Optimize Shutter Speeds

105437

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Should I leave Gamma at 50?
 

wittaj

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Many of us have found H264 to be a better picture.

When I show two clips to family members that know nothing about H264 or H265 and ask them which video clip looks better, they all say H264.

Between that and literally only a few minutes of savings per day difference, I go with H264.

As always YMMV.
 

Mike A.

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As above, gamma can be useful for fine tuning. The way that I typically use it is to get brightness and contrast set as best I can first. Then adjust gamma a little to try to tweak it marginally better. Maybe go back and readjust brightness/contrast slightly in response. Maybe think of it as an overall averaging of brighter areas/darker areas. i.e., You can see a little more in darker areas, not as much blowout in the brighter areas.

Like other settings, it's a balancing thing. Too much and the image will have a more washed out/soft look and you'll lose some of the contrast and perceived sharpness that you want.
 
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user8963

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i would test if you have still details on the face of a walking person..

with higher gamma values the overall image looks brighter, but somehow details on faces get washed out when IR light is used and the object is near the camera .. its not really overexposed but somehow like that.

if this is the case you should try a lower gamma value and maybe add some shutter time (10ms).. i know that dark images looks awful when watching live stream but when it comes to identify a person later on footage you might be better with darker image.

also you should test sunrise/sunset times.. with high gamma value and too much light you might also have bad image
 

user8963

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Here an example , shutter speed and gain was the same (around 30min after sunrise), only gamma and exposure comp (still no idea what exactly is done by this setting) is lowered. roughly the same time (15minutes difference).
yes the first is a little bit blurred because i was to stupid to get a frame with more sharpness back then :D

i think this is what @Mike A. mention with "soft/washed out"

(its not the same person)
gamma1.jpggamma2.jpg
 
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user8963

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thanks !
its 5442-ze zoomed to around 8-10mm (not sure about the slider, but its not at the end) , mounted at 2.1 meter height.
the captured part of the walk way is only 1.5 meter, but it is able to get ANY face at day and night
i run it at 20frames because i want to have as many frames as possible at reasonable storage/bandwidth.

i learned when it comes to this sharp face pictures at short distance even the slightest movement can worse the image, so better have more frames.

i tried the same what i read here from LPR and adopt it on face , but LPR doesnt need so much frames because its more easy to read a number than a detail of a face.

also the zoom gives some security, because if the person sees the camera, its to late to hide the face
 
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wittaj

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It is a great example of what I preach probably more than anyone lol - that I like more zoom and you can almost not have too much zoom.

Most people would opt for the 2.8mm at 1.5 meter, but they would not be as crisp and large as that.
 

user8963

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But it took me a bit to get it like this, at first i was shocked how bad the image looked at sunrise time in B/W mode... the exposure comp setting has huge impact on this... so needed to watch footage at any light change i could not control ;)
I turned gamma/exposure comp on most camera down ... it only gives you a fake look of brightness and steals you the details you want..
only on the overview cameras its helpful because you see more ;)
 

Mike A.

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i think this is what @Mike A. mention with "soft/washed out"
Yes. Good example of way too much. Everything averages down to "meh" and you lose the details from contrast. Even if you darken it, it will just be washed out darker.

It is useful though in some cases. e.g., For what you were saying about IR blowing out faces. I have a 5231 that where it's installed is terrible for that ("SmartIR" isn't very). If I balance down brightness (which has a much greater such effect) some against a touch more gamma, I can get a little brighter image without that at the same shutter and keep a little more detail in darker areas vs just all jet black. And in some cases it can help to neutralize some of the vibrating pixel effect that you can get in some cams/scenes when you push things a little. I suppose that it minimizes the contrast between the pixels and gives a little cleaner image without having to move NR back up. But, as always, it's a case-by-case thing and better done in small increments as you said for fine tuning.

Always interesting to me how much difference there can be between best settings even for two of the same cams installed in an area with the same overall level of light but on different scenes. I have two different 5442s, two different sets of image adjustments. Or between two very similar cams like a 5231 and 2231 looking at the same area from different angles. My best settings aren't anywhere even close for those. Kind of pointless to ask about best settings beyond broad generalities.
 
