Camera looking at the sun

[Scruit 0]

I have a DVR in my car that uses a cheap ebay color bullet camera... During the winter months the low sun in the mornings will make the whole camera image go black if the camera sees the sun directly.

 

When I point a regular sony camcorder into the sky the sun will appear as a white circle, but the rest of the image will still be fine.

 

What is it about the sony camcorder that allows it to not be blinded by the sun like the cheap camera? If I wanted to buy a small camera for my mobile DVR that would not be blinded by the sun then what specifications do I need to look for? Is it a certain type of CCD sensor? Some kind of tint on the lens?

[Rooney 0]

Some bullet cameras do not have auto-iris lenses or back light compensation blc. I would look for a camera that has both. Auto iris actually opens and closes the aperture according to the light level going in. BLC compensates the picture, ie. a bright spot in the center is dimmed and the surrounding area lightened to compenstate.

 

Hope that helps.

[rory 0]

That .. and also the cost of the Chips used .. that may even be a Cmos Chip instead of a CCD . .. but even if it is a Sony CCD, there are so many variations, from low cost to high .. and the quality and features get better as you pay more. Basically, budget cameras do not react well to bright light.

[Scruit 0]

I just added a camera that has a fixed lens and backlight compensation and the sun glare is still as bad. Worse, in fact, because the new lens is wider angle.

 

I have a cheap Swann Microcam wireless that I put in my remote control plane and when it sees points at the sun it shows up as a black dot and I can still see everything else. What do I need to look for in camera specs to get a camera that will do the black dot thing over the sun.

 

Attached is an example of what is happening with my current camera..

[cctv_down_under 0]

Firstly you need a camera lens that supports Auto Iris, a camera is not unlike the human eye, for you to look at the sun you would damage your eyes, therefore you squint to allow very little light in, the best you could do is buy a camera with multimple mode switching, this would allow you to set an area on the screen that is not affected by such bright light, what is happening is that the camera reads the brightness as a whole but bright white light is considered "HOT" and if there is too much it will try to electronically adjust the image or close the iris.

 

No camera should look dorectly at the sun, but some modern cameras allow you to use a wide dynamic range, IE very bright and very dark on the same scene, so what you need to do is set your wide dynamic area to cover the path of the sun and enable the wide dynamic only at certain times, so my suggestion is a Bosch XF using two modes and a timer relay, I would also use UV filter on your lens!

[Scruit 0]

The camera supports auto-iris in dc or video drive. I have ordered a 4mm dc drive auto-iris lens for the camera. We'll see how it goes.

 

As long as the camera is not being damaged then I'll probably just live with the bleaching (UV filter you say?) I only ever have problems in the winter time when driving east in the morning and west in the evening. I probaby only 'lose' about 30 seconds of video to sun glare from my morning commute of 30 mins - but knowing my luck that's the 30 secs where I'll need the camera.

 

I'd like to post links to example videos on youtube but the forum won't let me post links... ?

[SBTVideoman 0]

The other thing to check - is your bullet camera equipped with IR LED's?

Because if it is, it also means that the camera CCD is NOT fitted with an IR cut filter...if it was, it would not be able to see the IR LEDS reflecting off the objects they illuminate.

 

BUT...the sun is also pumping out lots of IR radiation. This could be saturating the camera electronics..

[Scruit 0]

I installed a 4mm DC Auto-Iris lens and here's the result I get when looking at the sun.

 

 

 

 

The sun in completely in shot, but the camera is still able to see enough of the road (driveway in this case) to be useful. This camera is intended to provide evidence in an accident, and lane position, direction etc is all visible. This also allows me to aim the camera further up so I can see the status of traffic lights until I'm almost under them - another potentially vital piece of evidence in a collision.

 

This is great. THe image will be a little clearer still after I wipe away the greasy fingerprints I left during the install. I also set up a CRT TV outside and hooked it into the camera so I could focus it better - I had previosuly focused it using the 7" LCD screen in the car but I couldn't get a crisp picture no matter what I did. The CRT worked much better.

 

 

One last thing... What can I do to the camera to ensure it's not damaged by the direct sun? Or is the auto-iris going to do that?

 

 

Thanks for all your advice!

[Scruit 0]

As you can see in the above pic, grass appears as yellow. I thought this may be because of the sun - but I noticed today that the camera sees greens as yellow/orange.

 

I'm going to sawp the lens tonight to see if it's the camera or the lens. If it's the camera then I'll print out a color bar test and hold it up in front of the camera.

 

 

 

Is it possible for exposure to the sun without an auto-iris lens could damage the camera in a way that would make green look yellow? Could it be a bad lens?

 

 

EDIT: After a bunch of searching I found this prior post:

 

I have a Vista Day/Night 1/2" CCD camera which appears very similar to Baxall cameras (do they make them I wonder ?). Is it usual that natural green subjects such as leaves, grass etc appear very light and washed out. ? Browns, blues, reds etc seem to be ok as do green-painted surfaces. The problem seems to be confined to subjects that contain chlorophyll.

Thanks

Steve

 

The responses suggested that too much IR light might be getting in and that an IR cut filter may help....

 

If I hold a color card up to the camera and everythign looks good then should I go with an IR cut (to allow visible light but reduce IR light) filter? A "Hot Mirror" filter?

[cctv42 0]

Well I have cameras that I call the 480 BLM.

 

BLM= bright light masking. you can read the writing on a light bulb when its on.

 

If interested shoot me a email

 

mirkwoodlol@yahoo.ca

 

It wont be the lens it will be how the camera deals and processes light. or it is not a auto iris lens.