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Comment by rocqua | Hacker News Reader

They need some method for keeping the camera in the same spot, and (roughly) pointing in the same direction.

A smartphone without a dedicated funcion probably has too much delay between shots for HDR. Same for point-and-shoots without a tripod mount.

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A 'poor persons' HDR can be done with ONE good photo. Load it into a decent photo editor, and adjust the exposure down two stops and save it, then repeat again but up 2 stops. Now with the 3 copies, run it through a HDR generator. Not as good as bracketing directly in the camera, but can yield acceptable results.

No. This will give the visual effect of HDR (which many think is something to be avoided - HDR should be a tool, not a style), but does not increase the actual dynamic range.

True, but based on the fact that hardly anyone has actual HDR capable displays, the net effect of the output is mostly the same.

It does.

My RAW Images has a higher dynamic range than the final image shows without any HDR feature.

You only put back what was already there and 'lost'.

That only works if you're shooting RAW. And even then all you've accomplished was a convoluted process to achieve the exact same thing you'd get in Lightroom by adjusting the Blacks and Whites sliders, and dragging the ranges horizontally in the histogram.

That does not invalidate my original statement.

I would argue that the end result should look slightly different.

But you do use more of your dynamic range

Really, if you are going down that road I prefer manually blending the different exposures in Photoshop. 5 years ago, that is how I dealt with bracketed exposures as well. Back then HDR still had a very definite look which I really tried to avoid.

Even if you don't have/can't use a tripod , software stabilization is pretty good for handheld use. And there are a few ways you can pull that with OpenCV, so it's not that expensive editing software is involved (of course, Photoshop has it, and in a "photographer friendly way").

Stabilization deals with orientation. Location cant really be corrected for based on a 2D image.

Yes -- but it still works fine for the common distortions that a handheld camera introduces (assuming you don't go into very large time spans).

I've combined hand held bracketed shots. There are problems at the edges of things due to slight shifts in location and parallax but this can be handled in photoshop and HDR (I used to use Photomatix) does a good job at removing ghosting and edge artifacts.

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