Any B&W Dashcams? Better night performance

[boilers]

I have more than a few home CCTV/IP-Cams. My old Philips/Magnavox BLACK & WHITE CCTV system has amazing low-light capabilities. Even some of the iPhone 7 rumors thought the dual-camera set-up MIGHT HAVE had one B&W sensor so that Apple COULD HAVE used that better low-light data to fill in the OTHER color camera data, and merge the two for better low-light images.

So, where are the B&W dash cam sensors?

 

[kamkar]

Thats what i want to know too, i always said i would not mind B&W night footage if that mean better low light performance, and maybe even assisted by IR emitters where fog light should be on my car.

BUT ! looking at night footage from my 1080p IP camera it is clear even if aided by IR light the camera still drop down to a low exposure timing.

 

[jokiin]

there's a model by Seezeus that switches to black and white in low light situations, it seems ok but not great, maybe a dedicated black and white system would be better, not sure really

 

[Dashmellow]

The Mobius camera has an option to shoot in B&W. I've done a bit of experimentation with it and it can be effective in improving apparent night time performance. What I learned from this however is just how important color can be in dash cam footage. For example, the color of a particular car is often one of the most important keys to positively identifying it, especially in a challenging lighting situation.

 

[Feitelijk]

As the sensor remains the same, would a postprocessing to B&W by just adding the RBG values not give you the same 'improved' picture?

 

[Dashmellow]

As the sensor remains the same, would a postprocessing to B&W by just adding the RBG values not give you the same 'improved' picture?

Potentially you could adjust the different RGB channels for some enhancement but if the information doesn't exist in the file in the first place there isn't much one can do.

The other thing to consider (that many folks here seem to ignore or not be aware of) is that in a situation involving law enforcement, insurance companies, courts, attorneys, etc., one needs to be able to submit raw un-tampered with original footage.

While it might be useful in some circumstances to enhance footage the goal really needs to be to have the camera provide actionable footage to being with.

 

[Feitelijk]

I agree: the dashcam is geared to make a color picture and will therefor handle the color channels differently. When just adding the values you would get a different result than the cm just trying to get as much light out of a pixel it can itself.

The other thing to consider (than many folks here seem to ignore or not be aware of) is that in a situation involving law enforcement, insurance companies, courts, attorneys, etc., one needs to be able to submit raw un-tampered with original footage.

No problem, the can have the raw footage and the enhanced one.

 

[boilers]

I am clueless as to what makes a good specification on such things.

http://www.analog-eetimes.com/news/13mpixel-low-light-cmos-image-sensor-targets-security-cameras
http://www.e2v.com/news/e2v-introduces-new-onyx-1-3-megapixel-low-light-cmos-image-sensor/

I'd love to see a comparison.

So, I have a 21 year old b&w cctv system and have an IP CAM pointed at its B&W CRT monitor... so the picture quality is BETTER than this image portals. Here is almost same scene from 3 am (night) with porch lights... B&W vs color ...

 

[Dashmellow]

I am clueless as to what makes a good specification on such things.

http://www.analog-eetimes.com/news/13mpixel-low-light-cmos-image-sensor-targets-security-cameras
http://www.e2v.com/news/e2v-introduces-new-onyx-1-3-megapixel-low-light-cmos-image-sensor/

I'd love to see a comparison.

So, I have a 21 year old b&w cctv system and have an IP CAM pointed at its B&W CRT monitor... so the picture quality is BETTER than this image portals. Here is almost same scene from 3 am (night) with porch lights... B&W vs color ...

It is difficult to compare low light performance between some of the newer CCTV cameras and dash cams because they often use different techniques to achieve their low light performance. For example, the sensor featured in the links you cited state that: "The sensor features an embedded active imaging system which synchronises (sic) external illumination and internal electronic shuttering."

This is a version of a technique used by a number of manufacturers generally referred to as DSS or "digital slow shutter speed". Sony calls their version "Sense-UP". Essentially, it is a digital technique that uses multiple slow speed shutter captures in a single frame of video so as to boost low light performance between 2x and 128x. While this can be tremendously effective it can have serious drawbacks when it comes to capturing moving objects. So, where a traditional video camera would capture a moving vehicle with relatively good detail and minimal motion blur (like in a dash cam) a "Sense-UP" enabled camera will capture a moving vehicle at night as a streak or a line of bright dashes across the FOV. It is primarily effective in static situations such as the images you've posted of the front door of your home. This CCTV optimized technology would be useless in a dash cam.

