This blob thingy...Its very strange. I have a DSI-setup in the building/testing/getting-extremley-frustrated-stage. Kind of like yours, altough not as clean and well built. Since i got to little children that i want to use the table i havent been that strict in the looking-good-part of my table.
I got, right now anyway, the following setup;

This is about 32 “ in diagonal - made for a 32 “ lcd at first.
Plane glas - 6 mm (no scratch = good kidstable) and i dont think the risk of braking the glas is a problem because its resting on the endlighten…
Cover plastics ( dunno the english word for this but i use it for testing projectorimage and stuff. its a semitransparent plastic sheet with about 0.1mm thickness.
endlighten 8mm with around 95 osrams surounding it

Ps3 with ir-filter for 880nm - sort of bad focus altough i think its the best i can get at the moment.

As i wrote before i started my table for lcd but have now gone over to projector, atleast for the time beeing. This is cuz i did not get good blobs thru the lcd matrix, well actually i did a couple of times but not in the long run, wich is kinda strange. I have been testing this table for a couple of month now and just when i seem to get somewhere it just stops working. I have had good blobs with the coverplastics and projector fired upp, Just touching the glas gently. but then out of the blue i dont get none. And if i turn values higher you can see some blobs blinking. Kindof like the camera running wrong hertz or something. I dont really now. The main thing is i have had gooood blobs and calibrated and run some programs, got a bad framerate (15), tried to change it and then it stoped working.

Damn i feel like im 6 years old and trying to write english for the first time. ( Yes we (try) to learn english from 6 years in sweden. No good explanation, i know. I will try to get some videos of this dilema i got. And others with me.

Oh, when i got my setup working i noticed that its pretty sensitive to sunlight. Would sunscreen, you know the type you got on your carwindows, work as prjection image AND blocker?

Hmm..i got a project-thread in here somewhere....guess i outha dig that out here…
Gotta work some for now....
Cheers!

cdog

what’s wrong with your blobs?  can you try to move your camera toward the edge of the screen (from the bottom) and try to see, if it can see blobs at the edges? maybe there is a problem with the camera viewing angle?
and one more idea: which side of your 7D006 is on the bottom? the more mate one, or a bit glossier one? the idea is that, if your blobs’ light travels first more matte (mate, matt) side, then glossier side it can be more bright, than opposite way, when blobs light is diffused once more on matte side

Limpa - 15 May 2009 12:41 AM

[...]
Oh, when i got my setup working i noticed that its pretty sensitive to sunlight. Would sunscreen, you know the type you got on your carwindows, work as prjection image AND blocker?
[...]

Hey Limpa,

sorry to hear about the problems you have with your table. I know how this blurs the fun of building a table by yourself :-(
Let’s hope, you’ll find a solution with the help of NUI Group!

I don’t think, that these sunscreens would work, because if I’m right, the IR-rays have to go through the projection-layer until they reach your finger, but they can’t do that, if they were blocked by that layer.
I’ve also experienced, that DSI is very sensible to sunlight. I have to dim my room, if I want to get blobs. That’s unfortunately one of the disadvantages of DSI you have to deal with.

@zviangi: Conveniently I copy the answer to your queston out of my blog-comment

“Hey,

thanks! I don’t know, which side is the more matted one. Because I want to use fiducials some day, I put the better “readable” site to the bottom. So if I lay a magazine on the table for example, I can read the writing better as if I switch the sides.

This post explains it better.”

Concerning the first question...I haven’t really tried that, but I will do in the next days!

Hey guys,

Any improvements on your DSI setups with problems?
I had a 48” vertical rearDI that I converted to DSI because I couldn’t get the light even, and now I have the same problems as you. The surface is about the same: 111 x 72 cm EnL XL 8mm, but I use the 850nm led ribbon from environmental lights all around the edges and a 5mm glass surface for touch. Between the EnL and glass I use 3 layers of LEE 225 filter.
I also have this weird effect that blobs are more detectable in the center than along the edges. I have an 850nm omegabob BP filter on PS3 custom lens with 110° FOV.
Would be nice to hear from you if you could have some improvements.

Thanks
Greg

Hey Gregi,

unfortunately I coulnd’t make any improvements yet :(
But I will upgrade to four cams as soon as the multi-cam driver for ps3 eye will get released and I hope, this will deliver better results.

In the meanwhile I finished my diploma thesis and made a short movie of my table in action.
As already mentioned in the movie description: the table isn’t working very precise yet, so please consider that before hating on my baby!

P.S. Thanks to the great creators of all these wonderful applications, which made it possible, to demonstrate my table!

Hey cdog,
Your setups works quite nice!

I don’t know if you’ve came across my solution in other topics, but I ended up not using glass as touch surface. What works for me at the moment is EnL on the projector side, then 5mm acrylic then vellum as touchsurface and diffuser.
This improved much the situation, although blob tracking is still a bit hard at about 2 inch around the corners, where blobs get often lost (flickering). But this is a relatively minor issue since users are more often in the middle.

By the way what is the first app in your demo? Where did you get it?

Greg

Hey,

thanks man! I’m still hoping, that the upgrade to four cams will improve the results a lot, but we’ll see…

The first app is called “FluidSolver”. Have a look on this thread for the necessary files.

Update:

I “built” the first (and probably the prettiest ) part of my fiducial-set today:

Have a look on my blog for mor information.

Update:

The day before yesterday I finished my fiducial set for playing around with it.
More infos on my blog.

Now I need some software for testing the fiducials.
Any suggestions? Maybe a game or something like that?

What is the magnetic tape in your table used for?

Hey,

it’s used for holding the lid.

Nice vid cdog, your table setup works very well Keep up the good work

see the reactable on youtube , it seems to be the same idea as “fiducials” i don’t know what it is in french.

Hi Cdog

congrats for your proyect, it seems so clean and your video shows a good performance; just a couple of questions: why do you say that the table isn’t working very precise? what do you have in mind to solve it?

thanks in advance!

s3r3g0n - 30 July 2009 09:24 AM

see the reactable on youtube , it seems to be the same idea as “fiducials” i don’t know what it is in french.

Yeah I know. I got the idea of my “LED-cubes” from this video

Fernando - 07 August 2009 12:13 AM

Hi Cdog

congrats for your proyect, it seems so clean and your video shows a good performance; just a couple of questions: why do you say that the table isn’t working very precise? what do you have in mind to solve it?

thanks in advance!

Hey,

it’s not working very precise, because I’m using only one cam at the moment and the distortion of the fish-eye lens is too heavy. I’m planning to use four cams in the future, as soon as the multicam-driver is out and supports four cams at a time.