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JonSnow

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When setting the shutter to 1/120 for example (not range), does that mean minimum or is it fixed to only 1/120?
Is a lower grain value better, 0-40 is better than 0-60?

Manual Night Color:
Shutter: 0-16.66, Grain 0-70 is a bit grainy but not blurry.
Shutter Priority 16.66 is not grainy and not that blurry but still need to test.

Manual B/W:
Shutter: 0-8.3, Grain 0-50 is a bit grainy but not blurry.
Shutter Priority 8.3 is untested.

I find the color images are not as clear as the B/W images but overall prefer the color images.
 
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wittaj

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If you set it at 1/120 that means that is the shutter speed regardless of light conditions.

A range of say 0 to 16.67 means if there is light available to go to a faster shutter, then it will.

Having gain as low as possible is ideal.
 

Mike A.

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Take shutter a step faster. Readjust picture settings to compensate a little for what will be a darker image.

Not sure how you have IR set. If on auto/SmartIR, then also can a try putting on manual and maybe get more light (but probably will blow out faces when they get close).

Overall image looks pretty good to me. If you can get that same look with faster shutter, you'll be good.

How do you have video stream set up? 15 FPS? 20? Bitrate? Variable/constant?
 
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user8963

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you can try gamma to 30-45 , contrast 55 , shutter 6.67, but with darker image may lose details far away..
you can also try to turn down gain to 35-40 and maybe more shutter time...
as shown above in my 2 screenshots shutter/gain is not the (only) problem with B/W mode and IR light.

all in all in my opinion the image is improved
post video tab as mention above, maybe there could be some improvement..

but ... as discussed a few posts above.. it is impossible to get a clear face shot with a wide view camera. if you want photo quality you need more zoom .. even more pixels shouldnt give you the same result as more zoom...
 
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105437

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Take shutter a step faster. Readjust picture settings to compensate a little for what will be a darker image.

Not sure how you have IR set. If on auto/SmartIR, then also can a try putting on manual and maybe get more light (but probably will blow out faces when they get close).

Overall image looks pretty good to me. If you can get that same look with faster shutter, you'll be good.

How do you have video stream set up? 15 FPS? 20? Bitrate? Variable/constant?
Thanks @Mike A. I will bump the shutter to 1/200 (5.00 ms). I'm using an external IR with the camera IR turned off. I have increased Brightness to 60 from 50 and Gamma to 60 from 55. I also bumped the upper end of Gain to 60 from 50. Video settings below as well. We'll see how it looks tonight.

1637417422009.png
1637417569465.png
1637417688140.png
 

Mike A.

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Try it. See how it looks/goes.

Only thing that you didn't really get all that great in that one was due to motion. If the fox were walking more slowly or stopped and sat there for a second you'd be good. Faster shutter should help that some but, as above, you'll need to try to get back close to where you are overall once you change that.

Bitrate is more than enough for 1080 but leave that as is for now. CBR good. Try taking it up to 20 fps. As @user8963 said earlier that will help get more frames for better chance to capture quick movements like that.

Maybe take sharpness down a hair too. Hard to judge that between different cams and I don't recall how much effect for each step at night on my 5231. Don't want to make it too soft but that can help a little with noise in motion. Try down -5.

Also it's a 1080 cam so it's only going to get so good as far as details. As above, maybe take the zoom in just a little more to help with that. Every little bit helps a lot. Maybe move the cam down just a bit too. Don't think that you really need to see things at the top of the image quite as much as you have it and that will let you get more as it's closer to the cam.

Depends what you're trying to do too. Someone walking down that road, you'd probably be OK as it was. Running, riding a bike, or getting those little fox legs and head turns in motion clearly or a license plate on a car moving quickly, probably not and probably won't without things looking much different overall.

Too bad you can't ask it to run down the road in the same way again tonight for comparison. Seems like you've got some regular animal traffic though so should have something to compare soon.
 
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