Hacker News Reader

Comment by jacobush | Hacker News Reader

Aren't really all cameras HDR capable with bracketing, i.e. shooting say 3 images or more with different settings.

Was thinking the same thing.

Essentially the person is saying they don’t own an SLR (digital or film) or a mirrorless camera, don’t own a smart phone, and don’t have a pocket point&shoot made in the last ten years or more.

You need to be able to change only shutter speed or ISO, while holding aperture constant. That's not a problem for phones, because they're almost always fixed aperture anyway. And of course any DSLR or mirrorless camera can do it. But some point-and-shoot cameras won't have this capability, they'll want to be fully automatic, not giving the photographer that specific control.

The many point-and-shoot cameras are also fixed-aperture (they use an NDF in bright light rather than adjusting the aperture).

Why not a single exposure? My camera (Nikon D750) shows up as having 14 stops of DR on DxOMark and IRRC a typical monitor in ambient condition is 8-9 stops. I haven't tested any of this though. Any in-camera JPG processing is applying a tone-mapping function to compress the range. Is the HDR label reserved for an image that has more range than the human eye can see and not necessarily the viewing device?

Depends on the style of HDR; if you want that post-appocolyptic look vs a just a well exposed shadows and protected highlights look. Shooting ETTR will allow for the shadows to get extra exposure while using the highlight recoverability of a RAW file to protect the highlight. Each camera sensor is different, so you have to practice with your camera to see how much you can push the exposure before unrecoverable clipping occurs. Obviously, the camera’s preview will looked overexposed, so people you show it to will think you’re crazy.

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.

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).

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.

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.

Reply on news.ycombinator.com