3 ms·

I assume this is the project you mean? - https://ofersp.github.io/digital_needle/ https://ofersp.github.io/digital_needle/ it's a shame there doesn't seem to be

I assume this is the project you mean? - https://ofersp.github.io/digital_needle/ https://ofersp.github.io/digital_needle/ it's a shame there doesn't seem to be sourcecode. Very cool though. You can also get laser turntables - https://en.wikipedia.org/wiki/Laser_turntable https://en.wikipedia.org/wiki/Laser_turntable which look intriguing I'm rather curious about these microscopes - https://matesy.de/en/products/magnetic-field-visualization/magview https://matesy.de/en/products/magnetic-field-visualization/m... which can visualise magnetic fields, they're very expensive though.

userbinator 4y ago
If I remember correctly, laser turntables were not popular because they also reproduced all the fine dust on the surface of the disk.
- iforgotpassword 4y ago
  Yep. Every tiny dust particle makes an audible pop, while an actual stylus would've just pushed it out of the groove.
  - interestica 4y ago
    So laser turntable needs a leading 'dust plow' ?
    - morcheeba 4y ago
      That sounds good! Two other solutions: - low pass filter. Assuming the dust is small compared to the expected movement in the groove, you can filter it out electornically. - dust detector. Nikon had a cool 35mm scanner... instead of RGB, it had an additional IR layer at an angle just to detect dust. So, automated dust removal tools knew if a black spot in an image was supposed to be there, or if it was actually dust. Here, extra optics would know if the laser was reading dust and could mute/filter the sound during that time.
      - interestica 4y ago
        Interesting ideas! The 'dust detector' is 'Digtal ICE' that you'll sometimes see labeled on scanners. (https://en.wikipedia.org/wiki/Digital_ICE https://en.wikipedia.org/wiki/Digital_ICE)
  - pizza 4y ago
    Someone should try doing a dsp+ml hybrid filter that takes both the optical signal and the generated audio into account to filter out the crackling

userbinator 4y ago

If I remember correctly, laser turntables were not popular because they also reproduced all the fine dust on the surface of the disk.

iforgotpassword 4y ago
Yep. Every tiny dust particle makes an audible pop, while an actual stylus would've just pushed it out of the groove.
- interestica 4y ago
  So laser turntable needs a leading 'dust plow' ?
  - morcheeba 4y ago
    That sounds good! Two other solutions: - low pass filter. Assuming the dust is small compared to the expected movement in the groove, you can filter it out electornically. - dust detector. Nikon had a cool 35mm scanner... instead of RGB, it had an additional IR layer at an angle just to detect dust. So, automated dust removal tools knew if a black spot in an image was supposed to be there, or if it was actually dust. Here, extra optics would know if the laser was reading dust and could mute/filter the sound during that time.
    - interestica 4y ago
      Interesting ideas! The 'dust detector' is 'Digtal ICE' that you'll sometimes see labeled on scanners. (https://en.wikipedia.org/wiki/Digital_ICE https://en.wikipedia.org/wiki/Digital_ICE)
- pizza 4y ago
  Someone should try doing a dsp+ml hybrid filter that takes both the optical signal and the generated audio into account to filter out the crackling