Opinion or examples. Bracket during processing?

[35mm4me]

Is the result the same if you get your exposures during processing of one image shot at the proper exposure? And then load bracketed images? Or do you have to bracket your images at time of shooting.

Thanks

 

[cgipson1]

You are much better off bracketing at the time of exposure. There is no (or very little) information in the blown whites and dead blacks in a single image (which will occur if the subject has a high enough dynamic range to need HDR in the first place. That is why you expose to cover a much wider dynamic range than one shot will give you.

Fake HDR's lack dynamic range... and people often try to hide it with tonemapping... which can look ghastly!

 

[ShooterJ]

You mean shooting one RAW image, for example .. then creating additional images from that one at different exposures to merge later?

 

[ShooterJ]

I'd never really considered trying that. Pretty easy to bracket a shot in camera. I think it's probably faster than trying to edit for different exposures later on anyway.

 

[cgipson1]

Even a raw file will not contain enough information to cover the exposures needed on a wide dynamic range subject....

Quote from> HDR images in photography - About Dynamic Range, Tone Mapping and HDR Imaging for Photography < HDRSoft HDR Software FAQ (one would think that an HDR software manufacturer would know this, right?)

Can't I just create the exposures from one RAW file?

Not really. Your RAW file contains data captured by the sensors for only one exposure. The total dynamic range you can reconstruct from one photo converted with different exposure settings can never be more than the dynamic range captured by your camera, and this is rather limited (see above). When you are using only one exposure to capture the scene, your RAW file is already your HDR image. Converting the RAW file to images with different exposure levels is a bit like slicing the dynamic range of the RAW into several parts. Combining the parts back into an HDR image will at best re-produce the dynamic range of the initial RAW file.

That said, if you are using a good RAW converter to derive fake exposures from a single RAW file, you will probably notice that the HDR image created from the fake exposures shows more dynamic range than the pseudo-HDR image obtained by converting the single RAW file directly. This is because your RAW converter includes a good noise reduction function, and this has an important effect on the dynamic range. You RAW converter may also include the ability to continue to retrieve highlights details when one or two of the color channels have already reached saturation.

So, a good RAW converter includes functions designed to optimize the dynamic range retrieved from the raw sensor data, but this does not change the fact that the dynamic range of a RAW file is limited to one exposure only. Unless the dynamic range of your scene is low, you will need to take more than one exposure to create an HDR image of the scene.

 

[Derrel]

Yes...there are many tutorials on taking ONE, single RAW image, and making a conversion optimized for the highlights, and one for the shadows, and then blending them in Photoshop, and when done right, the results can look pretty good. A few years ago, before Photomatix was developed, it was considered a pretty standard operating procedure. I have seen some simply outstanding images done this way.

This method is only as good as the skill of the practitioner; like so many things, it takes actual SKILL to make this work right.

 

[amolitor]

I do this all the time, pulling extra highlight information from the RAW and blending. It's a good trick, and one everyone should definitely have in their bag.

I suspect that it's much much easier in b&w than in color, but since I pretty much mostly do b&w, it's pretty much SOP for me. It's not HDR, though. It's Less Low Dynamic Range, LLDR.

 

[cgipson1]

This is an interesting article on Dynamic Range extraction on a single Raw File...

RAW dynamic range extraction - PanoTools.org Wiki

 

[35mm4me]

Here is why I ask. I am about to head to California and will no doubt be taking some coastal shot, My camera only brackets manually take a shot change exposures and so on. With waves and surf there is too much time in-between each shot?

 

[ShooterJ]

Being so easy to bracket, though.. what's the advantage? Why give myself more work in post when the camera can fire off the exposures I need right there?

 

[cgipson1]

Here is why I ask. I am about to head to California and will no doubt be taking some coastal shot, My camera only brackets manually take a shot change exposures and so on. With waves and surf there is too much time in-between each shot?

See the article I linked to above.. for fake HDR (sometimes necessary when there are moving objects in the shot (unless you are really good at de-ghosting), or if you want something really random (like waves) sharp with increased dynamic range) This is a good way to go...

 

[ShooterJ]

Here is why I ask. I am about to head to California and will no doubt be taking some coastal shot, My camera only brackets manually take a shot change exposures and so on. With waves and surf there is too much time in-between each shot?

Ah.. I see. I'm looking at it from the perspective of AEB. With that feature I've never thought of trying to work with a single image for HDR.

 

[cgipson1]

Being so easy to bracket, though.. what's the advantage? Why give myself more work in post when the camera can fire off the exposures I need right there?

For static subjects.. I highly recommend multiple exposures (AEB)... but what if you have a moving object that has a high dynamic range that can't be captured with more than one image due to the difficulty of multiple ghosts. Like a shot of a Merry Go Round at night.. and you don't want blur.. you want it stopped, and sharp (with a wide dynamic range). Multiple images are very difficult to do that with.. (it can be done.. but a lot of Post work is required, getting rid of ghosts). Far easier to do a fake HDR with a single RAW... it won't have the same range, but will be much wider than a single Jpeg could capture.

 

[ShooterJ]

Being so easy to bracket, though.. what's the advantage? Why give myself more work in post when the camera can fire off the exposures I need right there?

For static subjects.. I highly recommend multiple exposures... but what if you have a moving object that has a high dynamic range that can't be captured with more than one image due to the difficulty of multiple ghosts. Like a shot of a Merry Go Round at night.. and you don't want blur.. you want it stopped, and sharp. Multiple images are very difficult to do that with.. (it can be done.. but a lot of Post work is required). Far easier to do a fake HDR with a single RAW... it won't have the same range, but will be much wider than a single Jpeg could capture.

That makes sense. Even using AEB that makes sense. Something to play with just for the hell of it. I may have to give some of it a try.

 

[OliverH]

There's no point in artificially generating multiple photos of different exposures from the same original data. Information that's not present in the original photo cannot be magically introduced my making that same photo darker or brighter.

If you have a RAW photo with more than 8 bit of dynamic range, it's best to export it in a 16-bit or higher file format (16-bit TIFF seems to be most commonly used for that purpose). Then you can load that photo into your tonemapping software and tonemap it into an 8-bit dynamic range.