# Fps changes when triggers activate
**URL:** https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417
**Category:** General Questions
**Created:** [April 10, 2018, 7:24am UTC](https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417 "2018-04-10T07:24:47Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@morin](https://forum.commonvisionblox.com/u/morin)
#### Post date: [April 10, 2018, 7:24am UTC](https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417/1 "2018-04-10T07:24:47Z")
Hello! I am using cvb drivers to use 2 cameras at the same time. The program i made seems to work just fine, but there is a strange behaviour happening when I put one of the camera on trigger mode (or both of them). When they receive the trigger, they start grabbing, but they auto set a high fps value (sometime to 135, sometime to 90) but it does not change the value inside the properties of the camera. Any clue what could be the problem?
thanks in advance! Best regards,
Pierre-Olivier Morin
---
### Author:  [@CvK](https://forum.commonvisionblox.com/u/CvK)
#### Post date: [April 10, 2018, 11:38am UTC](https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417/2 "2018-04-10T11:38:22Z")
Does the camera actually grab that number of images? And does the number revert back to a lower number after a few seconds?
---
### Author:  [@morin](https://forum.commonvisionblox.com/u/morin)
#### Post date: [April 11, 2018, 12:07pm UTC](https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417/3 "2018-04-11T12:07:00Z")
The camera actually grab that number of images but does not return back to a lower number, its stays at 135 or 90 Frames per seconds.
---
### Author:  [@Sebastian](https://forum.commonvisionblox.com/u/Sebastian)
#### Post date: [April 12, 2018, 7:23am UTC](https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417/4 "2018-04-12T07:23:18Z")
Hi @morin
please try this with the CVB Viewer. If it does not happen there you did something wrong in your code. But this seems unlikely.
If it happens also in the CVB Viewer I assume an issue with the camera the camera settings or the external trigger signal which you use.
CVB itself does not change the framerate automatically. It acquires the images which we get from the camera.
---
### Author:  [@morin](https://forum.commonvisionblox.com/u/morin)
#### Post date: [April 12, 2018, 9:03am UTC](https://forum.commonvisionblox.com/t/fps-changes-when-triggers-activate/417/5 "2018-04-12T09:03:28Z")
Thanks!, i will look this up as soon as i can!