joat - 13 May 2007 09:50 PM

My understanding is that you have to buy a full kit first, and then subsequent cameras are cheaper ("NOTE: One full KIT must be purchased prior to ordering individual cameras, unless otherwise noted.").  *edit*, removed bit about charging a ton for stuff most people don’t need, as the kit seems to only be $100 or so.  However, for the FireFly MV, you have to buy one plus the kit, and after the first one, you have to buy them in packs of 5!  C’mon, it’s not like they’re Sam’s Club or BJ’s…

There’s got to be some other camera that exposes these controls; the hardware on a pointgrey camera isn’t really anything special, it’s nearly identical to Sony firewire cameras, and you can use Sony drivers to capture video without the SDK.

I’ve got another high-speed camera I’d like to try out, but it has no drivers and my USB fu is weak.  I’ve tried the simple things like finding a driver for the same chipset and changing the VID/PID to match with no luck.  If I get around to it, I might try setting up a spare box with linux and playing around with the drivers there, which gives a lot more flexiblity (or at least I might get *something* besides a code 10, device cannot start).

I thought you had to buy a kit too, but $300 was what WhiteNoiz said they were. I might start a group buy for people interested in the FireFly MV.

Sorry Gravano, I will start a Point Grey thread in the cam forum if need be…

you dont have to say sorry honey, keeping things in the right place is easier for people to trace if they are interested in a certain subject, anyway of course there’s a need for a point grey thread

True, true. Thread started.

Anyone found a source or know how to have made an IR LED strip?  Some companies sell “ribbons” of SMT leds on a 1/4” wide flexible or rigid PCB strip… I just haven’t found any that do this for IR SMT LEDs.

I have a 2 x 2 foot piece of 8mm acrylic would 40 LEDs(SFH485) be too much? 2 lines of 10 on top and 2 lines of 10 on the bottom. Is that overkill?

Blue - 26 August 2007 06:11 PM

I have a 2 x 2 foot piece of 8mm acrylic would 40 LEDs(SFH485) be too much? 2 lines of 10 on top and 2 lines of 10 on the bottom. Is that overkill?

two lots of 10 would probably be ok (20 total).  I have a similar sized piece and I am using 10 down just one side and it works, but it can get a bit weak on the far side if there is a bit of IR pollution.

I’m wondering why there are leds only on two sides ,
could it work better on the four sides ?
anyone already tried ?

Yes, some people use all four sides while others use only two. Sometimes two is enough which is why they only use two. It just depends on the size of the acrylic, and the intensity of the LEDs.

First of all I want to say hello to all the people around here.
I’m trying to build a 800mm x 600mm multi-touch with a visible “screen” of 770mm x 560mm.
I found some IR-LEDs with a viewing angle of 25° and a wavelength of 940nm.
The manufacturer recommends a forward current of 20mA.
My Acryl is 8mm thick.

I plan to light 2 sides (top and bottom) with 16 LEDs each.
1.) Is this IR-LED a good choice (why or why not?)
2.) Are 32 IR-LEDs enough for a bright daylight room?
3.) What difference does it make when I use a smaller wavelength (about 880nm) ?

Thanks for reading

@alkatrazi....firstly you are missing on a critical rating info… the Radiant Intensity of the LED’s you pan to use. i have serious doubts at the led’s you mentioned if their peak forward current is 20mA. you shud select a led based on their radiant intensity rating which is usually mentioned in their data sheets. anything above 100 mW/sr is a good option. so cant really say if these led’s are a good option or not.

again 32 led’s or more cant’ be determined unless you have the correct and required specs for the led’s ... i am using 130mW/sr led’s and have placed 1 every inch along the two logn sides (32") ... comes to around 32-33 to a side. they work pretty well in bright rooms.... a caution you’ll have to take is that your box shud be completely cloesed to avoid and ir flooding due to sunlight or tubelights. secondly very bright sunlit rooms will cause problems cause sunlight has shit loads of ir.

wave length is mainly for the visibility part.... most of the cam sensors are a little more sensitive to lower wavelength.... it simply goes like this… human eyes can see upto 700-750nm...whereas cameras can see a little more.... upto 950nm or so… so its better to go for ir’s in the <900nm range cause they’ll have better visibility for most cams....

hope this helps…

Sorry for the slow reply, but I had some things to manage…
Thanks for your opinion.
I now use TSHF5410. The datasheet can be obtained here:
http://pdf1.alldatasheet.com/datasheet-pdf/view/170309/VISAY/TSHF5410.html

I will posts any results hopefully soon.

so long

Alkatrazi - 11 December 2007 08:28 AM

Sorry for the slow reply, but I had some things to manage…
Thanks for your opinion.
I now use TSHF5410. The datasheet can be obtained here:
http://pdf1.alldatasheet.com/datasheet-pdf/view/170309/VISAY/TSHF5410.html

I will posts any results hopefully soon.

so long

Well they do have a Radiant Intensity of 170 mW/sr at Ie max, so I guess that’ll do. Idk what the 65 mW/sr under Typ. is for though..

@ kneli… they just bout typical values (safe conditions) and max values… (critical) so at typ votage of 1.4V it will deliver 65mW/sr and at 1.6V it will deliver 170mW/sr… one just needs to be carefull that the voltage is not more than 1.6V per led cause even slightly more voltage might toast the led. and secondly it also reduces the life of led.. not drastically tho.. so its safe to push em to the max values.. but they do look quiet kics ass …

alkatrazi how much are they costing you and how many are u plannin to use ( and what is ur screen size)

First, my screen is going to be 800x600mm (minus 10mm on each side for the aluminium frame).
My plan was to use 50 of the IR-LEDs, 25 on each long side.
They cost 0,42 € when you buy a minimum of 25.
Pics are coming online this week, I’ll keep you postet.
Now I have to polish my acryl ...

cu l8