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Comment by Frummy | Hacker News Reader

I was in a butterfly house, and closeup photos removed the legs of the butterflies to keep only the wings lol.

Looks like you are using the portrait effect to blur the background. The phone just assumed the legs were part of the background. Happens to hair as well.

That will be the denoising. Legs are thin and can easily be interpreted as noise - especially when using digital zoom and dim light so there are very few pixels and each pixel is very noisy.

More like the poor masking algorithm interpreted the legs as background and blurred them.

Denoising is often great, but sometimes it really destroys details. It is basically impossible to capture a snowy day (or heavy rain) with a digital camera. The denoiser will remove 90% of the snowflakes. Analog cameras, by contrast, remove nothing.

Interestingly, some phones now use a model of the camera sensor to detect how much noise there 'should' be (based on temperature, age of sensor, test results of the specific sensor from the factory, exposure time and light levels). They then only remove that much noise, hopefully leaving snow.

Every other phone just has an algorithm to estimate how much noise is in an image by sampling a few patches - and that will remove snow.

Interesting. Do you know which phones have this feature?

My A7ii does that just fine and it's pretty old now.

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