5 ms·

The Skiatron and Early Dark Trace CRTs

42 points by masswerk 3y ago

xattt 3y ago
What kills me is there’s no Skiatrons to be seen, not on YouTube nor in any museums.
- anfractuosity 3y ago
  The youtube video in the article shows a very short clip of a radar screen updating. Would be cool to see one in person if there's any still around. I just found https://tubetime.us/index.php/2014/06/09/p10-dark-phosphor-the-skiatron/ https://tubetime.us/index.php/2014/06/09/p10-dark-phosphor-t... too.
  - tubetime 3y ago
    and i still have the tube! at some point i should make a YouTube video about it.
    - xattt 3y ago
      For the love of god, please do. You’ll be capturing disappearing history, and roll in some YouTube dough.
nathancahill 3y ago
The myth that carrots are good for your eyes was introduced by the British to explain how the RAF pilots were able to keep downing planes, even at night, in an effort to keep radar a secret.
actionfromafar 3y ago
I read somewhere about a radar system which exposed film reels, developed them in a continuous process, and displayed new images with a film projector every few seconds. I wanna say it was British, but maybe it was American. Can’t find a reference anywhere anymore. Cool thing was, you’d get a log “for free” because you still had all of that film you could replay.
- masswerk 3y ago
  Gustav Wikkenhauser mentions this briefly: > The tube provides immediately a visible record which can be kept on in detail at leisure. This record can, of course, be traced on paper or photographed with a simple camera. (…) For most of the applications it was found that direct observations were sufficient. [0] https://www.cdvandt.org/Blauschrift-Roehre.pdf https://www.cdvandt.org/Blauschrift-Roehre.pdf Wikipedia includes a passage on rapid film recording and development as an alternative (based on fluorescent CRTs): > Even the use in radar was not widespread; looking for an even larger format system with better properties, the RAF turned to the Photographic Display Unit, a system that took a photograph of the display, rapidly processed it, and then projected it through a modified movie projector. Even with this complexity, it was faster than the skiatrons, producing a new image every 15 seconds] while the skiatron units were typically longer due to the erasure process. [1] https://en.wikipedia.org/wiki/Skiatron https://en.wikipedia.org/wiki/Skiatron (Note: provided the short clip in that film, I cannot see how the argument really adds up. I guess, the log and analysis aspect was important. Moreover, I assume, as the size of the projection exceeds what is possible with direct projection and you have to opt for intermediate steps anyway, "conventional" CRTs were preferable for any photographic process because of their contrast properties.) For more on the Photographic Display Unit, see: [2] https://en.wikipedia.org/wiki/Photographic_Display_Unit https://en.wikipedia.org/wiki/Photographic_Display_Unit
  - nickloewen 3y ago
    Fantastic! The comment you're replying to sent me looking for references, too. The closest I found was this article, which mentions an installation at RAF Truleigh Hill: https://www.shorehambysea.com/raf-truleigh-hill/ https://www.shorehambysea.com/raf-truleigh-hill/ "This device was a continuous photographic process which filmed the radar screen, processed the film and projected the image onto a glass screen within a very few seconds." (I wonder whether something like the Eidophor system that NASA used for mission control would have been another option? https://en.wikipedia.org/wiki/Eidophor https://en.wikipedia.org/wiki/Eidophor)
    - masswerk 3y ago
peter_d_sherman 3y ago
Related: https://en.wikipedia.org/wiki/Scotophor https://en.wikipedia.org/wiki/Scotophor >"A scotophor is a material showing reversible darkening and bleaching when subjected to certain types of radiation. The name means dark bearer, in contrast to phosphor, which means light bearer.[1] Scotophors show tenebrescence (reversible photochromism) and darken when subjected to an intense radiation such as sunlight."
- masswerk 3y ago
  Thanks! (It's actually linked in the article.)
  - peter_d_sherman 3y ago
    I had not known that there were materials called 'Scotophors', nor what their properties were, prior to reading the article, so I thought it apropos to highlight this point by requoting Wikipedia's comments about these materials, here... I assume you're the author of this article? It's an excellent article! Well written... And I learned some stuff I didn't know previously. So, thank you for writing this excellent article!
    - masswerk 3y ago
      Yes, I'm the author. I didn't know anything about this before seeing those 2.5 secs in the video, going, hold on, what is this? So I went on to find out, and thought it may be interesting to share. (Because, well, as I have now found out, what would be the point in sitting on this piece of information? :-) )

