Google explains how the Live HDR+ feature on the Pixel 4 and 4a works

 Pixel 4

The new Pixel 4a supports Live HDR+ and Dual Exposure, features first introduced with the Pixel 4 (note that these won’t be backported to older devices). The tech giant published a detailed blog post explaining how the two features work. First, what is Live HDR+? It shows a real time preview of what the final HDR+ photo will look like. Note that this is just a preview derived using a different algorithm. The real HDR+ takes 3-15 underexposed photos (to reduce noise), aligns them and merges them. After the merge, tone mapping is applied to produce the final photo where details in...

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