I upped the bit rate to 14000. I will look into the aperture. I like the idea you guys are giving me.
Dahua 4K PTZ DH-SD8A820WA-HNF
- Thread starter Parley
- Start date
I did make a minor change to the aperture. Also while I was in the camera I changed one of the night settings to street lamp. There were maybe 6 choices. Here is a photo from today as I wanted to take a picture of a car coming down the street to see if I could pick up the license plate number at that distance. No way in hell could I to this with the 2MP Hikvison PTZ at this setting. It is the white Toyota with number 6FTW000. I just wished that Dahua had a manual on this camera. Most items are covered with an internet search, but there are others that I do not have a clue as to exactly what they do.
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tech101
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Can you post another video when you have a chance with this new dialed in focus .. At night 
Specially with some movment maybe people moving or cars when you get a chance. Thank you one again The quality is amazing !
Specially with some movment maybe people moving or cars when you get a chance. Thank you one again The quality is amazing !
That is the next area I want to work on some more. It seems that the focus distance is reduced as of last night compared to day time. However in that focus distance the picture is very good. I was watching a man and a woman walk down the street toward the camera and when they entered the focus area they were very clear and I could clearly read the writing on the man's shirt. ID'ing them would be easy. By the way I have the IR lights off if anyone wants to know.Can you post another video when you have a chance with this new dialed in focus .. At night
CCTVCam
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- Sep 25, 2017
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As general photography principle, if you have aperture control, smaller is better in daylight to maximise depth of view (set it on a dull day rather than a bright sunny one or you might find too much gain kicking in on dull days or a picture that is dark) and for night larger is better for light gathering, albeit with the caveat stay as small as you can as each step up reduces the depth of field and thus the range of objects in focus.
Thanks for the info. I played with the settings last night for quite awhile, adjusting them back and forth to see what would happen. I even initialized the lens setting, not sure I should have done that. By the time I finished there was no one out walking that I saw, so no pictures. I will just play with the aperture tonight and see what happens. As of right now I think I have the daytime dialed in. The night time seems to have good focus for maybe 150' or so. Closer in starts to lose focus and further out it from that starts to lose focus. I am having trouble stretching that out. I have the IR shut off, maybe I should give that a try. Usually with the IR on peoples faces do not show up well at all.
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ljw2k
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I usually find DEFAULT values gives you a good indication on what the camera can do. Playing or tweaking settings is all good until you go to far as one setting upsets another.
Rainy out tonight and nobody is out walking around. Here is a still picture of someone getting into there car way down the street. You have to look hard. At this point in time it seems I have to sacrifice up close focus for better focus further out. I can always change the focus for a close in shot but I have other cameras that cover that area.
ljw2k
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ljw2k
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Floodlights on a PIR for better night results in colour or 2mp starlight+ fixed at the focal distance you want.. If it was me and wasn't happy with the picture in forced colour which you are obviously not I would switch to B&W and the in built IR for night time footage.
It looks like you have pretty good street lighting where you live now and I doubt very much if that camera would work well at night in colour especially in a rural suburb. You are not going to get any better results than you have shown already at night in colour from the camera only and think you are asking to much from that particular camera forced to colour in your area.
I would also think it would focus better in B&W with the built in IR enabled.
It looks like you have pretty good street lighting where you live now and I doubt very much if that camera would work well at night in colour especially in a rural suburb. You are not going to get any better results than you have shown already at night in colour from the camera only and think you are asking to much from that particular camera forced to colour in your area.
I would also think it would focus better in B&W with the built in IR enabled.
Thank you for your reply. I will probably leave it pretty much like it is in color and no external lights. Maybe tweak the aperture/iris a little and see if that makes difference. Not sure if I go to 25fps if that would make much of a difference outside of using my more of my storage capacity.
Heck. pretty soon this will be reality on our cameras. Could have added it as an April Fool's feature in Blue Iris
CCTVCam
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I think you're probably not understanding depth of field. Whatever you focus the camera on will be what is in sharp. Beyond that you are relying on Depth of Field to make an object appear sharp. As said, that depends on the aperture. The smaller the aperture the greater the distance away from the focal point appears sharp. The larger the aperture, the smaller the distance away. That's a generalisation. There is a way to maximise depth of field by finding the hyperfocal distance. I'm not a photography guy but you can find guides on it on the internet. Here's one (I didn't have time to read it, so don't know how good it is. But if it's rubbish I'm sure you can use google):
www.photopills.com
Understand as well, maximising depth of field may help render a picture looking sharp front to back but when you come to examine fine detail eg number plates, you may find although the overall picture it looks sharp, when you look visually close up, the detail isn't as sharp as it appears. Ultimately the only way to guarantee sharpness is to have the object you want as the subject, to be the subject of the focus. Beyond that you're relying on the depth of field effect to render objects nearer or further than the focus point sharp.
As previosuly explained at night there are 2 ways to get a lighter picture:
1. Increase the electronic gain - this causes more noise
2. Increase the size of the aperture (go larger), this reduces depth of field and the number of objects from to back in focus.
Depth of Field: The Definitive Photography Guide | PhotoPills
All you need to master depth of field (DoF): meaning, inspiring examples, tips, DoF calculator and charts, DoF app, DoF vs aperture (and sensor size, focal length, subject distance), hyperfocal distance, diffraction, macro photography, circle of confusion, bokeh, preview DoF button – including a...
www.photopills.com
Understand as well, maximising depth of field may help render a picture looking sharp front to back but when you come to examine fine detail eg number plates, you may find although the overall picture it looks sharp, when you look visually close up, the detail isn't as sharp as it appears. Ultimately the only way to guarantee sharpness is to have the object you want as the subject, to be the subject of the focus. Beyond that you're relying on the depth of field effect to render objects nearer or further than the focus point sharp.
As previosuly explained at night there are 2 ways to get a lighter picture:
1. Increase the electronic gain - this causes more noise
2. Increase the size of the aperture (go larger), this reduces depth of field and the number of objects from to back in focus.
Thank you for that answer. I think I have found the happy medium. Picture from a few minutes ago.
What settings did you end up going with? This looks sharp on all four corners, not kidding
Hell if I know, I made so many little tweaks. However I did moved the contrast a tad. From 50 to maybe 58. Not sure on the others without going back through the camera, like the stop sign is now in focus. Most of them are at the factory setting. However to save some memory space I did change the I-frame to 36 and no substreams or audio. I am running at 18FPS.
CCTVCam
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- Sep 25, 2017
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Looks great don't touch it. Maybe you hit the hyperfocal distance by accident. However, for reference for anyone who doesn't manage to hit the sweet spot, if it came down to choosing an area to be sharp, I'd choose the road in front of your house to the corner. corner. Whilst it's great having a sharpness right down the street. Never forget the main purpose of YOUR camera is to protect YOUR property, not your neighbours.