot work at 90 or 95Hz. A smaller image format solves the problem only at half of the image size 640x360 instead of 1280x720. This is not suitable for me. The violet-blue offset occurs even with the internal clock of the camera (without ext.trigger).



So here is my question :

- do you have a firmware update for the camera DFK Z12GX236 which could solve this issue ?
- do you have another camera which is more performant and can handle 100fps at 1280x720 or higher?


Thank you in advance


Stefan



Hello

As I wrote, I think the problem is caused by triggering the camera with 100Hz while the camera runs with 100 fps. You can encounter problems with a trigger pulse firing, while the camera is busy, so it restarts the image.

So you either use a lower trigger frequency or you make the vide format a little bit smaller, so you can run the camera with higher fps.

Stefan Geissler
February 21, 2017, 09:31:56
Hello

I meant to use some lines less by creating an ROI, e.g.
ic.videoformat = "RGB32 (1280x620)";
This should result in a higher frame rate.
How does your trigger signal look like? Is it a clear signal rising from 0V to 5V without any noise?
What is the the serial number and used firmware version of your camera?

Stefan Geissler
February 21, 2017, 11:32:10
Just an idea...

Did you enable "Jumbo Frames" on your network controller? If not, please do so. Use a size of e.g. 4kB.

tesla
February 21, 2017, 13:37:48
Yes of course.

The camera cannot make 100fps without Jumbo frames. I am using 9kB.
Without jumbo frames you can make only 50 fps at 1280x720.



Btw, how do I read the firmware version ?


Thanks


Just an idea...

Did you enable "Jumbo Frames" on your network controller? If not, please do so. Use a size of e.g. 4kB.

Stefan Geissler
February 21, 2017, 15:39:13
Yes of course.
Btw, how do I read the firmware version ?


It is shown in the GigE IP Config tool.

Stefan Geissler
February 21, 2017, 15:53:24
Which exposure time do you use?

tesla
February 21, 2017, 16:54:58
I use 1/250s


Which exposure time do you use?

tesla
February 21, 2017, 17:12:24
It is shown in the GigE IP Config tool.


model DFK Z12GX236
serial no. 18510303
firmware rev 758, hw rev 17

Stefan Geissler
February 22, 2017, 08:36:27
Thank you. I would like you to create a request at http://www.theimagingsource.com/en_US/company/contact/ so I can sent a newer firmware to you. But I am not sure, whether this will solve your issue.

Your camera is more than 1,5 years old. Did the problem occur over the whole time or is it new?

We tried with a similar 23GX236 and were not able to reproduce the problem.

The firmware engineer told me, technically it is not possible to trigger the camera with 100Hz if it runs with 100fps. However, it seemed to work on our computer.

tesla
February 22, 2017, 09:10:23
We have bought this camera one year ago. It existed all the time, but became disturbing when the development advanced.
Please tell me about 23GX236. What resolution it was and what is the max fps at this resolution for this camera.

The problem for us occurs every 2nd or 3rd start of stream. Everything is in the start of stream. If it starts well, it will stay well.

We have two cameras, probably coming from the same batch, we swapped them, no change.


I will make the dev request. Thank you.


Stefan


Thank you. I would like you to create a request at http://www.theimagingsource.com/en_US/company/contact/ so I can sent a newer firmware to you. But I am not sure, whether this will solve your issue.

Your camera is more than 1,5 years old. Did the problem occur over the whole time or is it new?

We tried with a similar 23GX236 and were not able to reproduce the problem.

The firmware engineer told me, technically it is not possible to trigger the camera with 100Hz if it runs with 100fps. However, it seemed to work on our computer.

Stefan Geissler
February 22, 2017, 12:23:44
The DFK 23GX236 is the same as your Z12GX236, but without motorized zoom lens.


Everything is in the start of stream. If it starts well, it will stay well.

Ok.