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0 pointsvilhelm_s11y ago0 comments

I think it should work for shadows also? Adding together 10 photos taken at 1/100s should give the same amount of light as one photo taken at 1/10s.

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sp33211y ago

But if each photo is just black because it's underexposed, then adding them together only gives you black.

vilhelm_sOP11y ago

If the pixels were literally black that would be the case, but even on very underexposed pictures I don't think that ever happens. There's still photons on the sensor, it's just that they are swamped by the noise. Like, most DSLRs nowadays capture 12-bit values, which suggests you would have to underexpose by something on the order of 12EV to truncate the output to zero.

CHY87211y ago

Yes, and that is very, very possible. In any case, doing that would give you some relatively painful quantisation error, which is why the HDR approach works better.

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sp33211y ago

But if each photo is just black because it's underexposed, then adding them together only gives you black.

vilhelm_sOP11y ago

CHY87211y ago

Yes, and that is very, very possible. In any case, doing that would give you some relatively painful quantisation error, which is why the HDR approach works better.

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