Back to business. The weight of the eyes proved too much for the tiny springs, so I decided to encase the spring inside a sturdier one and on top of that I put a couple of coats of latex to hold it together and still be flexible. That proved an overkill. The eyes became too stiff and did not respond to the movement as expected. So I carved them from an ultralight foam, and gave the a few coats of liquid gesso. After sanding them they had just the right look and weight to be supported by the tiny springs.
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The focal point of the entire universe of the Creator is ultimately its creature. Regardless of the external appearance, which only a parent would love, the important thing is that which radiates from it and communicates its presence. This electronic soul is extremely simple yet fascinating. We started creating the tracking beacon using standard IR (infrared) LED's. We were having problems achieving the necessary brightness to be detected at a long distance. On top of that, since the creature moves around the stage wildly shaking every part of its body and sometimes lowering its head it was important that the beacon be visible in all circumstances. Adding the half-pong ball (sanded to paper thin) helped the angle spread of the light but we thought that it would cut the light considerably.
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And indeed our first tests confirmed that. So we bought the super-wide angle IR LED's in the hope of solving the angle problem and still retaining the strength of the light. (see the previous post on that here)
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Now comes the ignoramus part, which if we had done a little more research would have been avoided. All the webcams we tested have an internal filter that blocks IR, not exactly sure why (have not had a minute to explore that). So we proceeded to dismantle the lenses to remove such filters. (unfortunately we were so engrossed in doing so that I forgot to take pictures of the process!) This tested every sense and the steadiness of our hands, not to mention memorizing the order and orientation of every microlens. In fact, in the case of our wide-angle camera shown previously, after removing the IR blocker, we had to rearrange all 9 lenses and spacers in any imaginable way until we hit on the right one. Philip which has much better eyesight ended doing the final assemblies and it was nerve wracking to watch, almost like a brain surgeon removing a micro tumor.
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Well, then we were up for a big surprise, in fact we are still amazed at what we saw. First of all, the camera with the exposed film in place (to filter most of the visible light) not only saw the light, but it was as bright as pointing the camera to the sun! At this point we realized that both the standard LED's as well as the wide-angle ones work practically the same. You could turn the beacon even 180 degrees (in other words showing the back) and the camera would still see it very brightly.
But then we were in shock. By holding the IR device in our hand we observe something amazing. We could not only see the light going through our hand, we could see every vein as well! very much like x-rays, except we could not see the bones. Again, the surprise was such that I forgot to take pictures of this, but tomorrow I will. We even put the thing inside our mouth, but the cheeks were way to thin for the strength of the light. This immediately brought questions about the safety of this light which we had not considered.
So I have been reading papers and reports by organizations such as The International Commission on Non-Ionizing Radiation Protection, but have found little indication of danger at that level. However, although LED's are classified as IR-C are supposed to have a minimal penetration of the skin, while IR-A which is labeled as hazardous is said to penetrate the skin only a few millimeters. So something is odd here. More food for thought.
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