Colorvu 4mp turret ds 2cd2347g2 lu - grainy images?

[Vauxfan]

Can you give me an idea of what is going on with the side camera?
It's a really graining images compared to the other 1. Camera is a colorvu 4mp turret ds 2cd2347g2 lu

The images appears like it's raining on screen yet it isn't. It's only at night time.
I can only upload a screen shot and not a video for some reason

 

[codlord]

What are your resolution/quality/bitrate settings on that camera compared with the others (check all the streams: sub-stream main stream, event stream, whatever). It looks to me like it's set on a low bitrate.

 

[Vauxfan]

It was OK before. The one thing I did change was the noise setting. I thought it was for the wind noise over the mic. But it's in image. I have set it to 20 from 50. I have now just put it back to 50. Would that do it?

Also. What is 'gain' in image?

 

[David]

Can you give me an idea of what is going on with the side camera?
It's a really graining images compared to the other 1. Camera is a colorvu 4mp turret ds 2cd2347g2 lu

The images appears like it's raining on screen yet it isn't. It's only at night time.
I can only upload a screen shot and not a video for some reason

the top lefthand corner of the image is a lot brighter than the rest of the image, have you tried increasing the exposure time and using BLC or WDR to compensate for the overly bright picture?

post a screenshot of your image and video settings

 

[Vauxfan]

It was better last night after increasing noise reduction level

 

[David]

It was better last night after increasing noise

may be reduce the exposure gain as well, if this is too high it will add noise to the image. I've found some image settings interact with each other and you need to find a happy balance.

 

[JB1970]

Gain amplifies the signal when the exposure is insufficient to produce an image. Unfortunately as @David says, as well as increasing the signal, the gain will increase visible noise as a side effect. Noise is seen as grain/speckles in the image as opposed to blockiness (which is more down to compression artefacts). 3D noise reduction works by looking at individual pixels interpreted as noise and copying the adjacent pixel (space) or previous pixel (time). Clicking advanced allows you to alter these values separately. Increasing noise reduction unfortunately has side effects of it's own, over smoothing/softening the image and introducing ghosting on moving objects. Noise doesn't bother me too much - although it will increase the bit rate (as the noise creates changed pixels), for me it's preferable to a blurred image caused by excessive noise reduction.

Everything is a trade off. Lowering the gain will darken the image, so you'd need to counteract that by increasing the shutter time from 1/100 to 1/50 sec (which will increase motion blur depending on the speed of the target)