30fps v 60fps

I think my bottom line is to tweak the settings week on week and see what happens.
 
I've got saved footage going back to when I got the V3 so I can compare various conditions through various firmware.

It only came to light because there is a strange new, what we think is a speed camera, on the M4 but is nothing like anyone has seen before. Not Specs and not Hadecs. It's front facing and has flashed me twice even though I was under the limit.

I didn't notice it flashing when I was driving so I'm wondering if it one of those strange effects you get triggered by the dashcam LED that I have activated.

The freeze frame isn't as sharp as I'd expected so time to investigate:

vBAK6rf.jpg
It looks like what you encountered was a flashlight from a speed/red-light cam. Those cams are equipped with flashlights in order to capture vehicle’s license plates under low light condition. During “old” days, they used “regular” camera flashlights. Due to safety concerns of driver distraction, the current version of flashlight uses infrared which is invisible to human eyes. In general, digital cameras could “see” infrared unless an internal infrared filter is present.
 
As Dashmellow mentioned above, it is beneficial for dashcams to receive more light exposure under poor lighting. vvs49 mentioned a new A119 V3 lens which could give double amount of light to its sensor. This would double the shutter speed of A119 V3 and result in sharp image, especially, under low light conditions.
 
To the above posts:

On Sunday, as I passed that new camera setup I watched those lower 'things' very carefully and neither of them flashed. But, on the subsequent footage the lower one does appear to light up, so I'm now 99% confident it's the dashcam LED that I have set to on.

Regarding the motion blur, Viofo have been in touch directly after reading this thread and have given what they bel8eve to be the reason. I now have to test their theory over the next few weekends to confirm.

= watch this space.
 
Latest test complete. Lens angle back to what it used to be.

Lighting conditions less than perfect, dawn, but light enough for no headlights. Some motion blur still present.

iRNM8Lt.jpg


This one must have been under 1.03 as it was Feb 2020, lighting looks dull so maybe a fair comparison, a lot sharper at 50mph still :

tDNenwS.jpg


Next weekend, back to 1.03 and same journey / times
 
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I appreciate that but I'm just trying to get back to what it used to do. Almost every freeze frame I create from pre v 2.00 is sharper than now.

The info I've received, from those in the know and reading between the lines, is that when HDR was implemented the Menu Off / On actually means Low / High.

I'm happy to keep testing and next week's run with 1.03 will hopefully let me know whether 1.03 is better for my needs.
 
One thing I have noticed is that the lens angle does move slightly as in between the ratchet clicks there is some easy movement ...... sorted with a cut to size rubber washer :

It's now solid :

sY37d7b.jpg
 
I've just done a run using the latest VVS Mod 205 and it looks good.

The colours seem better and freeze frame is good, but, I was only tootling round town and didn't get above 41mph.

Also, the sound is still fine, a criticism beyond version 2.00

So I'll run this over the weekend when I will be getting up to 60mph on the M4 again.
 
I picked up an A119 V3 as my first ever dashcam last week, and right out of the box I set it to 2560x1440p, 60 FPS, high bit rate, and HDR off. After playing with it for a few days I found this thread and decided to try 30 FPS. One of my expectations was that the file size would be smaller, but instead the files became larger. For the first few days the three minute file sizes were pretty consistently around 595 MB, but after dropping to 30 FPS the file sizes averaged around 676 MB. I used a program called Mediainfo to examine the files and found that the 60 FPS video had a bit rate of 27.1 Mb/s and that the 30 FPS file was running at 30.3 Mb/s. If I did my math correctly it looks like the difference in bit rate over three minutes roughly accounts for the difference in file size. What this illustrates to me is that all things should be considered when configuring the cam because settings may not be as separate as you might think.

Previously I tried H265 encoding with 60 FPS and found that the file size dropped by around 50 MB. Nowhere near the 20% that some have stated. I tried H265 again tonight with 30 FPS and it reduced the file size by 126 MB which was kind of impressive until I looked at the video data. I found that the bit rate dropped from 27.1 Mb/s when using H264 to 24.6 Mb/s with H265. So the file size reduction isn't just due to a more efficient codec, it's also due to the bit rate being lowered.

For now I'm sticking with H264 and 30 FPS until I can prove to myself that some other setting is better for my situation. The file size is a bit bigger but storage is relatively cheap. My next decision to make is whether to use HDR.
 
So the file size reduction isn't just due to a more efficient codec, it's also due to the bit rate being lowered.
A more efficient codec requires less bitrate, and less bitrate requires less file size.

(Files at the lowest level are made up of bits.)

However less bitrate and smaller files does not necessarily mean a more efficient codec, it may just be a codec that throws away more information, giving a less detailed image, and when you want evidence, you may want detailed evidence, so smaller files are not necessarily a good thing! Always check the quality of what you end up with, don't just listen to numbers and assume that either less or more is good because that is what you saw written somewhere.
 
Hello @robpur - Well done and well shown (y) But I encourage you to not stop with the numbers- take time to appreciate the approach of @Kremmen and seek the best vids with the best details for your situation regardless of these interesting details, knowing that things are not always what they seem to be or what you might expect of them. Only in actually trying do we discover the real-world results ;)

Phil
 
Thanks for the feedback Nigel and SawMaster. It is good advice to make decisions based more on video quality than on the numbers, but at this point since I've only had the cam for a week I don't have a large enough video library to make meaningful comparisons. Although I drive the same route to and from my office every day, the weather where I live is highly variable which makes it hard to find two days with the same lighting conditions within a week. The best things that I've done so far to increase video quality is to put more effort into keeping my windshield clean and changing my wiper blades. :)
 
My testing is going to be delayed a few days as I'm not travelling to Reading this weekend. Probably Tue or Wed and that journey will be mostly in the dark.

However, she is making IKEA noises and that will involve a trip along the M4 from J11 to J12, in daylight, up to 60mph in the roadworks.

I'm still running high bitrate throughout as no one has posted that medium has any advantage over high.
 
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