I got home tonight to find a parcel of tracking markers waiting for me - just in time for their first outing this weekend:

Once we’ve done this shoot this weekend, I should have a lot more for you - hopefully this week’s lull won’t continue for too long.
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May 6th, 2005 at 16:46
Im curious about your trackers, are they IR trackers for mocap ? or are you going to use them for matchmoving ? i have heard mixed reviews on that.
where did you get them ?
thnx
May 6th, 2005 at 16:54
They are normal red LED markers for matchmoving. They give a bit more of a flare than I’d have liked (I might try putting some kind of ND gel on them to dim them down a bit), but they do work pretty well.
A friend of mine who’s an electronic engineer made them for me. If anyone’s interested, I could ask if he’d be willing to do more for other people….
May 6th, 2005 at 17:12
I heard that about them, surely there must be a way to filter the LEDs so they dont flare. good luck with the gel.
Im pretty new to matchmoving but I was under the impression that the tracker takes into account changes in scale and rotation as well as position. how can you get that information from tracking a point ?
its nice to have a friend with a soldering iron.
I am also in a low budget world right now so I couldnt really compensate your friend for his work. I would take a stab at it myself tho, looks pretty straight forward. are the LEDs wired directly to the batteries? or is there a resistor there somewhere to prevent burnouts ?
May 8th, 2005 at 12:25
dak, you need to track more points to get info for the rotation and scale… a single point is enough for tracking 2d position… for matchmoving a lot more points are required…at least three (or four maybe - as in a cube)… So…with 1 tracker you can have 2d motion (x,y axis), with 2 you get 2d motion, rotation and maybe size (still in 2d)…then with more than 3 you can go for 3d matchmoving..but it’s important on how they are placed…
I haven’t done much matchmobing so this came off the top of my head, so if I wrong, somebody please correct me ^_^
May 9th, 2005 at 15:37
There is a resistor in there. It is (from memory) a 100 ohm resistor.
The LED’s are 5000mcd - bright enough to be used in daylight.
The whole item - including batteries and labour costs about £2.35 each.
Obviously you would probably be able to make them for less, you can pick up most of the components from Maplin or RS or farnell.
If you are interested drop me a line. I can also supply the components seperately if anyone is interested.
May 9th, 2005 at 15:42
Or you can just get in touch with him yourself^
Didn’t know you actually checked this place out, Rob! Good to see you on here.
Your e-mail address hasn’t come through to be publicly visible on here, but I assume people could get in touch with you via your website…?