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[JamesV6CDX]

Due to a couple of near misses where people have almost driven into me, I have fitted what I feel is a pretty decent Dashcam setup to my Mondeo. In the front I have a Nextbase 312GW, which has a 140deg wide angle lens and full HD, with speed / GPS etc and full 1080HD.

In the rear window I have a Nextbase 412GW, the next model up, which has 1440hd. Both are hardwired, without wires really visible, and on removable mounts, with the footage accessible via my iphone app - so it's a pretty cool setup.

The quality is excellent, but I have one problem.

The other evening, I was on a quiet 60 road, doing, you guessed it, 60mph. No other traffic around. An 02 plate mini came absolutely hooning up behind me, and kept coming to the point he was almost in the boot. I tried everything to get rid of him, including slowing down and pulling into the left on a straight bit, but to cut a long story short he was being a moron and seemed to be playing a game whereby he would back right off, and then come up behind me at breakneck speed, narrowly avoiding a collision IMHO.

Eventually I stopped in a layby and got rid of him.

I decided to review the footage from my supposedly decent range rear 1440hd camera. When I did so, I was amazed to see that the car in question, even at it's closest point, appeared to be at, what the camera made to look, like a fairly safe distance.

I asked myself if maybe my perception was incorrect, but having done some internet research, a lot of people are having this problem, and it appears people are saying the wide angle lens makes objects appear much further away than they actually are.

To me, this is useless. I was only looking at the footage out of curiosity, but, if it were for example to have been shown in court, the lay person (which includes the magistrates) wouldn't see much wrong with it. I once also had a car nearly wipe me out when he overtook in an awful spot, but upon looking at the footage, the distance was distorted to the point it actually made his overtake look pretty safe!

Does anyone else have any suggestions on decent quality dashcams, but ones which don't distort the distance / don't have wide angle lenses? Despite being a leading camera, I think it's pretty useless if it can't do this correctly, and I'm tempted to upgrade.

Shame because aside from this I really like the setup and the interface!

Cheers

[Andy B]

  ..... but, if it were for example to have been shown in court, the lay person (which includes the magistrates) wouldn't see much wrong with it.  ...

but wouldn't the magistrate believe the copper ..... 

[Doctor Gollum]

There's a song about that phenomenon...

[Mister Rog]

This is the age old problem with camera lenses. Wide angle and get much of the width of the windscreen, or "normal" and probably need two to cover one screen. Many phones have quite wide lenses, lovely view with maybe a tree or something in the distance, take the snap and can't see the tree.

I don't have the answer. I'm sure there must be a solution for dashcams out there 

[Viral_Jim]

I don't know for certain, but I think the problem is the wide viewing angle of the lens, the wider you go, the more distorted the image becomes, maybe keep the wide angle at the front (for max visibility and go narrower at the rear, after all, you're mainly looking for tailgating/people rear ending you. A narrower field of vision focussed on the area directly behind your vehicle should work for this.

[Fraggles Rock]

There's also an element of perspective. The mirrors are ten feet from the back edge of the bumper, whereas the camera is at the tailgate window and can therefore see the road immediately behind the car.

As an experiment,  point the front camera to the back of the car and see how the image changes. QED and all that

[Andy B]

..... The mirrors are ten feet from the back edge of the bumper,  ...

how far? 

[Fraggles Rock]

..... The mirrors are ten feet from the back edge of the bumper,  ...

how far? 

Mundeo estate...

[Marks DTM Calib]

Its wide viewing angle, not an issue though as there are other distance references in the shot such as white lines and you can even, if needed, make a specific measured distance to an object whilst recording it and interpolate the results,

[Omega999]

You need a real perspective lens, a monitor and a camera that can be zoomed in or out, better still, buy an ex-police camera system. These are relatively inexpensive and give the user the ability to do that human thing of looking with your own eyes and zooming in or out until the view on the screen is pretty much what you are seeing.

To the viewer at a later date, certain reference points in the image will make it clear whether the camera is showing a realistic picture or a distorted view that is zoomed in too far and therefore making the following vehicle appear closer than it appears. If you wanted to be really technical you could have used the same principles with the images you have to show what the clown behind was actually doing and believe it or not... even magistrates can understand that drawing 

[TheBoy]

Well, I think the moral here is, if you were doing the speed limit, do not slow down or speed up - if he is going for overtake, he might not be able to ascertain what you are going to do.

(I know you were doing the limit) If you weren't, then at least try to do the limit.  I know the do-gooders will be up in arms, but travelling slowly on a road is pretty antisocial.

[VXL V6]

As previously mentioned, it's to do with the wide angle lense, if you are using something like Registratorviewer to view the footage you can click the zoom icon once to get a more true to life perspective

[Migv6 le Frog Fan]

The only downside Ive found with my Nextbase dashcam, is that the DAB radio in the 190 struggles to pick up a signal for any stations if the dashcam is running. 

[JamesV6CDX]

Well, I think the moral here is, if you were doing the speed limit, do not slow down or speed up - if he is going for overtake, he might not be able to ascertain what you are going to do.

(I know you were doing the limit) If you weren't, then at least try to do the limit.  I know the do-gooders will be up in arms, but travelling slowly on a road is pretty antisocial.

I slowed once, whilst indicating left, on a clear very straight and unobstructed road one one occasion to encourage him to pass me. perfectly acceptable and unambiguous. At all other times my speed was bang on the limit with my driving not unpredictable in the slightest.

Anyhow I was really just asking about camera lenses and using that as an example, not posting to discuss his driving. He's long been written off as a tool

[JamesV6CDX]

And I totally agree. Those going under the limit when conditions allow are a real pain!