"Sense-Up: "An image processing technology which allows user selectable digital slow shutter speeds in order to allow extra light into a camera thereby providing higher sensitivity in low light conditions. Also referred to as "sens-up"," sensup", "sense-up", "DSS", and "digital slow shutter".

 

[flip9]

Mono sensors (B&W) have higher quantum efficiencies than colour sensors due to the lack of a bayer filter. Basically means they can take in more light to produce a cleaner image.

I highly doubt you will find a dashcam with a mono sensor. Also setting a colour sensor to act like a B&W is pointless.

 

[Nigel]

Mono sensors (B&W) have higher quantum efficiencies than colour sensors due to the lack of a bayer filter. Basically means they can collect more light and produce a cleaner image.

I highly doubt you will find a dashcam with a mono sensor. Also setting a colour sensor to act like a B&W is pointless.

The pixels are basically the same so I would think they have the same quantum efficiency?

The difference is that in the monochrome sensor every pixel receives red, green and blue light while in the colour sensor each pixel only receives 1 of the three colours, so sees white light at only 1/3rd brightness.

However, since most of our street lights are still the orange sort that work at a single colour frequency, a monochrome dashcam at night would only have a small advantage over a colour one. Less than the difference caused by adding a CPL filter. Also, during daylight, having the white sky at 3x the brightness while the green grass is the same brightness is actually a disadvantage to getting a good exposure. B&W photography is great for creating high contrast images, but in a dashcam you want low contrast so that you can see everything.

Now there might be an advantage to a dashcam having a 4 colour sensor, the Bayer filter our dashcams use already has 4 sensors per pixel...

 

[flip9]

The pixels are basically the same so I would think they have the same quantum efficiency?

Pixels are separated by gaps and the way the bayer filter splits the light causes some of it to land on these gaps meaning they are lost. You also end up with different QE's for each channel in a RGB array.

The orange street lights you speak of aka sodium vapour lamps (589nm), at this wavelength a mono sensor would hands down beat an equivalent colour sensor. Heres the QE charts for the Sony IMX174:

Spoiler

Not saying they should make mono dashcams, thats just stupid. Mono sensors are fantastic for low light applications like astrophotography.

 

[SawMaster]

The Mobius camera has an option to shoot in B&W. I've done a bit of experimentation with it and it can be effective in improving apparent night time performance. What I learned from this however is just how important color can be in dash cam footage. For example, the color of a particular car is often one of the most important keys to positively identifying it, especially in a challenging lighting situation.

Oh great. Now I need a third cam in front (wide, narrow and now B&W) plus 3 more B&W cams for the sides and rear. Dashmellow, you are going to run me broke!

I think it is again clear that everything is a compromise in some way and that to get the best of one thing usually means giving up something else. It would be nice to have a top-level night-cam available but I doubt many would buy one so I can understand why they are not being made.

Phil

 

[Dashmellow]

Oh great. Now I need a third cam in front (wide, narrow and now B&W) plus 3 more B&W cams for the sides and rear. Dashmellow, you are going to run me broke!

I think it is again clear that everything is a compromise in some way and that to get the best of one thing usually means giving up something else. It would be nice to have a top-level night-cam available but I doubt many would buy one so I can understand why they are not being made.

Phil

You'll need one for the rear too!

Actually, keep in mind that I said "apparent" night time performance. The effect is not dramatic by any means. Basically, I set the color option to "mono" and boosted the EV by about 15%. Doing this can make some vehicles and objects stand out better at night in B&W when compared to color but it was not like you've suddenly got a new sensor or lens that performs in a vastly different way.

 

[Nigel]

The orange street lights you speak of aka sodium vapour lamps (589nm), at this wavelength a mono sensor would hands down beat an equivalent colour sensor. Heres the QE charts for the Sony IMX174:

Looks to me like a white car under the sodium vapour lamps with a monochrome sensor will appear twice as bright as it should be relative to a red, blue or green car or any green vegetation. Again, good if you want high contrast images, but not if you want to read those white number plates and also have a good exposure for everything else.

For astrophotography colour is not really an issue, you just take an exposure for each colour you want to see.

I think more use would be to have one of the 4 Bayer filters coloured in grey so that you can have HDR in a single exposure and have the bright white number plates really sharp, multiple exposure HDR causes blurring when there is a lot of motion between exposures.

 

[kamkar]

I Need some one to come up with a way to make my whole windscreen a see thru sensor, or maybe just sensor on the outside and huge ass 1:1 Tv screen on the inside
But then it would need to be at least 4K resolution as 1080p at that size and viewed that close must look a little like minecraft grafix