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XCSmeyesterday at 11:56 PM4 repliesview on HN

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


Replies

lidavidmtoday at 12:41 AM

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

itishappytoday at 12:05 AM

> 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...

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MarkusWandeltoday at 12:18 AM

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.

numpad0today at 1:26 AM

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.