ir lamp

[ljarrald 0]

hi, i have put a standard cctv camera on the side of my house looking at the back gate, it has not got built in IR LEDs but can see IR light. i am thinking of placing a floodlight near the camera and point it at the gate. but i would like to put an IR filter in the light so it can't be seen by humans. would this work?

[mike_va 0]

If I look through a longpass filter at a light bulb you will still see a red glow. still fun to play with. also nice material if you ever need to put something behind some heavy tint.

 

Someone once told me you had to really go up in wavelength to not see it. Also probably will not be that efficient.

[rory 0]

Just buy a 930nm+ IR illuminator - that wavelength is invisible to the Human eye.

Not all cameras will see that light though.

[mike_va 0]

Just buy a 930nm+ IR illuminator - that wavelength is invisible to the Human eye.

Not all cameras will see that light though.

I was talking to Raytec the other day. They don't quote distance on their 940 so I was curious. It sounds like they were also saying you still end up seeing a glow, unless you go even higher in wavelength. They implied you could get roughly the same net effect turning down a 850 unit, in terms of usable vs. visible light.

 

I have not used 940 though so have no experience.

[rory 0]

I was talking to Raytec the other day. They don't quote distance on their 940 so I was curious. It sounds like they were also saying you still end up seeing a glow, unless you go even higher in wavelength. They implied you could get roughly the same net effect turning down a 850 unit, in terms of usable vs. visible light.

 

I have not used 940 though so have no experience.

it IS invisible

[ljarrald 0]

sorry, what i meant by 'so it can not be seen by humans' was baisically 'so it does not light everywhere up and annoy the neighbours'

 

if there is a red glow, that is fine.

 

this is the filter i have bought:

http://www.ebay.co.uk/itm/200659853964?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

[NotoriousBRK 0]

I was talking to Raytec the other day. They don't quote distance on their 940 so I was curious. It sounds like they were also saying you still end up seeing a glow, unless you go even higher in wavelength. They implied you could get roughly the same net effect turning down a 850 unit, in terms of usable vs. visible light.

 

I have not used 940 though so have no experience.

it IS invisible

 

I've yet to see a truly invisible IR illuminator.

 

Most SD camera sensors taper significantly above 1000nm in terms of IR light sensitivity, and all the 940-950nm illuminators I've seen STILL have a visible glow to them. You *do* have to get closer, but when it is pitch black out you still see some red light.

 

On top of that, the 940nm wavelength is (roughly) about 1/2 to 2/3's as powerful as 850nm light, so you need more power, meaning more cost.

[rory 0]

 

I've yet to see a truly invisible IR illuminator.

 

Most SD camera sensors taper significantly above 1000nm in terms of IR light sensitivity, and all the 940-950nm illuminators I've seen STILL have a visible glow to them. You *do* have to get closer, but when it is pitch black out you still see some red light.

 

On top of that, the 940nm wavelength is (roughly) about 1/2 to 2/3's as powerful as 850nm light, so you need more power, meaning more cost.

Ive used 700, 800, and 900 from Extreme CCTV, 900 was invisible to the human eye (unless Im blind).

Ive been right in front of them (off to the side ofcourse), no glow, no red light.

In fact I think one of the old UF500's I have in my garage now to test is 930nm.

99% of my work are pitch black apps, it actually kind of sucks.

 

I would generally suggest against it as with the high powered gear that is dangerous.

You dont know until your eyes start to hurt or your skin starts to burn (if within 3 feet of some).

 

There is the loss of distance though with the higher filter, approx 20-30%.

to compensate for some loss one can turn the power up higher.

 

I cant speak for other brands of IR though, only what I used.

[ljarrald 0]

i don't think my dad will like the idea of a 150w light being on all night (no, i don't want it motion activated although i accept i may have to) so what i am going to do if my dad kicks up a fuss is buy some stripboard, cut it to the size of the floodlight window and then solder as many ir leds on as will fit. then i will take the old lamp out of the housing, put the new board in, take the ir filter off the window and close it all up (not forgetting to change the supply from 240 to ~12v

 

what LEDs do you think would be best?

