Free-track IR 2 DOF?

[albx]

Originally Posted by julian265

You can't see IR

i was talking about normal light, not IR... and probably IR direct to your eyes is more dangerous than the normal light

[swiss]

Originally Posted by Blackdog_kt

Yup, if you position LEDs near the camera i think there's nothing stopping you from using reflectors.

There are (standard)webcams with integrated IR LEDs on the market.

[Blackdog_kt]

Originally Posted by swiss

There are (standard)webcams with integrated IR LEDs on the market.

Didn't know that, you learn something new every day here

Originally Posted by albx

and probably IR direct to your eyes is more dangerous than the normal light

Actually i think it's not. IR, visible light, lasers, radio waves, it's all the same thing. What changes are the frequencies/wavelengths, which is also a measure of the energy each beam carries.

Higher frequencies means shorter wavelengths and higher energies. That's why in the 40s most radios were short-wave radios...the beam had enough energy to travel far, scatter across the top portions of the atmosphere and then come back down on another part of the continent, so that the resistance fighters in occupied europe could listen to BBC for coded messages

In all this, IR ranks below the visible light in the amount of energy it carries. In that sense, looking directly into your TrackIR LEDs is less harmful than looking at the sky and certainly harmless when compared to other higher frequency devices we carry on us or spend time around every day (like for example a 2.4Ghz wireless router).

Not playing smart**s here, i just wouldn't want people to be scared of using head tracking when it makes such a big difference

[swiss]

Originally Posted by Blackdog_kt

Didn't know that, you learn something new every day here

Night Vison webcam rings a bell?

[albx]

Originally Posted by Blackdog_kt

Didn't know that, you learn something new every day here




Actually i think it's not. IR, visible light, lasers, radio waves, it's all the same thing. What changes are the frequencies/wavelengths, which is also a measure of the energy each beam carries.

Higher frequencies means shorter wavelengths and higher energies. That's why in the 40s most radios were short-wave radios...the beam had enough energy to travel far, scatter across the top portions of the atmosphere and then come back down on another part of the continent, so that the resistance fighters in occupied europe could listen to BBC for coded messages

In all this, IR ranks below the visible light in the amount of energy it carries. In that sense, looking directly into your TrackIR LEDs is less harmful than looking at the sky and certainly harmless when compared to other higher frequency devices we carry on us or spend time around every day (like for example a 2.4Ghz wireless router).

Not playing smart**s here, i just wouldn't want people to be scared of using head tracking when it makes such a big difference

it's dangerous for long exposure because you can't see it, it's different with the visible light that the eye will protect itself closing... don't say things that you can't prove for sure.. and you know exactly the IRled's wavelenght you are using? Can you measure it or just read the specs the manufacturer say?

[Korn]

Of course the small quantity of IR radiation a few LEDs will produce has no adverse effects for you eyes or anything else. Just like visible light, it takes a lot to damage your eyes. That's why there can be so many products using IR LEDs (webcams, TrackIR, remote controls)... if they were hazardous to your health would they wouldn't be on the market in the first place.

The reason IR LED cap/clip/whatever are used more than IR reflectors is very simple: they're much more effective. Reflectors will only bounce back a small quantity of the IR light. LEDs provide better tracking and are less susceptible to parasite radiation sources (although an incandescent bulb right behind you will still mess up things big time).


PS: another happy Freetrack user here. You should know that for 2 axis movement (2DOF if you wish) you only need a single LED. But why settle for that when you can have 6DOF with 3 LEDs. In other games, of course .

[SEE]

Better off having a three point for a standard 2 DOF IL1946 set up. The difference is that that you get panning by slight rotation of the head as opposed to moving your head sidewards and upwards (which I found really irritating!) with a single point setup. I never tried to suss if this could be remedied in the FT software as I was just checking that everything functioned with a single standard LED then made the three point set up using IR Led's. I have two installs (clean 2 DOF and modded 6DOF) and use 3 point in both.

[julian265]

Originally Posted by albx

it's dangerous for long exposure because you can't see it, it's different with the visible light that the eye will protect itself closing... don't say things that you can't prove for sure.. and you know exactly the IRled's wavelenght you are using? Can you measure it or just read the specs the manufacturer say?

Being around strong sources of IR such as glowing hot metals can be damaging, sure - but I do trust the data sheets for the IR leds, and I also believe that they emit nowhere near the amount needed for damage to occur. Common video cameras have IR leds to give 'night vision', there are no health warnings on them, and they put out a $%&*( load more IR than the three low powered LEDs that I used!

[Blackdog_kt]

Originally Posted by albx

it's dangerous for long exposure because you can't see it, it's different with the visible light that the eye will protect itself closing... don't say things that you can't prove for sure.. and you know exactly the IRled's wavelenght you are using? Can you measure it or just read the specs the manufacturer say?

You could be right about the fact that the retina doesn't close to protect against non-visible light, i didn't think about that. On the other hand, all IR wavelengths are still below visible light energies. You don't need manufacturer specs to tell you that, IR is on the lower end of the spectrum according to elementary physics. If it's a higher energy, it's not IR anymore but something else

To be perfectly accurate we would need to calculate the intensity and volume of the radiation and not just the energy, but like others have said it's obvious that the kind of LEDs used in head-tracking devices are low powered compared to other applications.

[WTE_Galway]

Well just don't be clever and try and use industrial IR lasers for illumination.

I would probably also avoid pointing a military night vision IR spotlight directly into your face from 1m away as well

In those cases near light frequency IR radiation damage occurs through focusing the IR on the retina which heats up.

Apparently the IR LEDs used in domestic appliances like TV remotes simply do not have the power to do that.