It's also mentioned in another comment and (I think) the video about how it wouldn't work in chocolate. As it works creating oxide layers, not a diffraction structure:
If you try it directly on PMMA it won't create a diffraction structure, but a kinda slightly melted surface. I don't know if etching would be possible with enough precision on PMMA.
If you do it on steel and use it as a mold to pour (?) PMMA, as people do with chocolate and diffraction grates on plastic, there's no structure to transfer.
I notice a similar 'holographic' effect when coloring titanium a couple weeks back, and experimented with getting them dialed in along the same lines as this video. I didn't have nearly as much success, despite the underlying physics being similar. My guess is that the much lower thermal conductivity of titanium causes a lot more smudging than on stainless, which makes the grating effect less pronounced.
One interesting thing I noted with Ti is that satin finished Ti (media blasted with 500 grit glass media) won't take a color from electrocoloring, but will from MOPA laser coloring. Not nearly as nice as polished Ti, but still there. Given that they are such similar processes (growing a set thickness oxide layer), its somewhat surprising to see different results.
I guess I'm going to have to experiment on some polished 304.
I'm confused by the authors description of holograms and my own understanding. He starts to go down a path of holographic "pixels," but whai I know about holograms is that the holographic image doesn't have such a concept - the image is delocalized.
There have been some successful attempts at handmade holograms[1] that I wonder how the video creator could adapt.
I suspect that the idea is that the simple way to etch a hologram in the surface is to have a set of holographic picture elements(pixels) where each element hologram would get etched for each pixel in the source image.
It also sounds like this was a minor side experiment and found not to work as expected so not much further effort was put into it.
I think he's thinking like lenticular images which are often described as 'holograms', since the apparent color changes with the viewing angle like with the lenticular images.
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[ 53.1 ms ] story [ 1009 ms ] threadIt's also mentioned in another comment and (I think) the video about how it wouldn't work in chocolate. As it works creating oxide layers, not a diffraction structure:
If you try it directly on PMMA it won't create a diffraction structure, but a kinda slightly melted surface. I don't know if etching would be possible with enough precision on PMMA.
If you do it on steel and use it as a mold to pour (?) PMMA, as people do with chocolate and diffraction grates on plastic, there's no structure to transfer.
I notice a similar 'holographic' effect when coloring titanium a couple weeks back, and experimented with getting them dialed in along the same lines as this video. I didn't have nearly as much success, despite the underlying physics being similar. My guess is that the much lower thermal conductivity of titanium causes a lot more smudging than on stainless, which makes the grating effect less pronounced.
One interesting thing I noted with Ti is that satin finished Ti (media blasted with 500 grit glass media) won't take a color from electrocoloring, but will from MOPA laser coloring. Not nearly as nice as polished Ti, but still there. Given that they are such similar processes (growing a set thickness oxide layer), its somewhat surprising to see different results.
I guess I'm going to have to experiment on some polished 304.
There have been some successful attempts at handmade holograms[1] that I wonder how the video creator could adapt.
1. http://amasci.com/amateur/holo1.html
It also sounds like this was a minor side experiment and found not to work as expected so not much further effort was put into it.
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But it would show me the video using Chromium, without an account configured.