HDW4631C-A or 4433 or 2MP Starlight - what to buy?

sumguy said:
So at night, using external IR lights will have no effect then.
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Right @wopi82 put pictures of the 4239 not sensing IR in his review. Also a note that Dahua told him they would be coming out with a similar model that had IR lights (and ICR).
 
tigerwillow1 said:
I remember reading somewhere that the IPC-HFW4239T-ASE full color camera does not have an IR cut filter, and the spec sheets that say so are on error.
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Yikes, I had it exactly backwards, and it always has the filter in place. That's why I didn't buy the full color camera, so I must have had it straight at the time, then my memory flipped it backwards. Sorry 'bout that!
 
Sumguy your asking a lot of my questions....keep it going....
 
@mat200 - I posted a reply in your thread.

I'd still like to know why any (or all) of these hi-rez cameras go to B/W at night with the IR filter switched out. One possible reason - in a night, low-light situation you may have mixed lighting (white led, incandescent, florescent, etc) and the camera can't get proper colors or white balance without the IR filter, so rather than deal with customer complaints about color the makers just go to B/W for low-light / IR filter situations.

One way to fool the camera and see what color-mode no filter looks like is to take a camera, disconnect IR motor drive when camera is in night mode and then switch the camera to color. The camera will think it slid the IR filter back in place but it won't be.

The 4239 apparently has a fixed IR filter. Has anyone checked to see if there is a drive/slider mechanism for the filter in that camera - but maybe it's not connected? Might be able to move it in/out with the right external signal.
 
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sumguy said:
I'd still like to know why any (or all) of these hi-rez cameras go to B/W at night with the IR filter switched out. One possible reason - in a night, low-light situation you may have mixed lighting (white led, incandescent, florescent, etc) and the camera can't get proper colors or white balance without the IR filter, so rather than deal with customer complaints about color the makers just go to B/W for low-light / IR filter situations.
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wopi82 said:
After IR filter removal the colors are incorrect and the whole image is tinted purple. Then the camera changes the image to BW (by software) to get rid of these false colors.
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sumguy said:
One way to fool the camera and see what color-mode no filter looks like is to take a camera, disconnect IR motor drive when camera is in night mode and then switch the camera to color.
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Looks like some Ubiquiti cameras run with the IR filter removed for a few minutes before the camera switches to B/W.

Check out the first picture in this post:
#12
 
"After IR filter removal the colors are incorrect and the whole image is tinted purple. Then the camera changes the image to BW (by software) to get rid of these false colors."

The color-tint issue being described is presumably happening with the camera being exposed to out-door daylight lighting. Is there any verification that the same off-color tint issue will happen during night-time exposure?

Reading the thread linked to #12 (aristobrat post) - what's missing in these pics is a simple color-sample (a red, green and blue balloons, or hats, or cards). Something big enough, close enough to the cameras (ie where a person of interest would be).
 
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I've spent some time looking for video's or articles showing examples of low-light / no-light night-time images from digital cameras with IR filter removed. I didn't know that pro photography used modified DSLR's with IR filter removed but with specialty IR external filters and image post-processing software - but that's another thread. What I found was a lot of "convert your camera to night-vision" stuff, but not a lot of example pictures. Here's something that I found interesting though:
Can a Sony a7S II Compete Against Military-Grade Night Vision?
Can a Sony a7S II Compete Against Military-Grade Night Vision?
 
sumguy said:
"After IR filter removal the colors are incorrect and the whole image is tinted purple. Then the camera changes the image to BW (by software) to get rid of these false colors."

The color-tint issue being described is presumably happening with the camera being exposed to out-door daylight lighting. Is there any verification that the same off-color tint issue will happen during night-time exposure?

Reading the thread linked to #12 (aristobrat post) - what's missing in these pics is a simple color-sample (a red, green and blue balloons, or hats, or cards). Something big enough, close enough to the cameras (ie where a person of interest would be).
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Perhaps Dahua engineers need your expertise ..
 
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