Gain or exposure compensation better?

Cj500

Getting the hang of it
Jul 5, 2018
91
53
LA
I'm still working on dialing in my SD49425XB-HNR PTZ after a few years. I can't seem to find the balance between avoiding motion ghosting, avoiding too much noise, and being able to see a little bit of beyond the sidewalk. I have three pretty big IR projectors covering the width of the sidewalk.

You see I have gain and exposure compensation both down to 30. Is it better to increase one versus the other for best image clarity and avoiding ghosting? I used to have both at 50, but I felt the image quality was not great. I've played with it so much I sometimes make it worse.

20221020214726.jpgScreenshot_20221020-214910_Chrome.jpgScreenshot_20221020-214920_Chrome.jpg
 
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what does a shutter range of .25-16.0 yield?
 
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As above try setting the shutter to 16ms, you really don’t have enough light so either you add some light or go with a slightly slower shutter speed.
 
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With a tracking PTZ, you can make the shutter slower since the camera is moving with the object. You could probably bump the shutter to 20ms and improve the image overall and still get clean captures.

Running iris at 100 is also problematic - make it no more than 70.

You should drop NR down as that is contributing to your ghosting with a tracking PTZ. Drop them both to 40.

You should be able to run 40-50 gain without an issue, especially since you have supplemental IR.

You need to get off the default 50 for the brightness, etc. page. Have contrast be 7 higher than brightness. Drop sharpness to 45.

Exposure Compensation is one of those what does it do LOL. Not really, but most of us don't see it do anything...why... because in manual mode exposure that most of us run, compensation exposure doesn't run; it only works in auto / shutter priority mode. It basically is another function to brighten the image based on available light if you run auto or shutter priority (it is moving gain up and down).
 
This is very helpful, I'll try tonight. Out of curiosity, why does iris being fully open cause issues?

With a tracking PTZ, you can make the shutter slower since the camera is moving with the object. You could probably bump the shutter to 20ms and improve the image overall and still get clean captures.

Running iris at 100 is also problematic - make it no more than 70.

You should drop NR down as that is contributing to your ghosting with a tracking PTZ. Drop them both to 40.

You should be able to run 40-50 gain without an issue, especially since you have supplemental IR.

You need to get off the default 50 for the brightness, etc. page. Have contrast be 7 higher than brightness. Drop sharpness to 45.

Exposure Compensation is one of those what does it do LOL. Not really, but most of us don't see it do anything...why... because in manual mode exposure that most of us run, compensation exposure doesn't run; it only works in auto / shutter priority mode. It basically is another function to brighten the image based on available light if you run auto or shutter priority (it is moving gain up and down).
 
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This is all digital processing, so it really isn't an iris like with a real camera, so making the iris 100 means the firmware is making adjustments via gain...too much gain...too much ghosting. Plus it will narrow the focus zone in the process.

Because of all the digital processing, it is best to not go to the extremes of any parameters. You play with these enough you can literally see that changing a parameter 1 number can completely change the image. Like in my field of view, gain at 69 is ok, but 70 and it goes to crap.