Hello from Oxfordshire, UK

Privateer

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RoadHawk DC3 (x1), RoadHawk HD2 (x3)
Hi everybody,

My background
I bought my first dashcam (a RoadHawk HD) in January 2013 as soon as the RoadHawk HD was released in the UK. In October 2013 I was in a queue of traffic when a car ploughed into the rear of my stationary vehicle at an alleged speed of 70mph (i.e. the speed that the driver later told the police, although I suspect it was more). Fortunately, I was driving a Land Rover product so my wife and I walked away but not without injury to us both, the vehicle itself was also driveable (one broken rear light) but it did need to be sent to the garage for additional repairs. Although I didn't need to use the dashcam footage for proof of fault, it did show the need to have a dashcam. When I played back the footage I realised that it was still in the default settings i.e. 720p so I took time to optimise the settings. I now always drive with a dashcam recording.

Dashcams used
At the time of the above RTC, I had only one dashcam, which was front-facing so I decided to get a second dashcam, another RoadHawk HD, to cover the rear of the vehicle. I then bought a third RoadHawk HD for my wife's vehicle. When RoadHawk released the HD2, I started to buy them to replace the HDs that had failed. The advantage of the HD2 was that it had HDR so the image was optimised for lighting conditions.

I keep all footage
I'm guessing that most dashcam owners just keep their dashcams running and overwriting footage until they need to use the footage, although I suspect a lot of forum members here also keep all of their footage. For the last few years, I've kept all forward-facing footage and the occasional rear-facing footage to refer back to should I ever need to. It's also nice to use a bit of dashcam footage in the holiday videos.

Why I've signed up to this forum
So far, I've always had RoadHawk dashcams but I've become a little disillusioned with the brand as the dashcams have all failed and been returned for repairs at least once. Whilst I've been happy with the footage I think that nowadays other brands have more to offer in terms of footage and features and price! I was recommended this forum by Kremmen and he recommends that I look at the Viofo A119 V3.

Regards,
 

Nigel

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Gitup F1, A129, B1W, B2W
I was recommended this forum by Kremmen and he recommends that I look at the Viofo A119 V3.
Welcome :)

Since you run dual cameras, you might prefer the Viofo A129 Duo, or even the A129 Pro Duo for 4K resolution.
 
OP
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Privateer

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Oxfordshire
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RoadHawk DC3 (x1), RoadHawk HD2 (x3)
Hi Nigel,

Thanks for the welcome. :giggle:

That's a few of the questions I'm going to ask before I start to replace my current dashcams.

I do prefer to run dual cameras, up until now, I have always preferred to run identical cameras front and rear for a number of reasons:
1. I have built-in backup, i.e. if the front dashcam fails then I can just swap the rear to the front.
2. I use 64GB cards which give me about 9 hours recording (1080p, 30fps, max bitrate), the dual camera would presumably use up cards quicker.

I need to balance picture quality against storage. Whilst I know that current dashcams can record at 2.7k and even 4k, I would like to keep to around 100MB per minute. I can achieve that on RoadHawk HD2s and DC3s when set to 1080p, 30fps, max bitrate (which I think is around 18-20 Mbps). If current dashcams have better compression then that would be very useful for me and allow me to perhaps go to a higher resolution.

Regards,
 

kamkar1

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10 years, many dashcams
Welcome to the forum Privateer.
 

Nigel

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2. I use 64GB cards which give me about 9 hours recording (1080p, 30fps, max bitrate), the dual camera would presumably use up cards quicker.
Yes, a dual 1080 camera uses the card 2x faster, but these days you can fit a card 2x the size, 64GB is small and cheap these days.

If current dashcams have better compression then that would be very useful for me and allow me to perhaps go to a higher resolution.
Unfortunately not, some do have H265 but it doesn't help much.

However 2x the resolution does not require 2x the bitrate to look much improved, on the A129 Pro 4K (4x resolution of 1080), it can go up to 60mbps on the front channel, but 30mbps still looks pretty good and far better than 16mbps 1080.

2K (1440) does make a big difference to plate readability compared to 1080, and 4K allows reading plates at 2x the distance.

I need to balance picture quality against storage.
Very few people keep everything, but spinning hard drives have got much bigger and cheaper over the last few years so coping with 4K should be easier than coping with 1080 was in 2013!

There is also the possibility of re-encoding video for long term storage. 4K can be reduced to 8mbps and still look very decent, might get a bit blocky for high speed under trees but blockyness doesn't stop you seeing what happened or reading plates. Of course it has to be automated to be practical.
 
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Privateer

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Oxfordshire
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Dash Cam
RoadHawk DC3 (x1), RoadHawk HD2 (x3)
Welcome to the forum Privateer.
Thanks, kamkar1

However 2x the resolution does not require 2x the bitrate to look much improved, on the A129 Pro 4K (4x resolution of 1080), it can go up to 60mbps on the front channel, but 30mbps still looks pretty good and far better than 16mbps 1080.
Thank you, that's very useful to know. When I started with the RoadHawks I think that they defaulted to 720p, which was too grainy for me and that is when I realised that 1080p would be much better. I then had to experiment to learn the effect vs practicality and usefulness of adjusting FPS and bitrate for footage quality and file size. I also had to experiment with contrast, EV, saturation, etc but at least those were made easier with the introduction of HDR.

2K (1440) does make a big difference to plate readability compared to 1080, and 4K allows reading plates at 2x the distance.
If I could use 2K (1440) then I can see that it would definitely help with a better picture and number plate readability. I've tended to max the bitrate for RoadHawk unit but if I could get away with reducing the bitrate without visibly degrading the footage then that would be very useful for file size.

I've heard that some dashcams have automatically adjusted bitrate, is that true or even common?

Regards,
 
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