Using Mobius with LED lights or headlights

[Hilts]

Does anyone have any experience of using their Mobius with LED lights in their homes or in a car with full LED headlights? If so are there any issues with flickering /flashing?

 

[GJHS]

I have used it with a two LED bike light (1000 lumens) when caving without issue

http://dashcamtalk.com/forum/threads/mobius-down-under-literally.4757/

 

[Dashmellow]

Digital video cameras including the Mobius can have trouble with certain LED lights but it's not the fault of the camera. Some LED lights are used at full power and these remain on constantly but in many LED applications the emitter drivers use PWM (Pulse Width Modulation) as a regulation method to adjust their brightness (dimming) and/or to prolong their useful life. Pulse Width Modulation with regards to LEDs means that the LEDs will be pulsed or strobed at a rate so fast that the eye will see the light as being constantly on. In fact it is not. The camera can detect this high speed strobing and the video it records of these lights can appear as flashing. Some LED flashlights also use PWM for example, especially when they have brightness levels. If you wave one of these flashlights in front of you vigorously if the brightness is turned down you can often see the strobing effect of PWM. You may notice in some video you capture with a Mobius that certain LED traffic lights, road signage and car tail lights are flickering and what you are seeing is PWM.

 

[leftlanehog]

+1 on the PWM issue.

PWM is usually on lower modes/dimming but not present on "high mode".

Flashlights/things that use LED are moving to constant current(no flickering, but in some cases there is a tint shift at lower levels), that is if the company is up to date and evolving.

 

[niko]

@Hilts, please clarify meaning of "flickering issue".

I am afraid you probably pointing out same issue some Mobius users had with 5-seris FW ( was it 0.53 or other FW, I dont remember any more ), but yesterday I finally upgraded from 1.13 to 1.20 and regretted it. I had same flickering issue with 1.20 which I did not had with earlier FW. They say - dont' fix if it are not broken . I think I go back to my favourite v0.59

 

[Hilts]

I have used it with a two LED bike light (1000 lumens) when caving without issue
http://dashcamtalk.com/forum/threads/mobius-down-under-literally.4757/

....You may notice in some video you capture with a Mobius that certain LED traffic lights, road signage and car tail lights are flickering and what you are seeing is PWM.

+1 on the PWM issue. PWM is usually on lower modes/dimming but not present on "high mode".
Flashlights/things that use LED are moving to constant current(no flickering, but in some cases there is a tint shift at lower levels), that is if the company is up to date and evolving.

@Hilts, please clarify meaning of "flickering issue".

I am afraid you probably pointing out same issue some Mobius users had with 5-seris FW ( was it 0.53 or other FW, I dont remember any more ), but yesterday I finally upgraded from 1.13 to 1.20 and regretted it. I had same flickering issue with 1.20 which I did not had with earlier FW. They say - dont' fix if it are not broken . I think I go back to my favourite v0.59

@GJHS Thanks, I've seen this video of yours. Do you do that for fun?? I've had enough of tunnelling to want to avoid them in my free time!!

@Dashmellow, this is exactly what I've seen on a car with LED taillights. I'm thinking of going for LED lighting throughout my house and also looking at replacing my car with one with full LED headlights.... hmmm could make using the Mobius at night a non-starter!!

@leftlanehog, any ideas if household lighting uses PWM or LED car headlights for that matter?

@niko, I'm looking at going for LED bulbs throughout the house and also replacing my car (I'm currently considering the new Seat Leon, which has the option of full LED lights)... I've seen LED taillight flicker, so I suspected going for full LED headlight may not be a good idea re. Dash camera recording at night!!
I've also experienced the flickering light issue firsthand when using FW 1.20 as discussed in Mobius 1.20 Firmware Discussion Thread e.g.,

Best of luck with it!
I suspect that once you start looking at scenes with no street lights (oncoming cars, signs, etc.) and lit areas (with downward projection street lights) that you'll notice the slight flickering with FW 1.20. It's not bad, but not as stable as with FW 1.13....

It does seem that my Lens B is less affected than those using Lens A. Clearly this is nothing to do with LED lighting though!

 

[niko]

I don't think full LED lights can change anything ( maybe I am wrong ).
I do have Xenon / HID driving lights + same set of Fog lights + powerful Osram DRL 5w each, also side bulbs Osram LED 4w each, - of course they are not effective as much as main light LED, but I assume the issue of Mobius flickering is in FW.