 

http://www.ebay.co.uk/itm/NEW-20-Infrared-LED-Emitting-Diode-IR-3mm-FreeShip-/330568062116?pt=LH_DefaultDomain_0&hash=item4cf76454a4#ht_1798wt_1041

 

http://www.ebay.co.uk/itm/Lot-50-PCS-5mm-IR-infrared-LED-850nm-Wavelength-Diode-/280750294626?pt=UK_CCTV&hash=item415e058662#ht_1557wt_907

 

http://www.ebay.co.uk/itm/50-pcs-5mm-IR-infrared-LED-940nm-Free-Resistors-/180674211058?pt=LH_DefaultDomain_0&hash=item2a1105acf2#ht_500wt_1056

 

- luke

[Numb-nuts 1]

I don't know what all the fuss is about. your typical IR flood isn't that visible anyway. Just ususally an insignificant red glow. Unlike cameras, you can mount them way high up and looking down on the area to be lit. Contrary to what most people think, they do not have to be looking along the same path as the camera, in fact they benefit often from looking at the area from a different direction so long as it isn't direct toward the camera. If I get the opportunity to work with IR floods, I try to position them across the area to be lit so that the camera doesn't suffer 'wash out' making identification useless. I have tired diffusers but haven't had that much success with those yet. The best I have managed is IR light flooding DOWN on the area. Unfortunately this isn't always possible.

 

I also like to use white light security lights operated by PIR so they aren't on all night and LED ones are now available with a much better value of light for cameras it's not so intense.

No need to record when nothing is happening, but if a PIR is activated, you can light the area and record what the camera sees. A Compromise? Yes it is!

[ljarrald 0]

an IR lamp on ebay is about £50 inc P+P, a halogen floodlight and diffuser would cost me no more than £10.

 

i want my cameras recording 24/7. although i have it setup so that when nothing is happening the frame rate is only about .5FPS but when motion is detected it bumps it up to 5.

 

i can't have a bright floodlight as it will shine into neighbours windows and disturb their sleep.

 

mounting the light higher than the cam is possible but would that not create shadows on the face?

[rory 0]

You get what you pay for.

Good IR costs 10x that.

[ljarrald 0]

that may be true but i don't really need a good one. as long as i can see faces i'm happy. i have modded cameras and various other things to get them to do what i want in the past and i don't mind doing the same with an IR lamp.

[rory 0]

Another option is to look for used or bad IR cameras, and just use the IR from them - can sometimes get them for free or next to nothing. Then the IR is in its own housing already.

[ljarrald 0]

yeah, i was thinking about that. ALL my cameras on my system are used from ebay. they are all 480TVL or above. most are 520 (or whatever the standard beginning with 5## is)

i think i will probably just go for the leds on proto board inside a floodlight housing unless i find a camera with ir in a skip, demolition site or ebay.

[rory 0]

Call local alarm or security companies, as if they have any bad IR cameras they are throwing out, thats how I got my cameras, all used, some bad and i just fixed them

[ljarrald 0]

Call local alarm or security companies, as if they have any bad IR cameras they are throwing out, thats how I got my cameras, all used, some bad and i just fixed them

 

i got a vantage camera for 99p from ebay as spairs or repairs. the iris was fecked. i spent a long time fiddling with it, it was almost done and then i dropped it and the pieces went everywhere so i just gave up and stuck a lens from a different camera in. the other camera now has a fixed iris, fixed focal length lens in, not the best but its fine for where it is.

 

ringing a cctv co is a good idea, i'll do that today!

i keep meaning to ring some demolition companies for stuff from buildings they are gonna pull down (alarms, cctv, emg lights, tannoys, etc) i have walked past a couple of building sites in the past, asked if i could go in and been given permission. one company said they were required to 'soft strip' first and if someone like me took stuff for them it would benifit them but due to my age i was not allowed on site so they said they would turn a blind eye if i went at night when the site was closed

[beckosecurity 0]

There is unseen IR LED camera at night now. You can have a try of this kind of cameras.

[MaxIcon 0]

You can get some pretty decent IR illuminators from Amazon for a reasonable price - search on YY Trade IR30 for one. Not expensive, has a photocell to turn it off in the day, runs from a standard analog cam PS, and mine really lights up the area. It claims it's weatherproof, but I haven't opened mine up yet to check.

 

Likewise, DealExtreme has IR rings for cams for $3-5 each, shipped, if you don't mind a little DIY. It's a bit riskier than buying from Amazon as far as performance goes, but check the ones with good user reviews. Shipping's slow (often several weeks), but I've ordered a lot of stuff from them with no problems.

[ljarrald 0]

i have decided to just use a floodlight with PIR and photocell as its easier. thanks for the help though