A problem any ideas?

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M107

Billy-the-Kid
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The picture is a monitor for 4x domes fitted to the side of a 15tonne wagon.

http://i83.photobucket.com/albums/j293/gazjothomas/DSC00070.jpg

Any ideas why the cameras are showing over exposed images?

No amount of trimming the settings/lens's can resolve the overexposure issue.

I think the fact the cameras are on when the vehicle is in motion maybe causing the cameras to fail, the one that is working fine is the only one that is forward facing, the rest are mounted along the sides of the wagon.

 
How hard would it be to swap them around? If you swapped a good for a bad you might see if it's the camera or wiring that's at fault?

 
Interesting problem.

Vibration would be one of my main concerns, the cab would be better suspended mainly on air for driver comfort, the rear of the truck whilst being on air suspension would be a lot harder so as to carry the main weight.

However this theory goes out the window when you think of all the rear pointing reverse cameras fitted to comercial vehilcles today.

So I would doubt vibration is the problem.

I would have a look at the system installed and try to see if the cameras have an individual contrast control.

Other than that I am just as perplexed as you are.

 
Evening Patch how you doing mate.

I've done that by changing the connections at the dvr & made up a temp RG59 lead. So I know its the cameras that are at fault & not the dvr or cabling.

Just trying to work out why they've gone t**s up, as the customer is wanting them replaced, but if it is a fault being caused by the cameras being in operation on a moving vehicle it'll be pointless just doing a like for like swap unless they change their sop's & dont turn them on untill the wagon is stationary.

 
I thought the same about the cab having better suspension hence thats the only camera thats fine.

 
Anyway I'm now off up the wooden hill to bedfordshire...see you all tomorrow.

 
have yu checked there isnt 2 much voltage at the cameras which is casuing a voltage hike in the camera board and therefore making the camera over expose due to higher voltage, and also have you checked that BLC option on the cameras menus (if there are menus on the cameras) hasnt been inadvertantly switched on think its prob BLC that may be the problem (Back Light Compensation) The BLC smenu of a camera basically its job is when looking at a bright object in front of the camera it makes the back ground darker and objects lighter if there is alot of light coming into the lens, (ie doorways) but if its setup in a normal area (where BLC wouldnt normally be used) then it can over expose the image to a unusuable image) that may help find th problem area at least, it is late, and i am going to bed my self in a second anyways. nite all :D

 
Hi as mentioned if the camera on the front is ok have they got an auto iris fitted (lighten and darken)with the normal daylight/sunlight.check the cameras for thier Lux levels.If they are on a wagon I would suggest that they are set up again using a test monitor,a fixed lens would be no good in normal daytime used on something that moves about.

If they are Auto iris's there will be an addittional cable from the iris to the camera.Or on the pcb,look for variable pots.

Do the domes have variable pots for adjustment these need to be adjusted with a constant light level i.e. bright sunlight.

 
Are these fitted on an appliance?

If they are - our ones have them fitted down here, and I think it is terrible that they have to do it.

Their job is hard enough as it is - Poor Mites. :(

 
No they are fitted to the side of a big command vehicle, none of the appliances have cameras fitted.....yet.

Thanks for the input everybody, I'm back out to the wagon next week so will try all the advice then.

 
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