What is gain

[saltwater]

I have several 5442 cameras and I'm in the process of fine-tuning all of them. Under the Exposure menu setting, what is 'gain'?



Is gain the same as ISO in normal photography terms? The lesser the gain number, the lesser grain (noise) and conversely the higher the gain number the more grain (noise) in an image for a given shutter speed. For daytime use, some days are dull and overcast and even with DSLR camera shooting at 1/1000+ the ISO (or gain) must be increased significantly albeit knowing grain (noise) will be introduced. Traditional ISO, or usual ISO ranges are from 100 - 6400.

 

[saltwater]

Bump. Anyone?

 

[ajwitt]

I think because you answered your own question in the original post LOL...

From this thread:

Common issues with camera image

Here is a quick guide to what might go wrong with the image of your cctv camera, and how to fix this. MOTION BLUR: This is probably the most common issue, new camera owners run into. Many times on this forum I've seen posts like: "I bought a set of cameras recently. The image looks great on...

ipcamtalk.com

This problem is in direct relation with previous one, the motion blur. Trying to avoid motion blur you shorten exposure time. Having not enough light, the camera starts to rise GAIN parameter. GAIN is an amplification of the image signal. It will brighten the image, but also amplify noise, that is already present in the image. If the environment is really dark, even at slow shutter the camera may have to boost GAIN to a level at which the image will become noisy and unclear. Brighter lens - passing more light to the sensor - as well as bigger image sensor (bigger pixels) have a positive influence on noise level. Noise reduction is a good solution, but may also introduce some other problems. More on this later.
Generally, it is sometimes good to keep GAIN parameter within the limits. Some cameras work great even at highest GAIN values, but other do not look so good. The 4239T is a great camera, but at 100% GAIN - in my opinion - the image is useless. So I set the limit between 0% and 85%. It's all a matter of taste.

 

[bickford]

Try manual 0 - 10 for gain
the camera will adjust the gain alone

BICK

 

[saltwater]

Thanks. I was more wanting confirmation. Now I know that is actually the same as ISO, now it's just a matter of attempting to figure out the gain number settings. Ideally, in good light, in normal photography we set the ISO to 100 - 200 range (no noticeable difference in quality, but once at 800+ noticeable grain appears. So, for gain purposes, what would be an unacceptable high figure? As I type this a comment came in just above suggesting 0 -10. Ok, I've got some playing around to do, all based around shutter priority.

 

[bickford]

it will depend on what you want to do, read the license plates? identify a person? it will also depend on the level of light around your camera, the speed of exposure ...
I never use more than 60% of gain.

BICK

 

[saltwater]

My goal is to knock out motion blur as much as possible, but it is a balancing act with all the variables and what I perceive to be an acceptable image/vision.

 

[bickford]

My goal is to knock out motion blur as much as possible, but it is a balancing act with all the variables and what I perceive to be an acceptable image/vision.

nobody here likes motion blur but if you don't have any light in your scene you will have to switch to black and white and sometimes add a complementary infrared projector or led light for night color pictures.

To identify i use shutter speed 0 - 10 ms and sometimes if there is enought light i use 0 - 4 ms.

On these 2 cameras (left is Hikvision colorvu V1 , right Dahua turret 5442 ) camera on the left shutter is 1/100 and on the right 1/250
but as you see it , street light help a lot


BICK

 

[saltwater]

Yep, light is key.