Does this level of picture quality seem right? (front + rear cam)

[SGM26]

I understand that both cameras are recording at 1080p 30fps so picture quality is going to be lower than the 1440p I'm used to using, however many of the videos appear blurry or pixelated, particularly in low light. Number plates are typically easy to see in bright conditions but appear blurred somewhat in overcast conditions and more or less indistinguishable in the dark.

I've uploaded a few videos, both from the front and rear camera in bright, overcast and night time light conditions. I'm aware that YouTube's compression makes them look slightly worse hence I have included thumbnails of the video as viewed in VLC.
You can also download the original files (and some more screenshots) here - https://drive.google.com/drive/folders/1DES5CedF9on2RI06rpjkC7tHnqyz6p0N?usp=sharing

If anyone who also has the front and rear camera can let me know if this level of detail is normal or not that would be great.

Bright day - front

Bright day - rear

Overcast - front

Overcast - rear

Night - front

Night - rear

 

[SGM26]

Some more from this morning

 

[nb_matt]

Im not convinced by the quality of my pictures either. What firmware version are you on?

 

[SGM26]

The latest (22.5).

I've recorded a couple of clips this afternoon doing a short loop around some busy roads, one with the rear cam plugged in and another without (but set to 1080p30 for a fair comparison).

Not at home at the moment but I'll let you know if I notice any differences.

 

[SGM26]

Back home now and I've had a chance to look over the footage and there's definitely a drop in picture quality with the rear camera plugged in. All settings were the same (1080p 30fps, exposure 0, etc).

I've taken several screenshots (as closely matched as I could) with certain areas highlighted that show the differences in quality. The front + rear camera is on the left (red), the front only is on the right (blue).

Photos - Imgur

Videos:
Front + rear

Front only

I've sent an email to Nextbase support. I'd advise you also do a similar test to see if there is a difference in your recordings.

 

[Mtz]

1. You should move the lens a little lower to obtain at least 50% sky/50% ground. Never more sky. 45% of sky is enough.
2. The weather is not helping the image.
3. Is very possible when both cameras are connected the bitrate to be (much) lower compared to the bitrate when just one camera is connected. This is normal.

enjoy,
Mtz

 

[SGM26]

I understand you want more of the road than sky, It's normaly set much lower but I think I may have knocked it while removing the SD card earlier in the day and also while adjusting settings in between videos.

Again, I know the weather isn't helping, more light gives you a better image, but it doesn't get much better than this where I am at this time of year

I figured that would be the case, hence only allowing recording at 1080p30, but surely there is enough headroom to allow for the front to record at the same bitrate as it does without the rear cam. I've seen on other threads that people were having similar issues and after receiving replacement cameras (not sure if it was the front or rear they had replaced) the issue was resolved.

At the end of the day the footage is still useable, it just seemed like something wasn't quite right when I noticed some number plates were almost illegible.

 

[M8TJT]

The front cam goes from 2140? to 1080 HD when the rear cam is connected by design. Many peeps have been pee'd off about that.

 

[SGM26]

The front cam goes from 2140? to 1080 HD when the rear cam is connected by design. Many peeps have been pee'd off about that.

I know, but comparing apples to apples (1080p30 with the rear vs 1080p30 without the rear) there is a slight but noticeable difference.

 

[Kremmen]

I've been reading around and there are a few articles that explain that footage quality is not only dependent on the hardware but also on the transferred bitrate, as already mentioned.

Identical lens dashcams, one transferring data at 20Mbps is going to include more data detail than one only transferring at 10Mbps. Once you have 2 dashcams chucking data at one card quality will suffer according to the experts.

https://www.lifewire.com/beginners-guide-to-camcorder-bit-rates-487996

 

[SGM26]

Fair enough, I get that it's still 1080p only with less data, just wasn't expecting it to be as noticeable.

I'm not clued up on such things (as you can probably tell) but I wonder if it would be possible to set a bias to the front camera so it has a higher bitrate than the rear (if that's even possible). For me anyway most of the 'action' is happening in front of the car, not behind it (which isn't to say the rear cam isn't a valuable addition).

I wonder if the 612GW (assuming it had a rear camera port) would cope better with two higher bitrate 1080p video feeds than the 512GW since it's already capable of recording at 4K.

 

[Techifan]

Fair enough, I get that it's still 1080p only with less data, just wasn't expecting it to be as noticeable.

I'm not clued up on such things (as you can probably tell) but I wonder if it would be possible to set a bias to the front camera so it has a higher bitrate than the rear (if that's even possible). For me anyway most of the 'action' is happening in front of the car, not behind it (which isn't to say the rear cam isn't a valuable addition).

I wonder if the 612GW (assuming it had a rear camera port) would cope better with two higher bitrate 1080p video feeds than the 512GW since it's already capable of recording at 4K.

The 612GW appears not to have a rear camera port.

 

[Decking]

I have to wonder why the 612GW has no rear camera port, surely in trying to improve the brand it would have been a no brainer.
I’m currently running the 512GW with rear camera and an very pleased but at present have no way to upgrade.

 

[Auld Reekie]

Vid quality not so good there, as for the front cam are you sure the circular polarizer is in the correct position, the shadows look exceptionally dark. Vid clip where it looks like your pulling away from your house the cars opposite the reg plates seem unreadable. Another thing I find that increasing the exposure value by one step will lighten up these daytime clips.
As Kremen said it could be a issue with your memory card, I had similar problems when I first got mine so I splashed out on a Transcend High Endurance memory card, the difference was like night and day. Try viewing the clips in VLC Player, Replay can give poor playback quality, VLC is miles better.

 

[SGM26]

The filter is adjusted so that reflections on the windscreen are minimised (though I did note it did darken the image in certain areas - presumably due to the mixed nature of light incoming to the lense). I have considered trying it without the filter for a week to see how that changes things. I might also try increasing the exposure, I'm just a bit wary of overexposing things.

I doubt it's the memory card as I had recently replaced my old card (after having recording issues with it) with one recommended by Kremmen (Samsung EVO 128GB class 10 U3). Really pleased with it and the read and write speeds are considerably faster than the old card.

Yeah I've noticed Replay 3 doesn't do a spectacular job at playback but all of the screenshots are from videos as played in VLC.

I've had a response back from customer support regarding the issue and as mentioned above the drop in quality is to be expected as the bitrate is lowered due to 2 cameras recording to the same SD card (I assume this must be a limitation of the camera hardware\software and not the SD card).

 

[Kremmen]

I've tried various viewing software on my Win7 rig and surprisingly the one that seems to be the smoothest and less grainy is the latest Firefox Quantum browser ! I think it's up to version 62x now.

VLC seems to often produce some pixelation of the road surface just in front of the bonnet whereas Firefox doesn't seem so bad.

 

[Jacko956]

I think Nextbase has made a mistake offering this as a dual channel setup. I think the hardware is simple not up to it. And I think the £50 rear camera is producing higher quality than the £150 front. Something not quite right there. But on it's own, the 512 is great.