I have added video HERE

 

[Hilts]

@niko, thanks for the video. That does appear to be FW related, which is a little off-track from this thread...
I was trying to find out what experience/knowledge there was out there specifically in relation to LED lights (having seen rear LED's flickering on footage recently).

 

[leftlanehog]

No idea about headlights....I didn't know they even make "DOT Legal" LED headlights. My guess is that there will not be any flickering caught by camera. I'd buy them at a place that you can return them if needed.

House lights- I only have (2) LED light bulbs for the house(Futlight brand, and uses PWM for dimming...annoying if I try to notice, but, if I am filming something in the house the lights are on full power anyway to get better vid quality). On High, they don't flicker(because they are not using PWM to dim), but on the medium/low modes there is visible flicker with a camera and easily seen with a fan test.

You can use a normal fan to detect if the circuit regulating the power to the LED is PWM controlled. (or you can wave your hand/fingers fast to notice it...some people are more sensitive to PWM than others)


Bottom line- if the LED headlight/house bulb/flashlight/etc uses PWM you will most likely notice it when light is on lower modes, but, won't notice it on high-cause it's not using PWM on high mode.

PS- some PWM rates are pretty high in frequency that cannot be detected with human eye(even with fan or "finger test") not sure how fast the PWM frequency would have to be to be "invisible" to a camera tho.

 

[niko]

@niko, thanks for the video. That does appear to be FW related, which is a little off-track from this discussion.
I was trying to find out what experience/knowledge there was out there specifically in relation to LED lights (having seen rear LED's flickering on footage recently).

Except Mobius v1.20, I never had a flickering issue with any of the dashcams if driving behind car with high power numberplates LED or towards moving car with fully loaded LED / Xenon like mine below
So I dont think your new Seat Leon with full LED will be an issue. It's more likely dashcam FW issue.

 

[leftlanehog]

if it's "dimmable" and from China(not an insult, the Chinese make great products depending on who they are manufacturing for/specs) and cheap in price...it uses PWM.

 

[niko]

if it's "dimmable" and from China(not an insult, the Chinese make great products depending on who they are manufacturing for/specs) and cheap in price...it uses PWM.

I also had cheap chinese ones at the beginning, but then went over to much more expencive OEM Taiwanese Magotan DRL which uses Osram LED with full certs.

Mine are from Winpower

They are OEM of LED / DRL lights for many cars.

I am sure Seat uses Original fully certified LED-s.

 

[Hilts]

@leftlanehog - Thank you, looks like going for LED around the house won't be an issue!

@niko - I see your point re. FW. I can't remember which one it was, as I changed from FW 1.13 to FW 1.20 and back to FW 1.13 again recently! Also looks like I shouldn't be worried about full LED headlights either! Thank you.

 

[niko]

@leftlanehog - Thank you, looks like going for LED around the house won't be an issue!

@niko - I see your point re. FW. I can't remember which one it was, as I changed from FW 1.13 to FW 1.20 and back to FW 1.13 again recently! Also looks like I shouldn't be worried about full LED headlights either! Thank you.

I remember when with V0.53 many had same flickering issue, - but I didn't had it.
But now many don't have flickering issue with v1.20, but you, me and few others have.
So it's kinda lottery I guess, but its good that Mobius has many other alternative FW-s we can play around with. Thats why I do like Mobius.

 

[Hilts]

I remember when with V0.53 many had same flickering issue, - but I didn't had it.
But now many don't have flickering issue with v1.20, but you, me and few others have.
So it's kinda lottery I guess, but its good that Mobius has many other alternative FW-s we can play around with. Thats why I do like Mobius.

Agreed, the support for & development of Mobius is incredible!

 

[Dashmellow]

There seems to be some confusion in this thread about the concept of "flickering" with the Mobius. There are two separate issues being discussed here. One is a firmware problem of a "flashing" within the FOV at night with v.1.20 and the other is the nature of LEDs captured via digital video when they are regulated with Pulse-Width Modulation. The flashing problem at night with the newest Mobius firmware version as seen in the video Niko posted has nothing to do with LEDs.

I thought it might be useful to post some examples of PWM as I referred to it in my initial reply to Hilts' topic. With PWM what appears to the eye as steady always on illumination will be captured as blinking.

