How important are good headlights for good dashcam performance at night?

[TonyM]

Since we're here, we can look at another comparison between number plate capture at night on 4K HDR vs 1080p telephoto - all 3 frames are at the same moment in time for direct comparison.

You can see that when viewed at 100%, the A139 Pro 4K has almost the same magnification as the 6mm telephoto 1080p camera. Accordingly, the 8mm 1080p camera has a bit more magnification, and is the only one where we can read "York Van Centre" on the back of the ISUZU truck, or "follow A64" on the yellow sign.

The metering seems to be affected by what proportion of the frame is filled by bright objects (headlights & reflections), so when I'm up close behind other cars the telephoto cameras record a darker exposure, which is actually useful to avoid clipping highlights. The shorter, darker exposure still cannot match the A139 Pro HDR though.

NOTE - Ignore the "HDR ON" text in the telephoto frames. That relates only to the main 5MP A139 camera where I did have HDR turned on. HDR is not a feature of the IMX291 remote cameras.

A139 Pro, 4K STARVIS 2 HDR (wide angle) (2x crop, i.e. 100% at 1920x1080)


1080p IMX291 STARVIS 1 (6mm F1.2)


1080p IMX291 STARVIS 1 (8mm F1.8)

 

[Nigel]

or "follow A64" on the yellow sign.

The A139 Pro is remarkably close to the 8mm, and clearly better than the 6mm!

Definitely loses on "York Van Centre", it has compromised the exposure to get more detail in the shadows, but it clearly wins on the oncoming plate.

Are there any circumstances where the telephotos are clearly worth having, given that you have an A139 Pro pointing in the same direction?
Maybe you need a 12mm...

 

[Harsh]

On this occasion the 4K HDR out-performed both my telephoto cameras, when considering number plate capture only. 100% crops from all 3 camera below:

A139 Pro, 4K STARVIS 2 HDR (wide angle)
View attachment 62911

1080p IMX291 STARVIS 1 (6mm F1.2)
View attachment 62912

1080p IMX291 STARVIS 1 (8mm F1.8)
View attachment 62913

Since we're here, we can look at another comparison between number plate capture at night on 4K HDR vs 1080p telephoto - all 3 frames are at the same moment in time for direct comparison.

You can see that when viewed at 100%, the A139 Pro 4K has almost the same magnification as the 6mm telephoto 1080p camera. Accordingly, the 8mm 1080p camera has a bit more magnification, and is the only one where we can read "York Van Centre" on the back of the ISUZU truck, or "follow A64" on the yellow sign.

The metering seems to be affected by what proportion of the frame is filled by bright objects (headlights & reflections), so when I'm up close behind other cars the telephoto cameras record a darker exposure, which is actually useful to avoid clipping highlights. The shorter, darker exposure still cannot match the A139 Pro HDR though.

NOTE - Ignore the "HDR ON" text in the telephoto frames. That relates only to the main 5MP A139 camera where I did have HDR turned on. HDR is not a feature of the IMX291 remote cameras.

A139 Pro, 4K STARVIS 2 HDR (wide angle) (2x crop, i.e. 100% at 1920x1080)
View attachment 62914

1080p IMX291 STARVIS 1 (6mm F1.2)
View attachment 62915

1080p IMX291 STARVIS 1 (8mm F1.8)
View attachment 62916

Quite surprised the 8mm didn't catch that. The metering doesn't look ideal for telephoto use.

It's probably the 12mm's reach + HIDs in my setup's case.

 

[TonyM]

Are there any circumstances where the telephotos are clearly worth having, given that you have an A139 Pro pointing in the same direction?

I'm still figuring that out. I think the telephoto fares better in dull, overcast conditions where the number plates are not illuminated by headlights.

I have plans to upgrade the 8mm telephoto with a 1440p base camera.

 

[kamkar]

@Panzer Platform when you said you drive a crown vic, my mind played the scene from the blues brothers movie.

 

[Nigel]

I'm still figuring that out. I think the telephoto fares better in dull, overcast conditions where the number plates are not illuminated by headlights.

