Doubt over accuracy of Multanovas speed cameras-Pics Include

**qwsoftware** · 04-01-2006, 07:14 AM

Front page of the west australian newspaper today, did anyone read it? Glanced at it today in a newsagents. Was saying when 2 cars are in the photo or car changing lane (sure if there are 2 cars in the photo, they cant fine you)

Got this from their site:-

Serious questions have been raised about the accuracy of Multanovas after a world-renowned radar expert claimed the machines could be out by up to 15kmh if speeds are measured while drivers are changing lanes.

Matt

**g-zona** · 04-03-2006, 02:50 AM

Any link to the online article?

**nvr2fast** · 04-03-2006, 04:07 AM

Yes yes... any article anywhere?!?!

**qwsoftware** · 04-03-2006, 06:23 AM

The online edition for the newspaper doesnt give much detail (only what I pasted) and isn't there today as only daily news summary.(http://www.thewest.com.au/)

I will get the old paper from the office tomorrow and scan for you to read.

It was front page, very interesting. in 2 lane carrageways, moving in lane towards from Multanova when in the 22 degress angle can causes up to 15KPH increase in its reading!!!! The police admit it as well. Says world expert has proven it!!! - Anyone here?

Will get the artical tomorrow

Matt

**g-zona** · 04-03-2006, 06:41 AM

Originally Posted by qwsoftware

The online edition for the newspaper doesnt give much detail (only what I pasted) and isn't there today as only daily news summary.(http://www.thewest.com.au/)

I will get the old paper from the office tomorrow and scan for you to read.

Great!

Originally Posted by qwsoftware

It was front page, very interesting. in 2 lane carrageways, moving in lane towards from Multanova when in the 22 degress angle can causes up to 15KPH increase in its reading!!!! The police admit it as well. Says world expert has proven it!!! - Anyone here?

Cause of angle. When you change lines you have decreased the angle, so it's not 22 degrees anymore and you get false reading!
You can calculate this and is called cosine effect as far as I know.

**qwsoftware** · 04-04-2006, 03:58 AM

ok

here is the article, sorry but someone tore the page so miss last bit

Also an artical from yesterday about multanovas

Sounds rubbish the last bit of the article, saying police know when people change lane, how can in Western Australia they only take one photo!

Regards

Matt

**Dilip** · 04-07-2006, 12:35 AM

oh wow..... this is really interesting.

I do know, that here in HK, the police WILL NOT give you a ticket if there is another car next to you in the photo. Several cops have told me this, and i have personally been saved because 2 motorbikes were next to me while i got caught going 120 in a 70 zone and the police did not stop me at the roadblock up ahead after the camera flashed me.

However i've never heard about this changing lane theory. But mathematically it would make sense, that by changing lanes you are altering the angle of 22 degrees but i would think it can't alter your speed by that big of a margin? Maybe only a few KM/h here and there?

**qwsoftware** · 04-07-2006, 09:07 AM

Hello Dilip,

Yep I did not think the errror would be that much. In WA they take 1KPH away for error - far too low.

Would probably be easy for someone to calculate?
Anyone here could do this?

The multanova is set at 22 degrees, say in a 60KPH limit (38MPH) and you take 1.5 seconds to change lane from the outside lane to the inside lane, what will be the speed increase :?:

Matt

**Dilip** · 04-07-2006, 08:58 PM

Here in HK they give you 4Km off your actual speed limit detected by the multanova.

I got a chance to sit right next to the cops once and watch them set up a multanova speed trap. I find the way they adjust the 22 degree angle is very very very vague and not precise.