Usually, it is just the LED lamps themselves that appear to be blinking but it can also be the area illuminated by them as seen in this car interior video. LED video screens also use PWM and you will notice the monitor on the dashboard is blinking as well. PWM is always set at different frequencies and this changes the apparent speed of the blinking.

 

[niko]

There seems to be some confusion in this thread about the concept of "flickering" with the Mobius. There are two separate issues being discussed here. One is a firmware problem of a "flashing" within the FOV at night with v.1.20 and the other is the nature of LEDs captured via digital video when they are regulated with Pulse-Width Modulation. The flashing problem at night with the newest Mobius firmware version as seen in the video Niko posted has nothing to do with LEDs.

I thought it might be useful to post some examples of PWM as I referred to it in my initial reply to Hilts' topic. With PWM what appears to the eye as steady always on illumination will be captured as blinking.

Usually, it is just the LED lamps themselves that appear to be blinking but it can also be the area illuminated by them as seen in this car interior video. LED video monitors also use PWM and you will notice the monitor inside the car is blinking as well. PWM is always set at different frequencies and this changes to apparent speed of the blinking.

You totally right, tail light LEDs are always flashing if check dashcam videos and many front LED lights as well, but not all - it's all about PWM as you mentioned.

 

[Hilts]

There seems to be some confusion in this thread about the concept of "flickering" with the Mobius. There are two separate issues being discussed here. One is a firmware problem of a "flashing" within the FOV at night with v.1.20 and the other is the nature of LEDs captured via digital video when they are regulated with Pulse-Width Modulation. The flashing problem at night with the newest Mobius firmware version as seen in the video Niko posted has nothing to do with LEDs.

I thought it might be useful to post some examples of PWM as I referred to it in my initial reply to Hilts' topic. With PWM what appears to the eye as steady always on illumination will be captured as blinking.

Usually, it is just the LED lamps themselves that appear to be blinking but it can also be the area illuminated by them as seen in this car interior video. LED video screens also use PWM and you will notice the monitor on the dashboard is blinking as well. PWM is always set at different frequencies and this changes the apparent speed of the blinking.

@Dashmellow - Thanks for pulling it back on thread! The second video was precisely the sort of thing I'd seen (on a VW Golf R I was following in traffic).
I'll have to keep my eyes peeled for a car with full LED front headlights to see what they look like on footage. They are very rare at the moment, so this could take some time....

 

[niko]

@Dashmellow - Thanks for pulling it back on thread! The second video was precisely the sort of thing I'd seen (on a VW Golf R I was following in traffic).
I'll have to keep my eyes peeled for a car with full LED front headlights to see what they look like on footage. They are very rare at the moment, so this could take some time....

As per "pulling back to thread" ?, then I understood your questions on the first place was about you want to buy a Seat Leon and considering full LED lights of your car, so there was your concern if those LED lights on YOUR Car would affect recording ( causing flickering ) on camera installed on YOUR car. So thats why my replay-s were not related to PWN. Because your car LED lights will not have affect on video recording causing flickering.
So, here was a little bit confusion about what exactly did you mean about your concern to buy LED lights or not to buy , or maybe because my English is not a native language, so I confused myself ? , - if so, - then sorry, I hope to learn more English
Anyway, we discussed both scenarios here, so I guess you have now more clear picture.

@niko, I'm looking at going for LED bulbs throughout the house and also replacing my car (I'm currently considering the new Seat Leon, which has the option of full LED lights)... I've seen LED taillight flicker, so I suspected going for full LED headlight may not be a good idea re. Dash camera recording at night!!
I've also experienced the flickering light issue firsthand when using FW 1.20 as discussed in Mobius 1.20 Firmware Discussion Thread e.g.,
It does seem that my Lens B is less affected than those using Lens A. Clearly this is nothing to do with LED lighting though![/QUOTE]

 

[Hilts]

@niko, You'd initally asked what I'd meant by flickering and mentioned the issues you'd had with FW 1.20, hence why I directed you towards the Mobius 1.20 Firmware Discussion Thread.

I knew nothing about LED lights, but had noticed the flickering on the rear lights of the VW Golf I mentioned above, which got me thinking about LED lighting.
I can assure that your and others comments/information are much appreciated!