3 ms·

There are shaders to render such 'artifacts' programmatically at about a thousandth of the cost of what you describe. It could potentially be more accurate in t

There are shaders to render such 'artifacts' programmatically at about a thousandth of the cost of what you describe. It could potentially be more accurate in the way you describe it, but then what kind of blending mode do you use?

tobr 7y ago
I think you would first find the two closest brightness levels for each pixels, and blend appropriately between them - then simply use additive blending to composite all the pixels together. A naive approach would require compositing as many images as the number of pixels in the input signal, which seems extremely expensive, but in practice I’m sure you could optimize it quite a bit, as most of the area of each photo would be almost completely black.
- grenoire 7y ago
  If you can arrange lighting perfectly in your CRT studio, you could take only the difference against the all-off state. You could extract the pixel islands' positions and composite only these smaller chunks afterward. It could work out, but just not sure if it's worth all the hassle. It seems akin to the way you would do a stop-motion video, I suppose.
  - tobr 7y ago
    You would need to be in a pitch black room with only one pixel at a time lighting the scene. If you want additional light sources in the room they could be photographed and blended in with the same technique.
    - grenoire 7y ago
      "You could even set up a small still life around the monitor, and get accurate reflections and ambient light in the room." I think this would be a final additive pass after the pixel setup. Would also allow you to turn it off selectively... The more I think about it the more I want to try it out.
      - tobr 7y ago
        I think you would need to get the reflections in the same pass. It’s basically ray tracing in real life: emit light from a bunch of points (screen pixels), “calculate” how they bounce through the room (ie adjust the brightness of the corresponding photo), and combine them all into a single image.

tobr 7y ago

I think you would first find the two closest brightness levels for each pixels, and blend appropriately between them - then simply use additive blending to composite all the pixels together. A naive approach would require compositing as many images as the number of pixels in the input signal, which seems extremely expensive, but in practice I’m sure you could optimize it quite a bit, as most of the area of each photo would be almost completely black.

grenoire 7y ago
If you can arrange lighting perfectly in your CRT studio, you could take only the difference against the all-off state. You could extract the pixel islands' positions and composite only these smaller chunks afterward. It could work out, but just not sure if it's worth all the hassle. It seems akin to the way you would do a stop-motion video, I suppose.
- tobr 7y ago
  You would need to be in a pitch black room with only one pixel at a time lighting the scene. If you want additional light sources in the room they could be photographed and blended in with the same technique.
  - grenoire 7y ago
    "You could even set up a small still life around the monitor, and get accurate reflections and ambient light in the room." I think this would be a final additive pass after the pixel setup. Would also allow you to turn it off selectively... The more I think about it the more I want to try it out.
    - tobr 7y ago
      I think you would need to get the reflections in the same pass. It’s basically ray tracing in real life: emit light from a bunch of points (screen pixels), “calculate” how they bounce through the room (ie adjust the brightness of the corresponding photo), and combine them all into a single image.