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Comment by XCSme | Hacker News Reader

What about taking 3 photos while quickly changing the filter (e.g. filters are something like quantum dots that can be turned on/off)?

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Olympus and other cameras can do this with "pixel shift": it uses the stabilization mechanism to quickly move the sensor by 1 pixel.

https://en.wikipedia.org/wiki/Pixel_shift

EDIT: Sigma also has "Foveon" sensors that do not have the filter and instead stacks multiple sensors (for different wavelengths) at each pixel.

https://en.wikipedia.org/wiki/Foveon_X3_sensor

> What about taking 3 photos while quickly changing the filter

Works great. Most astro shots are taken using a monochrome sensor and filter wheel.

> filters are something like quantum dots that can be turned on/off

If anyone has this tech, plz let me know! Maybe an etalon?

https://en.wikipedia.org/wiki/Fabry%E2%80%93P%C3%A9rot_inter...

> If anyone has this tech, plz let me know!

I have no idea, it was my first thought when I thought of modern color filters.

That's how the earliest color photography worked. "Making color separations by reloading the camera and changing the filter between exposures was inconvenient", notes Wikipedia.

I think they are both more asking about 'per pixel color filters'; that is, something like a sensor filter/glass but the color separators could change (at least 'per-line') fast enough to get a proper readout of the color in formation.

AKA imagine a camera with R/G/B filters being quickly rotated out for 3 exposures, then imagine it again but the technology is integrated right into the sensor (and, ideally, the sensor and switching mechanism is fast enough to read out with rolling shutter competitive with modern ILCs)

Works for static images, but if there's motion the "changing the filters" part is never fast enough, there will always be colour fringing somewhere.

Edit or maybe it does work? I've watched at least one movie on a DLP type video projector with sequential colour and not noticed colour fringing. But still photos have much higher demand here.

You can use sets of exotic mirrors and/or prisms to split incoming images into separate RGB beams into three independent monochrome sensors, through the same singular lens and all at once. That's what "3CCD" cameras and their predecessors did.

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