Reflective tools to calibrate LPR camera focus at night?

[blocksog]

I have the Z12E S2 dedicated to license plates. It has manual scheduling for Day and Night modes, both with manual focus. The frame you see in the picture is maybe 170 ft away, not sure. Despite the manual focus, it starts to lose focus every few days, not sure why, maybe because it shakes due to my bad mount on the house siding instead of any wood support. Anyway, I need to check where its focus it at night sometimes, but is pitch black due to LPR settings (1/1000 shutter). I am thinking to put something reflective on that curb, but not sure what might work. I already placed a foot or so of yellow reflective tape (see the curb carefully) but is totally useless at night. I am thinking to put reflective stud markers like these, but not sure if that will work. Note that the curb there is not my property, it's a neighbor. I cannot put things that are two visible or stick out much. Needs to be something I can tape/glue on the curb and people don't notice during the day. Has anyone done this before? Any ideas?

 

[bigredfish]

Two things come to mind

1- I used some street commercial grade white reflective tape right in the middle of the street
2- With the newer ones holding focus better you should use MANUAL focus. Its a bit more hassle to setup but it works well.
3- And when adjusting set the "Step" to 1, it defaults to 20 and leaves a far wider zone of focus.

At 120ft I found that just a few steps like 5 made the difference between great focus and meh focus

 

[The Automation Guy]

I am curious to know if anyone has a solution. My Z12E (an older model) also will loose focus as time goes on. I have the service set up to manually change it from day to night and back each day and it is suppose to reset the focus to a manual number as well. Still, over time the focus gets worse (in both day and night mode).

 

[bigredfish]

Are you set using Manual Focus?

I run a schedule and make it change at least 45 min before sunset and 45 min after sunrise for 8 years now.
Having tried all the tricks over the years, I find this one to be 100% reliable. That or leaving it in B&W 24/7

Rarely have a problem and dont even bother changing the times but maybe 1-2x p/year.

Even the utility you use still allows it to try and focus when there really isnt enough light to do it

 

[blocksog]

Two things come to mind

1- I used some street commercial grade white reflective tape right in the middle of the street
2- With the newer ones holding focus better you should use MANUAL focus. Its a bit more hassle to setup but it works well.
3- And when adjusting set the "Step" to 1, it defaults to 20 and leaves a far wider zone of focus.

At 120ft I found that just a few steps like 5 made the difference between great focus and meh focus

For your points 2 and 3, I already use manual focus 24/7. And yes, I use the camera GUI to fix the focus and play with the Steps to fine tune. My question is basically what reflective tape or stud has worked for you or others here.

@The Automation Guy , looks like we have the same problem. Is your camera well fixed with screws? Mine wobbles in wind conditions and I thought that causes the lens to shift inside. But if yours is sturdy, there might be another reason.

 

[blocksog]

Are you set using Manual Focus?

I run a schedule and make it change at least 45 min before sunset and 45 min after sunrise for 8 years now.
Having tried all the tricks over the years, I find this one to be 100% reliable. That or leaving it in B&W 24/7

Rarely have a problem and dont even bother changing the times but maybe 1-2x p/year.

Even the utility you use still allows it to try and focus when there really isnt enough light to do it


View attachment 226087 View attachment 226086 View attachment 226085

Not sure I follow. You have manual focus at day and night, right? Then the focus should never ever change because there is no profile with auto focus. This is what I was hoping at least. Or are you running Night at manual and Day at Auto?

 

[bigredfish]

Both are manual.

There is a focus difference between day color and night IR

I run the schedule as a backup to those manual settings because I had run it for years that way before switching to manual.

Mine just works don’t know what to tell ya

 

[bigredfish]

This is the type of tape I used but that was 7 years ago

https://www.amazon.com/RPT-750-White-Reflective-Pavement-Marking/dp/B09X8MKHJ1/

 

[blocksog]

Both are manual.

There is a focus difference between day color and night IR

I run the schedule as a backup to those manual settings because I had run it for years that way before switching to manual.

Mine just works don’t know what to tell ya

I guess that's what is killing my experience. I thought the focus is always the same, but as soon as I switch the camera to night mode it is blurry as fuck. Then I tune it for night time with a license plate and next day I find it blurry during day. If focus has to be different between daytime and IR/nighttime, I have a question:

Since there's no manual number for focus on any profile, how are you telling the camera to switch to night focus time? Are you putting there a minute of autofocus profile before switching to fully night profile with manual focus?

 

[wittaj]

Yep for some field of view the focus can be different day and night. One of mine is a 10 point swing.

No auto focus. Set focus to manual and during the day set the focus and then at night in night profile stop a car in the middle of the field of view and get a night focus. Trying to set a night focus during the day can be problematic.

As you hover over the slider a number should pop up with the focus number.

If you don't get this, then it is a browser issue and that could be contributing to the problem.

 

[bigredfish]

Go to daytime profile set to Manual. switch to zoom/focus tab. Use the zoom control (typically don’t touch the focus slider) and with a parked car or plate held by wife, set zoom to clear image using the 1 speed/step dropdown.
Go back to profile and Save

Repeat in night profile at night.

The number for focus and zoom can be seen by hovering mouse over the slider

Yes IR has a different focal point than color

When the schedule goes to night, I have many different settings for night vs day, it also switches to the night zoom/focus

 

[blocksog]

I am going to try this later. Fyi, I have S2 and gui looks different from yours. The only place I can set the focus is the Live view tab, I think.

 

[wittaj]

I have both versions and you can set it in multiple locations. I prefer the live view because it is larger and the number will show on the slider when you hover the mouse over it.

 

[samplenhold]

I have two Z12E's for LPR, LPR-E and LPR-W. They are running the same firmware version. I use the Day/Night utility to switch between day and night. Both set to manual focus. Both cams use the SAME focus value for day and night. Weird, but they do. No difference between day and IR focus.

When we lose power to those cams, LPR-W ALWAYS reverts back to 1601 focus. I have to reset it for both day and night back to 1610. LPR-E always keeps the same focus after a power outage (1450 focus). Weird.

 

[bigredfish]

I think ambient light plays a factor.

I have one at the old HOA culdesac that has the same day/night values too, but there’s a very bright streetlight almost perfectly placed that provides a ton of white light to the capture area

 

[samplenhold]

Both of my LPR cams have a streetlight right there.

 

[blocksog]

I have both versions and you can set it in multiple locations. I prefer the live view because it is larger and the number will show on the slider when you hover the mouse over it.

Where are the multiple places to set the focus? I go to Camera settings, switch to Night profile, and then go to Live view to change the focus, but when I go to Live, the profile changes back to the scheduled Day profile. I can wait for the Night schedule to kick in, but you mention you can set the focus at various places, maybe at the Camera settings itself so the profile does not switch back to Day?

 

[wittaj]

That is why we said you have to set the focus in the time frame of the profile you are wanting to set (set day focus while day profile is active and night profile when it is night).




I was mistaken, for the Z12E-S2 it is only in Live view that you can change those settings.

 

[blocksog]

Thanks. Yes, yours screenshot matches mine, focus is set only in Live view. I am still surprised that focus setting is baked in the schedule profile. Dahua and Empiretech can do a better job to convey this, like put a slider to set that manual focus in the profile view itself:

 

[wittaj]

It had its own tab in the older GUI, but as you can see from above, the image is kinda small, so I always did mine on the larger live view.