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where to get M12 lens with IR cut?

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A few years ago I bought a cheap "board" camera but apparently got lucky with a really good lens. The picture and color quality was quite acceptable.

 

So last week I ordered a few more board cameras (different sources to sample) and when they came in, same board but they've all got different lenses with IR filters on them (not IR cut).

 

I really want the daytime colors, at night the area is lit well enough to work at the minimum end of the camera's range without IR.

 

After asking a dozen ebay vendors, they all only have IR filter, only found one in Miami supposedly with IR cut and have a sample coming in to be certain.

 

What's interesting about these cameras from different sources - ALL their IR filtered lenses are DIFFERENT ! They are all 3.6mm but they have different levels of IR filtering, so there are slightly more colors (saturation) in one lens than another. One is horrible and everything is nearly pure black and white during the daytime (hence my other confused thread) but another one is slightly better, you can definitely spot reds and browns, another actually shows blues properly and the grass has a slight green to it, but the whole picture has a hue to it like you are looking through sunglasses (it definitely still has IR because at night the grass is white).

 

Can I somehow make my own filters on the cheap to experiment (something like exposed film, I dunno?) or is this implausible?

 

I think I am also going to try to buy 2.8mm to see even more - but I am sure I will have the same IR problem.

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Wow those are some really nice board cameras.

 

I bet they cost several times more than what mine did though.

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So is there such a thing as a clear gel IR-blocking filter?

 

That you get in sheets and cut down?

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You can always surgically remove the IR filter if you want, although it will make for an off color day shot, especially if its a cheap camera. Removing the IR filter from board cameras can sometimes be tough too as I have found that they are sometimes glued on.

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I've given up and am just ordering different lenses from different suppliers to see what I end up with.

 

Fortunately they are cheap enough to experiment.

 

I looked carefully at the one I got a few years ago and the quality is really nice - when I look at the new ones I got this week, it's typical made-in-china style where they slowly start to cut corners on the quality to increase profit. Metal housing is now plastic, glass is plastic, etc. One looks like it once had a filter coating and someone must have scratched it off to make it full spectrum, which is crazy.

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KLV-2812DN is the model you want, but again, not sure they come in an M12 thread.

Most domes and bullets that use TND Varifocal lenses are M13.

If its a fixed lens it wont have an IR Cut filter, that is placed over the camera chip.

In the AI Varifocal lens the IR Cut filter is part of the Auto iris mechanism.

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I believe IR-cut can also be a coating.

 

The bottom of the one lens I have that is actually IR-cut has a red coating.

 

Though it may very well be a carefully mounted piece of glass on the bottom or even a plastic disc, I dunno.

 

I'm up to a half dozen different lenses I've bought and none of them have IR-cut. I guess they just don't do it anymore.

 

I found this collection which carefully lists if they have IR-cut or not, but their prices are twice ebay plus shipping, so it will be a last resort:

 

http://www.electronics123.com/s.nl?sc=16&category=&search=lens%20filter

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I wouldnt waste the time. I tried to remove one of the plastic IR Cut filters from the Auto Iris mechanism before and ruined it, basically fingerprints damage it. You can buy the small IR Cut glass which is used for most fixed lens cameras such as ones that come with the M12 thread, and just glue that over the CCD yourself. I found it before in different sizes when searching online. If your camera has a varifocal lens its most likely an M13 though, which I believe those KT&C varifocal lenses are. Ive only seen one camera i gutted that had the IR cut filter in the bottom of the lens holder and that was a cheap CNB bullet, most had it over the CCD itself, or in the case of the AI lens, built into the AI mechanism.

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No it's definitely M12 (and not varifocal)

 

I would definitely not try to remove the filter (especially since I only have one lens with one and it's great quality).

 

How thin are those glass filters though, because the lens already has to get quite close to focus - I guess I can buy an extender.

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Its cheaper just to buy a new camera with an IR Cut filter built in.

Most color only cameras have a fixed IR Cut filter to block IR.

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I am trying to find something reasonable price-wise with mechanical switch filter.

 

Need to check opinions on the Digimerge DCD110043B

 

it's a $50 true day/night apparently:

 

http://www.digimerge.com/images/file/Specification%20Sheet%20for%20the%20DCD110043B.pdf

 

but maybe I should start a new thread for that

 

 

 

if they cant show real pictures on the spec sheet then all they are doing is selling crap. the picture they have on the spec sheet going day and night are the same picture colour turned black white. (same frame)

 

how many cameras are you looking at doing. is it worth all the time money and effort.

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I am trying to find something reasonable price-wise with mechanical switch filter.

 

Need to check opinions on the Digimerge DCD110043B

 

it's a $50 true day/night apparently:

 

http://www.digimerge.com/images/file/Specification%20Sheet%20for%20the%20DCD110043B.pdf

 

but maybe I should start a new thread for that

 

3.6mm lens, and TDN? I'll believe it when I see it.

There is ALOT of false advertising out there BTW,

I bought 3 cameras from Vitek not that long ago, they claimed it was a TDN with IR Cut etc, was nothing of the kind.

 

BTW, TDN is going to be much more than $50 in the US even at dealer cost.

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Yeah but problem is bullet and dome cameras generally dont use that type of device, in general TDN is only in AI Lens cameras and its built in with the AI Mechanism. Additionally there's alot more to a Day night camera than just blocking the IR or Removing it, thats evident with all the bad TDN cameras on the market these days. None of them can match a dual CCD though (2 separate cameras)

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TDN is probably under a price revolution this year.

 

The mechanical switch to move the IR-cut filter is down to $10 now

 

http://www.dhgate.com/ir-cut-filter/r-ff8080812b51ebc8012b52d4943a0f0c.html#1

 

It's usually cheaper than that but that is only for box cameras.

I have this one sitting here

20110524110529-1.jpg

 

Uploaded with ImageShack.us

This for bullets and domes. You can see how the AI and ICR are integrated on the lens itself. This is usually more expensive.

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Oh wow nice. Where can I buy those?

 

I just bought a couple of box cameras just to get TDN ability, oh well.

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