Hello everyone.  This will be on our blog in a few days when the pretty table is ready, however I wanted future and current builders to know that Rosco Grey does work with DI setups and you don’t need a ton of LED’s to do it.  We are currently using 50 Osram 485p’s and the 360 Vision modded with negative can easily pick up our fingers, zero pressure.  We think the Rosco Black will also work, that will be our next test.

Our blog, fingerpuk.tumblr.com , will have piccies and photos soon.

Take care, A.

Looks great.
Just subscribed to your rrs feed

Is it correct to say you bought 300 leds but only needed 50 ?

Kind of yes!  With all the stories of Rosco being a pain, we ordered 300.  With only one PSU available I built a 50 array board, tried it, and bingo.  Funny that it didn’t work through tracing paper though?

Hey Larky,
I also used rosco on my previous DI setup but I would discourage others from doing so since it’s takes much more IR light than with a different diffuser.  Right now I’m using a gamfusion 10-80 diffusing paper that works great.  It delivers a nice image with no hotspot.  It’s much thinner than rosco, which allows more IR light to bounce back towards your camera to be picked up as blobs.  So… for FTIR rosco is great… but for DI, I don’t think it’s worth the extra effort for a small boost in image quality.  Also… it’s usually about $16 per yard which is a bit pricey if you mess up multiple pieces (speaking from experience!)

Hey Miketavious

Your DI setup work wiht incandescent lighting on the environment? I thought that the best solution to block the external IR was rosco grey.

I’m amazed you got such good results with rosco grey. We placed a 48 led array approximately 10cm behind the rosco, pointing straight at it, and tested to see whether any infrared light got through. There was none! *scratches head*

Kudos to you for getting it to work!

I think it’s down to the fact we glued it in backwards, or upside down depending upon how you look at it.  The matt side is what the viewer is supposed to see, but we glues it matt side to the beamer to reduce glare.  That’s the only thin I can think made it work.  It’s been running for over 72 hours with about 1000 users in that time, no restarts, still fast, lights turning on/off, sun going past the huge windows etc.  When the show is over we’ll test with it glues on the other way.

I see in the pics of your blog two lamps over the table pointing to the wall. Are there incandescent lamps? they don’t affect your setup when you turn on/off them?

Nah, the table doesn’t care.  They are normal 60 watt bulbs to get attention onto the posters which explain what the table is.  You could stand there turnng them on and off all day, it would make no difference.

First of all, congratulations for your succesful exhibition.

Larky - 28 June 2008 05:30 PM

I think it’s down to the fact we glued it in backwards, or upside down depending upon how you look at it.  The matt side is what the viewer is supposed to see, but we glues it matt side to the beamer to reduce glare.  That’s the only thin I can think made it work. It’s been running for over 72 hours with about 1000 users in that time, no restarts, still fast, lights turning on/off, sun going past the huge windows etc.  When the show is over we’ll test with it glues on the other way.

Rosco Grey arrived and I found that no matter if the matt side is upside or downside. Only matter to reduce glare.

I have a BW Fire-I camera with two negative films, 24 OP298 leds (890nm), a 4mm glass and a box of 30x30x30 cm for testing. I compared vellum paper with rosco gray on the bottom side (camera side), without ambient light and with an incandescent lamp pointing to ceiling. You can see my setup and results in the attached images.

I see that with vellum and rosco, the ambient light affect the blob detection. With vellum, I can see brighter fingers in both cases on the camera image, but with rosco, the fingers turn black when I turn on the light.

I have a few questions about your configuration to figure how do you get to work well on variable light conditions:

What camera do you used?
Do you used negative filters or another filter?
How do you setup your leds on your box? in the center, on a corner, angled?
It’s posible to see a picture of your internal configuration?

Thanks for your help

Camilosw,

I had similiar problem with Rosco, in fact I couldn’t even get blobs as good as you. I would be interested to see your filtergraph as I didn’t have as much control over the settings as you appear to. Any chance you coul post it here?

Hello.

Pictures were available on our blog, fingerpuk.tumblr.com.  We had 200 Osram 485’s in 4 arrays of 50.  They were in each corner pointed up at the glass.  Xbox 360 cam with two pieces of colour neg film as a filter.  We used AlecP’s improved Touchlib I think, but basically it just worked.  We’ve tested on a new table at home, same thing, works perfectly.  Maybe we have a different Rosco?  I know some dealers think Rosco Grey is not the same stuff as other dealers think…

@technodai: Filtergraph I used wiht Rosco Grey.

@Larky: I ordered the xbox 360 cam to compare them with the Fire-I. Thanks for your help.

Let me know how it compares.  We have a Firefly we don’t like, a 360 Vision we’ve broken, about to buy another but looking at the Fire-I.

I will post the comparison as soon as the camera arrive.

I considered to test a FireFly, due to their CMOS sensor like the xbox camera. I know that a CMOS sensor is more sensitive to IR than a CCD sensor. I see many benefits in that camera over the xbox. The firewire port is a better port than USB (less cpu consuming, less latency), we can buy the BW camera so we don’t need to convert from color, and with the 60 fps we can get a more fluidity applications. The only problem is their cost. Why do you don’t like the Firefly camera?

Xbox 360 camera arrived. Same setup as the previous comparison with the Fire-I. I used AMCap to change the camera parameters.

Larky, can do you show me the parameters you used in the camera?