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I am trying to build a full RGB POV display. Unfortunately I purchased a neopixel strip (ws2812 144/m), and lately found that its data transfer rate is 800khz that is actually less for POV display. It is rather suggested to use APA102 based strip (adafruit dorstar) that is SPI based and works @6mhz. I am currently in India and I am not able to get a dotstar strip at a reasonable price. So, is there any possibility to use that strip to display at least an image (not some animation) properly. Please note I only intend to use 50-60 leds from that strip to keep the length within 18 inches. Thanks, Debojit

Debojit Kundu
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    This question makes more sense if we assume "POV" means "persistence of vision", not "point of view". But then how can a persistence of vision display have a single frame? Can you please edit your question to clarify? – Heath Raftery Feb 11 '20 at 20:48
  • @HeathRaftery I edited the question. by single frame I meant to say an image at least that is not changing over time. – Debojit Kundu Feb 12 '20 at 07:53
  • Ah makes sense now. Line update rate doesn't change whether the frame updates or not, so you're probably still stuck. @Mattman944's answer has some good guidance. – Heath Raftery Feb 12 '20 at 21:02

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No the WS2812 will not work well for Persistence of Vision applications.

enter image description here

My toy POV has over 100 updates per revolution. You can change my assumptions to see what other designs might be possible.

Also note that the WS2812 uses PWM to control the brightness. I don't know if the PWM frequency is fast enough to be unnoticeable. Although, you could run at full brightness.

Also see my answer to this question:

3D hologram fan display

Mattman944
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  • what is the babe minimum number of rotations per second to have a functional POV? I assume you considered 30 revs/sec. What is the minimum value? I mean would 10 rev/sec work? – Debojit Kundu Feb 12 '20 at 07:57
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    The image will be recognizable at much slower rates than 30 revs/sec, but at 10 revs/sec, the flicker will be annoying. You may need to build something and run some test to see if 10 revs/sec is usable for your application. – Mattman944 Feb 12 '20 at 08:39
  • Thanks for your guidance. I will try to procure an APA102c or SK9822 based led strip. Just one question - I am getting some SK9822 single leds, not in a strip. Can you suggest some easy way to connect them together to form a strip? – Debojit Kundu Feb 13 '20 at 18:55