How critical is Lux/Low light ability for night capture?
- Thread starter Bitslizer
- Start date
- Nov 23, 2017
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Here was what I mean by weird focus...
Left is manually focus to sharpest with white reflective tape, notice how blurry the red tape are
middle is manually focus to sharpest for red reflecting tape, notice how white and red are blending together and white is blurrier
right is manually focus on the pavement grain (in IR bw) seems to the red is even more blurry then the first one and the white is just a touch off
But I bet the focus for the left would be the one for to be able to read the plate
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- Nov 23, 2017
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Hope the stickers do the trick, I don't want to have to park my car at that spot every night to focus the camera
Yep, that has been one of the big problems with PTZ cameras for LPR and not able to force a focus like we can a fixed cam.
- Nov 23, 2017
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Dark enough... Here's the auto focus. I can use a onvif script to zoom in (its at max zoom so won't actually zoom more) periodically to force it to re autofocus. Waiting for a car to pass by to check result.... Can't test with my own car until the kids are all to bed
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- Nov 23, 2017
- 467
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- Nov 23, 2017
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Right before the car enter the frame, the headlight actually caused the camera to re autofocus, but it very quickly lock on to the stickers again before the car enter the frame
I'm going to try mounting it to the second story under the eaves as this current location is just for testing as it's got access to my outdoor cat6 run but a lot of angle are blocked by trees and porch posts I can imagine the tree getting worse in the future. Also need to test the south side / T intersection. Luckily there are also light poles in that direction
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- Nov 23, 2017
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- Nov 23, 2017
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continuing my tweak.... can't get it to send snapshot to my Dahua(Flashed Speco) NVR, was able to get it to send to a FTP server, but can only set 1 second interval at the quickest. Making the snapshots hit and miss. Also if multiple car pass by within the same MD session, it will likely only catch Snapshots of the first car.
- Nov 23, 2017
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Pointed it towards the south direction, not the previous T intersection but closer to my house.
No light pole in that direction, but I have some driveway markers, one is by my driveway and the other one is by my curb ... Seem to work the same as the reflective tape
No light pole in that direction, but I have some driveway markers, one is by my driveway and the other one is by my curb ... Seem to work the same as the reflective tape
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That is great. I could get my fixed cam to focus on the reflective tape, but the PTZ struggled and was usually out of focus.
- Nov 23, 2017
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Mine would be blurry and I would have to manual adjust it. But it was a reflective tape around a fire hydrant and not an up and down same plane like yours are, so I think the rounded part was causing different bounce backs and it struggled. My fixed cam had a telephone box nearby with reflective tape that was same plane. I have stakes like you shown, so I will go out and give that a try next to the hydrant.
I didn't spend much time trying to make it work, I was just playing around one night with the PTZ to see if I could make it work as many people have posted having trouble trying to make it work, so I wanted to see how difficult it was.
I didn't spend much time trying to make it work, I was just playing around one night with the PTZ to see if I could make it work as many people have posted having trouble trying to make it work, so I wanted to see how difficult it was.
- Nov 23, 2017
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May have discover something interesting by accident. Focus bracketing to get good focus at night. One reflecting tape marker on the near side curb (stick with sticker.... driveway marker...) and another on the opposite side of the curb along the aim line.... when the camera try to focus it appears to try to do its best to focus on both the near marker and the far marker, resulting in a focus in the middle of the street where we actually wants it. This maybe an alternate to the putting reflecting tape down the middle of the pavement I saw in the other thread.
The left was the light pole far marker, the right is the near side curb stick marker.
I backed off from max zoom to see if 12x if still enough to get legible plate
will see if this give more consistent focus at night
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- Nov 23, 2017
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it is also cutting way down on the false MD alert from the camera re-autofocusing, I was getting alot of false MD spam last night and only 1 or 2 so far tonight (knock on wood)
Flintstone61
Known around here
I have the Jidetech that looks exactly like the Leftek. 2.0 Mexapixel with supposed 20 x optical zoom. It has a nice crisp lens, I was able to use it for a row of parked cars as an LPR, but you had to decide which out of 8 spots you were going to make the focal point. So you cannot read all of them.
When it was in front and I set a focus in the drive way exit and set the shutter to about 500 not 2000 and went IR mode and played around with setting until I could get plates of slow movers in a parking lot. But never a car moving above 15-20 at my particular angle and location. Seems like the motion detection was starting its capture late, and so I had the pretrigger set on 10-15 sec. But it was blurred when i did get a plate. YMMV.
I ended up spending 259 for the Z-12. But i have not installed it yet. SO now I've spent $200 on the Jidetech, and $259 on the z12.
If Granny One-eye in her jalopy cruised by at a slow pace could i get her plate. But ffs she lives here. I screwed around with it for about 10-11 months and put it in a new location as a rear parking lot overwatch.
it was interesting to learn what wittaj said about PTZ's and autofocus issues and plate captures. mighta been why i struggled.
When it was in front and I set a focus in the drive way exit and set the shutter to about 500 not 2000 and went IR mode and played around with setting until I could get plates of slow movers in a parking lot. But never a car moving above 15-20 at my particular angle and location. Seems like the motion detection was starting its capture late, and so I had the pretrigger set on 10-15 sec. But it was blurred when i did get a plate. YMMV.
I ended up spending 259 for the Z-12. But i have not installed it yet. SO now I've spent $200 on the Jidetech, and $259 on the z12.
If Granny One-eye in her jalopy cruised by at a slow pace could i get her plate. But ffs she lives here. I screwed around with it for about 10-11 months and put it in a new location as a rear parking lot overwatch.
it was interesting to learn what wittaj said about PTZ's and autofocus issues and plate captures. mighta been why i struggled.