washed out white in the picture

[blowrabbit 0]

I've installed a sort of do it yourself covert cam in a acoustic ceiling panel for a retail install to look directly down in your typical retail setting with 2'x4' flouresant lite panels in the ceiling, ect. Well, after the install the picture became way too bright or white. I suspected afterwards it got too hot and later put a computer cooling fan next to it to cool it down. The picture will occasinally turn good or color balanced for a moment then revert back.

the cam is a one inch by one inch, Weldex digital color ultra minature camera 1/4" draws only 100 milia amps, 420 tvl, o.5 min illumination, powered off a regulated power supply. with a pinhole lense. I did white out the metal surrounding the lense so to conceil the tiny hole better. Must say it was a lot of work routering out the wood behind the ceiling panel for the cam and then drilling the ceiling tile for the pinhole lense.

the coax run is only 50' . any ideas?

[securitymonster 0]

cheap camera. Its probably getting warm and then you get the bad picture.

 

Does the picture get a bit fuzzy before it goes dark?

[blowrabbit 0]

i think you mean before it goes too bright? and either way i am not sure i' ll have to watch and see. and once its gotten too hot i assume its toasted ?

[cctv_down_under 0]

is it looking at any material that is reflective?

[blowrabbit 0]

yes, lots of white paper tacked onto the walls. would it help to angle it a little?

[cctv_down_under 0]

Pin hole lenses are usually wide angle, so they spread a lot of light onto the CCD chip, white is obviously the highest heat signature, it is unlikely that this is the reason becasue the eye of the pinhole is so small I was hoping more for a refelctive surface, like a metal polished bench and a down light..I would say it is likely that the camera is just not good quality, is it a CMOS or CCD chip?

[ak357 0]

Pin hole lenses are usually wide angle, so they spread a lot of light onto the CCD chip, white is obviously the highest heat signature, it is unlikely that this is the reason becasue the eye of the pinhole is so small I was hoping more for a refelctive surface, like a metal polished bench and a down light..I would say it is likely that the camera is just not good quality, is it a CMOS or CCD chip?

 

Pin hole lenses do not spread lots of light onto CCD chip

That why Pinhole cameras require much longer exposure times than conventional cameras because of the small aperture;

[cctv_down_under 0]

i understand that...a dn I thought someone would pull me up, what i am saying is that due to the small aperture and lens that they tend to overcompensate...knowing that they will not get as much light, i could have said that the pixels are rounded so that light falls more evenly on each pixel rather than square pixels so that less gaps of light are on the chip or even said that they use a magnifying type glass to accentuate it... btu I thought it just sounded better this way...In truth you are right and I am wrong my bad, but ai was not meaning like a aspherical lens, moreover that the ccd make up allows more light to be captured and therefore they are succeptable to overshoot

[ak357 0]

i understand that...a dn I thought someone would pull me up, what i am saying is that due to the small aperture and lens that they tend to overcompensate...knowing that they will not get as much light, i could have said that the pixels are rounded so that light falls more evenly on each pixel rather than square pixels so that less gaps of light are on the chip or even said that they use a magnifying type glass to accentuate it... btu I thought it just sounded better this way...In truth you are right and I am wrong my bad, but ai was not meaning like a aspherical lens, moreover that the ccd make up allows more light to be captured and therefore they are succeptable to overshoot

 

no problem

[blowrabbit 0]

the camera specs

image sensor = interline transfer color ccd 1/4" format

effective pixel = 512x492

sync system = internal sync

s/n ratio = 46+ DB

resolution = 420 tvl

auto white balance

 

its called a digital color ultra minature camera

[cctv_down_under 0]

Can u manually turn ATW off

[blowrabbit 0]

no there are not adjustments on a camera of this size. its only one inch by one inch by 1/3 inch thick.

[cctv_down_under 0]

Can you tell me which one of these it looks like

[blowrabbit 0]

the one with the pinhole lens and my bracket that holds it does not take that handy little 90 degree turn. the cam can come with either lens

[cctv_down_under 0]

The reason I ask is because if the lens is adjustable in any way then it may be out slightly and this could cause this blooming, but I severely doubt it... I bet it took you an age to get it in there but probably the best advice is to take it out and try it in a normal environment adn see if it still happens, if it is fine in a standard room then I would suggest that either the camera is crapola or the connecting cable (not the BNC) the little plug in at the back top of the square is not fully in or has a broken or bent pin or MOST LIKELY it is overheating.

[blowrabbit 0]

i did put a fan on it to cool it down as i first thought it was from overheating. But the fan didnt help and it wasnt hot after the fan. i replaced it with another simular cam as the way that i mounted it with a bracket allows easy removal and reinstall. I havent checked the wire plug connection yet as i must do this after normal bussiness hours.

 

thanks again for your help.

[kensplace 0]

I have had problems with overbright pictures in the past when a cable terminated incorrectly (due to forgetting to set the 75ohm switch on the loop through to the right setting)

[jisaac 0]

it is probably a defective iris. Its not able to keep a luminance level that is somewhere around 100 IRE's normally. If you put the same camera at the same locaiton under the same lighting does it have a good picture?

Its probably not the area being covered but the camera that is covering it. Maybe the ir cut filter is not completely filtering out the ir giving the sensor to much light.

 

I would replace the camera and see if you have the same or different results.

[blowrabbit 0]

i did and it does have the same white out.

[jisaac 0]

really? can you post some images???

[blowrabbit 0]

its been a while since i posted images, i dont remember how? they are in wavelet files from a ge dvmre.[/img]

[blowrabbit 0]

well after an exhaustive effort i figured out how to post pictures here again and here it is.

 

your looking down from a height of about 9 feet over a retail counter. and notice how the walls with paper on it white out.

[cctv_down_under 0]

Hard to tell from that image, but looks simply like a white surface refelcting a very bright light, try using a diffuser on the light sourse

[rory 0]

what he said ..

 

Plus maybe just point the lens over a little more off the wall ..

 

Check the DVR AGC setting also .. you can turn that down on the GEs ..

Actually you can do that through WaveReader also ..

[blowrabbit 0]

Thanks Rory, again you've saved my ... the cam looks a lot better from both moving the angle and adjusting the AGC.