42 points by masswerk 3y ago

xattt 3y ago

What kills me is there’s no Skiatrons to be seen, not on YouTube nor in any museums.

anfractuosity 3y ago
The youtube video in the article shows a very short clip of a radar screen updating. Would be cool to see one in person if there's any still around. I just found https://tubetime.us/index.php/2014/06/09/p10-dark-phosphor-the-skiatron/ https://tubetime.us/index.php/2014/06/09/p10-dark-phosphor-t... too.
- tubetime 3y ago
  and i still have the tube! at some point i should make a YouTube video about it.
  - xattt 3y ago
    For the love of god, please do. You’ll be capturing disappearing history, and roll in some YouTube dough.

nathancahill 3y ago

The myth that carrots are good for your eyes was introduced by the British to explain how the RAF pilots were able to keep downing planes, even at night, in an effort to keep radar a secret.

actionfromafar 3y ago

I read somewhere about a radar system which exposed film reels, developed them in a continuous process, and displayed new images with a film projector every few seconds. I wanna say it was British, but maybe it was American. Can’t find a reference anywhere anymore. Cool thing was, you’d get a log “for free” because you still had all of that film you could replay.

masswerk 3y ago
Gustav Wikkenhauser mentions this briefly: > The tube provides immediately a visible record which can be kept on in detail at leisure. This record can, of course, be traced on paper or photographed with a simple camera. (…) For most of the applications it was found that direct observations were sufficient. [0] https://www.cdvandt.org/Blauschrift-Roehre.pdf https://www.cdvandt.org/Blauschrift-Roehre.pdf Wikipedia includes a passage on rapid film recording and development as an alternative (based on fluorescent CRTs): > Even the use in radar was not widespread; looking for an even larger format system with better properties, the RAF turned to the Photographic Display Unit, a system that took a photograph of the display, rapidly processed it, and then projected it through a modified movie projector. Even with this complexity, it was faster than the skiatrons, producing a new image every 15 seconds] while the skiatron units were typically longer due to the erasure process. [1] https://en.wikipedia.org/wiki/Skiatron https://en.wikipedia.org/wiki/Skiatron (Note: provided the short clip in that film, I cannot see how the argument really adds up. I guess, the log and analysis aspect was important. Moreover, I assume, as the size of the projection exceeds what is possible with direct projection and you have to opt for intermediate steps anyway, "conventional" CRTs were preferable for any photographic process because of their contrast properties.) For more on the Photographic Display Unit, see: [2] https://en.wikipedia.org/wiki/Photographic_Display_Unit https://en.wikipedia.org/wiki/Photographic_Display_Unit
- nickloewen 3y ago
  Fantastic! The comment you're replying to sent me looking for references, too. The closest I found was this article, which mentions an installation at RAF Truleigh Hill: https://www.shorehambysea.com/raf-truleigh-hill/ https://www.shorehambysea.com/raf-truleigh-hill/ "This device was a continuous photographic process which filmed the radar screen, processed the film and projected the image onto a glass screen within a very few seconds." (I wonder whether something like the Eidophor system that NASA used for mission control would have been another option? https://en.wikipedia.org/wiki/Eidophor https://en.wikipedia.org/wiki/Eidophor)
  - masswerk 3y ago

peter_d_sherman 3y ago

Related: https://en.wikipedia.org/wiki/Scotophor https://en.wikipedia.org/wiki/Scotophor >"A scotophor is a material showing reversible darkening and bleaching when subjected to certain types of radiation. The name means dark bearer, in contrast to phosphor, which means light bearer.[1] Scotophors show tenebrescence (reversible photochromism) and darken when subjected to an intense radiation such as sunlight."

masswerk 3y ago
Thanks! (It's actually linked in the article.)
- peter_d_sherman 3y ago
  I had not known that there were materials called 'Scotophors', nor what their properties were, prior to reading the article, so I thought it apropos to highlight this point by requoting Wikipedia's comments about these materials, here... I assume you're the author of this article? It's an excellent article! Well written... And I learned some stuff I didn't know previously. So, thank you for writing this excellent article!
  - masswerk 3y ago
    Yes, I'm the author. I didn't know anything about this before seeing those 2.5 secs in the video, going, hold on, what is this? So I went on to find out, and thought it may be interesting to share. (Because, well, as I have now found out, what would be the point in sitting on this piece of information? :-) )