I have plans to upgrade the 8mm telephoto with a 1440p base camera.

A 1440 will give you more "Telephoto", but at the expense of some dynamic range, and a little extra motion blur. If you are not interested in FoV then I'm not convinced it will win over an upgrade to 12mm. Would be interesting to see though...

in dull, overcast conditions where the number plates are not illuminated by headlights.

 

[TonyM]

I popped into Halfords just to see what they had in stock for a headlight upgrade for my car. Their system recommended these H11 bulbs, in 100%, 150% or 200% variants.



I don't mind buying bulbs online, but I admit that I don't have a clue how to fit them. So a physical store that offers fitting is appealing to me.

 

[Harsh]

New bulbs will be brighter but won't change spread or cut-off. Need to adjust the cut-off using a screwdriver or change the projectors. Since it's an older car, I'd recommend a HID projector retrofit. Check out Morimoto.

 

[Kremmen]

Unfortunately, in the UK, HID retrofit is illegal and means the car will fail the annual compulsory safety check (MOT) making insurance invalid

 

[TonyM]

Unfortunately, in the UK, HID retrofit is illegal and means the car will fail the annual compulsory safety check (MOT) making insurance invalid

Thanks. That explains why they're not generally on sale here. I'm happy to buy the brightest bulbs I'm allowed to use, but only if my local garage will fit them and confirm they're legally compliant.

 

[Harsh]

 

[Nigel]

Their system recommended these H11 bulbs,

H11s are not projector bulbs, and from the previous discussion, you currently have HID projector bulbs, so the H11s would not fit.

I still suspect the problem is more to do with beam pattern than poor bulbs, but I don't know, maybe worth a direct replacement of your current bulbs with fresh new ones, but that is unlikely to change the beam pattern.

 

[Harsh]

H11s are not projector bulbs, and from the previous discussion, you currently have HID projector bulbs, so the H11s would not fit.

HID Projector bulbs are available for all socket types - H1, H3, H4, H7, H11, HB3, HB4, 9005, D2S etc.

@TonyM New bulbs and a bit of horizontal adjustment using a screwdriver should suffice. Even if the reflective coating on the bowl of the projector has degraded, the bulb change and adjustment should make a noticeable difference.

 

[Nigel]

HID Projector bulbs are available for all socket types - H1, H3, H4, H7, H11, HB3, HB4, 9005, D2S etc.

I think that would be illegal here, I do not think that cars are manufactured with H11 projector bulbs?

 

[Kremmen]

Yes, in the UK, HID systems must be self levelling and have washers.

If they are not OEM factory fit then the risk of MOT fail is high.

 

[TonyM]

I know I have self levelling. That just cost me a few hundred pounds to fix at the last MOT.

As to the type, I'm rather confused now.

Those H11 are what come up when I put my number plate into the database to find compatible car parts.

 

[Harsh]

I think that would be illegal here, I do not think that cars are manufactured with H11 projector bulbs?

Tony's Mazda 6 comes with H11 HID bulbs. Hence I suggested changing the bulbs and playing with the horizontal adjustment. The current setup is aimed too low.

Best would be he takes it to the service centre for new bulbs and plays with the alignment or ask them to help him with the adjustment.

 

[TonyM]

OK, I've read the manual, checked the specs and watched some videos. I feel more informed now, thanks to people here too. I now understand that Xenon and HID are the same thing!

So, my car has Xenon HID projector headlights with auto-levelling and Adaptive Front Lighting, which appears to use the same 35W D2S bulb for both low and main beam.



It seems as though these should be giving me much better performance, so something is not right.

 

[TonyM]

According to the Sylvania bulb guide the 2010 Mazda 6 uses H7 halogen bulbs, or an optional HID D2S. If you had the optional HID’s I don’t think you would be complaining about light output, (unless both HID’s have malfunctioned).

I do have the optional, factory-fitted HID D2S. But the light output is not very good.

 

[Nigel]

Could be the bulbs, could be the reflector, could be a dirty lens.

Taking a bulb out might help to identify the problem. If you do then be careful not to touch the glass of the bulb.