FreeTrack Forum

Hi
I want to build 3 point cap and i need to buy some IR-leds.
in my area i dont find any OSRAM SFH485P. which ir-led performance i need That same to SFH485P led performance?
which color/size/View Angle i need?
For examples this IR- led is ok for free track? http://www.dealextreme.com/details.dx/sku.2399

And to finish i have one more question.
Regular led(no IR) with high mcd its good for free track?
Look this-  http://www.dealextreme.com/details.dx/sku.1105
The led is 14000mcd!!! this very high.

Thanks and good day.

hello eladh7

which ir-led performance i need That same to SFH485P led performance?
which color/size/View Angle i need?

Almost every IR led can do the trick.

color : wavelength
If your webcam isn't IR modded, 880nm leds will work better (some stock webcams even can't track 920 or 940nm leds, they simply don't see them).
If you webcam is IR modded, every IR led will work

size :
stick to 5mm leds.
3 mm leds are too small (dots aren't big enough in the tracking window).

view angle :
the wider the better.
BUT :
if you can't find wide beam angle leds, just get narrow beam leds and sand them to increase beam angle.

For examples this IR- led is ok for free track? http://www.dealextreme.com/details.dx/sku.2399

I don't like these , because i couldn't find the led specs (or i've overseen it   ).

No specs = difficult to guess resistor value.

And to finish i have one more question.
Regular led(no IR) with high mcd its good for free track?
Look this-  http://www.dealextreme.com/details.dx/sku.1105

Freetrack doesn't need IR to work, it needs high contrast.

The problem is , to get high contrast with regular leds, you'll often have to deal with light reflexion your screen.

thats not the case with IR leds (well there's light reflexion too, but since its IR , we don't care   )

So if you have a bunch of regular leds on your table, just give it a try.
If you have to buy your leds, better go directly for IR leds, less hassle.

cya

Thanks tristan68, i really help me  
So i buy IR led.