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SlvrScoobie
03-18-2008, 08:38 AM
I know this is easy to do but.. the G/f and I get horrible results using Photoshops HDR merge feature with multi shots of bracketed exposures using Raw files. Always look awful, either washed out, or just muddy :P
Anyone got a tut. they found useful??

ride5000
03-18-2008, 09:07 AM
most of the "look" of hdr comes through the tone mapping of a hdr image back down to an ldr image. there are various methods of doing this but the typical "hdr" look is done through local adaptation, where pixels are compared to neighboring pixels within a configurable radius. photoshop will prompt you with a built-in tonemapper when you downbit from 32 or 16 to 8. if you flip around the various downbitting modes you'll see local adaptation is a choice.

typically true hdr images w/o tonemapping will look lousy when reproduced on an ldr medium like a crt or lcd, which backs up what you've observed.

that said i have started to become more familiar/comfortable with photomatix, a 3rd party hdr generator/tone mapper. something i've discovered so far is that ALL tone mappers are different in their rendering. some folks prefer other products like FDR tools.

you may find these forums useful:
http://forums.popphoto.com/camera/board?board.id=26
http://www.retouchpro.com/forums/hdr-hdri-tone-mapping/

in general i find pushing the bracketing to the overexposed side yields lower noise in the shadows during the tonemapping. not surprising, really, as it is an extension of the "expose to the right" mantra of digital capturing.

thomps6s
03-18-2008, 09:16 AM
Download the trial version of Photomatix

Colorblinded
03-18-2008, 09:41 AM
Everything ride5000 said is right, the "look" of HDR is mostly done in the tone mapping. For that matter it can be done to non-HDR images, a single file can be tonemapped and people will turn blue in the face calling it an HDR on a variety of community driven news sites (like Digg, reddit).

That's also where the trouble can arise in HDR, when you're making those local adaptations. If you push it too far you can effect reversal of tones, or result in very unreasonable and bizarre tonal changes where two objects end up having the same density if you will, even though they obviously shouldn't. Applied sparingly, and carefully, I think the tone-mapping effect can work quite well.

jacobsen1
03-18-2008, 09:48 AM
or you can read our very own HDR tutorial:
http://www.newschoolofphotography.com/?p=19
:wave:

Trees of My Time
03-28-2008, 10:08 PM
Download the trial version of Photomatix

If you do download and then later purchase Photomatix, bear in mind the fact that the "PHOTOMATIX" overwrite that is applied to your images cannot be erased with the installation of a serial number.

So if you have created images that you like, (and you will) make sure you save the bracketed shots so you can run the program again and retain your work!

Don

Markitos
03-29-2008, 12:08 AM
I do my HDRs in CS3, and the process is more complex than simply selecting "Merge to HDR." The best tutorial I have read was in last month's (or two months ago) British magazine Photography Monthly... If you still have questions, I can give you a more detailed answer tomorrow (right now it's late and I'm still at work and VERY tired).

ride5000
03-29-2008, 07:19 AM
If you do download and then later purchase Photomatix, bear in mind the fact that the "PHOTOMATIX" overwrite that is applied to your images cannot be erased with the installation of a serial number.

So if you have created images that you like, (and you will) make sure you save the bracketed shots so you can run the program again and retain your work!

Don

a handy way to avoid having to retain the bracketed exposures is to save the merged file as a 32 bit HDR image. then you can re-tonemap whenever you feel so inclined, with whatever your software of choice is.

Trees of My Time
03-29-2008, 08:51 AM
a handy way to avoid having to retain the bracketed exposures is to save the merged file as a 32 bit HDR image. then you can re-tonemap whenever you feel so inclined, with whatever your software of choice is.

Good point!

Calcvictim
03-31-2008, 01:02 PM
photomatix has a tutorial that explains what happens at every stage

http://www.hdrsoft.com/resources/tutorial_basic/index.html