IR Adapted DSLR with IR Constant Light Source.

adrianday

adrianday

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Adrian
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I'm about to commit to getting a Nikon D7000 converted with a 830nm filter. The primary use will be for cliched IR landscapes.

As a side, I'm interested in the possibility of photographing people in near dark or pitch black. And no, I'm not a pervert.

Was wondering if anyone had used an IR LED Light such as the ORDRO LN-3 and what their overall opinions were (esp. with a 830nm filter)? Whilst the specification implies that the LED's aren't visible, I've seen a video that suggests otherwise.

Thanks in advance,
 
Hi Adrian,

I don't have a definitive scientific answer but my previous employer manufactured visibility sensors using IREDs, operating at a wavelength of 850nm. We were often asked if the IR light could be seen by the human eye and would respond with a negative answer. My understanding is that the human eye has a response between about 350 - 700nm and that ties in with another of their products - an ambient light sensor which the ICAO and FAA require to be tuned to the response of the human eye. That sensor was fitted with a filter in the 420-675nm range, with a peak at 565nm.

Hope that helps :)
 
Not tried with LEDs but it is easy to adapt a flash. Putting a IR passing filter on the front of a normal Nikon SB600 works well, it is slightly visible to the human eye, but only as a faint glow, used this with a 720nm adapted D90.
 
adrianday said:
I'm about to commit to getting a Nikon D7000 converted with a 830nm filter. The primary use will be for cliched IR landscapes.

As a side, I'm interested in the possibility of photographing people in near dark or pitch black. And no, I'm not a pervert.

Was wondering if anyone had used an IR LED Light such as the ORDRO LN-3 and what their overall opinions were (esp. with a 830nm filter)? Whilst the specification implies that the LED's aren't visible, I've seen a video that suggests otherwise.

Thanks in advance,
Click to expand...

Yes this will work without issue, I work in industrial machine vision and we often use a camera with a band pass IR filter (camera is already sensitive to IR) and a similar wavelength light source. A few points:-

20m range from such a small unit is optimistic!
You may get a faint red glow form the LEDs, some of the cheaper IR LEDS do this.
Many phone cameras will happily see IR light sources - very useful to test if they are working!
You will 'obviously' get some very weird white skin effects!
 
First of all you need to understand that they do not capture infrared light strictly but near infrared (it is the wavelength between IR and Red). Also, I would recommend converting with a 720nm filter as this also capture some visible light which is much better if you try colour infrared (false colours). You can still produce the traditional B&W infrared so it is just more versatile.

Dave
 
Kaolin said:
Not tried with LEDs but it is easy to adapt a flash. Putting a IR passing filter on the front of a normal Nikon SB600 works well, it is slightly visible to the human eye, but only as a faint glow, used this with a 720nm adapted D90.
Click to expand...
I fitted an IR filter to the built-in flash of an Instax Wide 300 so it would fire a couple of manually set slave flashes. Worked as well as could be expected. I used a high wavelength filter and don't recall seeing the flash fire behind the filter during testing.

Have little interest in colour infrared thus my choice of 830nm. I was hesitant of using a speedlight given the likely illumination drop-off. But that said, cutting a cheap IR filter to size and fixing it to a big old Yongnuo with Sugru could be fun to try.

What sort of range did you get with the SB600 and what ISO?
 
Bristolian said:
Hi Adrian,

I don't have a definitive scientific answer but my previous employer manufactured visibility sensors using IREDs, operating at a wavelength of 850nm. We were often asked if the IR light could be seen by the human eye and would respond with a negative answer. My understanding is that the human eye has a response between about 350 - 700nm and that ties in with another of their products - an ambient light sensor which the ICAO and FAA require to be tuned to the response of the human eye. That sensor was fitted with a filter in the 420-675nm range, with a peak at 565nm.

Hope that helps :)
Click to expand...
As @Mr Perceptive said in his reply, it's likely that the cheap IR LEDs in the unit I'd linked aren't of the same high spec your previous employer used. I watched a review on YouTube and could see when the lights were switched on in a normally lit room - but I can't rule out that his may be due to the video camera being used to make the video.
 
Mr Perceptive said:
Yes this will work without issue, I work in industrial machine vision and we often use a camera with a band pass IR filter (camera is already sensitive to IR) and a similar wavelength light source. A few points:-

20m range from such a small unit is optimistic!
You may get a faint red glow form the LEDs, some of the cheaper IR LEDS do this.
Many phone cameras will happily see IR light sources - very useful to test if they are working!
You will 'obviously' get some very weird white skin effects!
Click to expand...
I'd be happy with 3 or 4m to be honest for what I have in mind. The possible visible glow from the LED's will be a show stopper for what I had i mind. The skin/eye effects are part of what interests me. (Whilst not a pervert, I'm certainly a bit weird.)

Today, I found a speedlight with interchangeable IR and UV heads. Link here. Ideal for what I suspect I'd need but for the price. Sunpak used to make an IR hammerhead flash yonks back. They're as rare and expensive as hens' teeth on eBoi.
 
Thanks for all of your replies. The thought of a filter over a speedlight is I think worth a try. Going to sleep on the thought of 720nm but have to say I'm not entirely convinced given that if I were to use a flash with a filter closer to 700nm in order to maximise the light, there's a chance it would be visible (if only momentarily). I'll compare some more 720nm vs 830nm examples tomorrow.

Thanks once again.
 
Another thing to bear un mind is the camera sensor senitivity. The further you go into the IR the less sensitive the sensor will be, so you will need to increase the light source power to retain the same exposure.

For the cost of that LED light source its worth trying to see if there is a glow, but you only have to look at cheap day/night CCTV cameras to know there could be a glow.

To be convert,s you could go further into the IR say at 940nm but you will need more light power to cope with decreased sensor sensitivity.

Since there is a lot of experimentation going on here you might want to consider getting the camer converted to Full Spectrum, and then just putting appropriate filters on the lens.
 
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