Probably stupid, Can you do this?

And they would be better if you took 3 exposures from the camera...

Not true.

I dont really consider the "exposure" able to be adjusted, sure you can make it lighter/darker, but that doesnt change how much light from shadows are received on the sensor...

If you under or over expose in photoshop, its not the real thing, even if its close, its still not.

You are darkening the highlights and brightening the highlights bascally speaking, you get some noise out of doing that....

If you do it in the camera you get the real pictures, not a photoshopped picture that loses quality when you mess with levels/exposure/curves etc...

I don't think you understand what a RAW file is since you're mentioning using photoshop levels and curves to create the images. None of my HDRs have ever been touched by photoshop. I'm simply creating 3 exposures from 1 RAW file.. yes a RAW file in which there is no loss of data while adjusting exposure, then exporting to photomatix. I've done HDRs with 3 seperate photographs and with 1 RAW file and I've never seen a difference in quality. One RAW file just provides many more options as shown in my example above.
 
Since when is it a "fake" HDR? It's 3 images with different exposures. I believe you're confused on the definition of an HDR.

Since when could you change your sensor's dynamic range in post?

It's not HDR if it's all from one source file. All you're doing is complex curves and levels adjustments.

HDRs work best with High Dynamic Ranges (hence the name). So if you're taking a shot and you've blown the highlights and clipped the shadows, you can't rescue that in post (which is what you'd be doing with one image).

If you take three separate exposures: one for the shadows, one for the mid-tones, and one for the highlights (you don't even have to only take one for each; take as many as you feel necessary), then combine them, you've captured far more of the scene's range of light, but are displaying it in the dynamic range of your monitor/output device.

Try capturing a scene like that with one file, then saving three exposures. You won't get the detail; you can't rescue pure white/black areas.
 
thanks for the info i think im actaully getting the hang of it now..

i got photomatix and ill run through some photos tomorrow
 
Ok... I gave it a shot using the exposure on my camera... cheesy p&s... but do I have the right idea? It was dusk and windy so I had to find something not windy to take 3 separate shots.

Here's the original
2758728317_d8eaa646b4_o.jpg



And the HDR
2758728325_e2562d2877_o.jpg
 
And the HDR
2758728325_e2562d2877_o.jpg


See how the sky there is blue? Try getting that from a white blown-out sky in one image without making everything else dark to begin with, and very noisy and lacking in detail after processing.

You're definitely getting the hang of it there. It doesn't look over-done, which is always something I appreciate.
 
The "fake HRDIs" you guys are talking about are actually the results of a process called "Tone Mapping". HDR in photography circles is often ALSO tone mapped and therein lays the confusion. :D BTW, the I in HDRI just stands for "Image".

So there are three different basic types of images with and without tone mapping :

8 bpp JPeg
12/14 bpp RAW
16/32 bpp HDR

8 bpp JPeg - tone mapped
12/14 bpp RAW - tone mapped
16/32 bpp HDR - tone mapped.

The top three if done correctly should look identical unless you have an HDR monitor :D The 12 or 14 bit per pixel RAW images are able to display at a wider range of exposures than the 8bpp JPEG. Like the Jpeg however, it only displays at one of them (without tone mapping). The 16 and especially the 32 bpp are capable of displaying a MUCH larger range of exposures than with the RAW or the JPG but again only one exposure level can be displayed to your 6bit or 8bit LCD monitor without tone mapping it. Once any of them are tone mapped and saved as a JPG they are no longer RAW or HDR files.

The bottom three can look similar but obviously there will a be greater range from which to tone map with. A good example is Post #17 above. Look at the cloud in the center. See the missing detail in the cloud of the bottom "fake HDRI"?

PS: The 8 bpp images don't have to be JPG. I just used that as it's commonly associated format for 8bpp camera images.
 
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again nynfortoo is (what i think is) correct.

Those images that yous have posted, the single untouched jpegs.. you can pull out the same detail from the shadows and highlights from that one image, not to mention the colour, too.. there's no 'extended' dynamic range being pulled doing 3 seperate 'exposures' from one RAW file.

Say you take a normal exposure, the sensor will capture say 8 stops of light - that's all you have, all you're doing then is making it lighter/darker. tone-mapping.

When you take 3 RAW's say 2 stops apart you'll get this sort of range (say your sensor gets 8 stops for ease of numbers here):

RAW 1 = -4 to +4 stops (mid)
RAW 2 = -6 to +2 stops (shadows)
RAW 3 = -2 to +6 stops (highlights)

All in all you've extended your dynamic range as you've now captured -6 to +6 stops, 12 stops.. that's 4 more stops than your sensor could have.. that's extending your dynamic range. My example is rough but that's the general idea.
 
Yes nynfortoo is spot on.

One RAW used to create an 'HDR image' could be named fake, bacuase it is NOT a true HDR image, it is simply tone mapped.

Im affraid the use of HDR has been diluted over the last few years. Images above like the helicopter form Syndac, are fun uses of tone mapped images, but the result as shown can easily be created without blending exposured at all.. there is simply no need for it.

Now, take a scene with a dramatic light difference, i.e. the inside of a dark church with natural light coming through the stained glass windows. The 3 files from one RAW technique would not cover the dynamic range well enough. 3 (or preferably more) different exposures however, would.

This is the problem with many HDR 'tests' they are usually done of scenes which do not require HDR in the first place.
 
This is the problem with many HDR 'tests' they are usually done of scenes which do not require HDR in the first place.


I actually happen to have one that would, unfortunately it's on film, but it's an easy location to get to and reshoot. I just might find my self out there doing just that at some point in the near future, just because I am curious to know if I can pull off an HDR.
 
Yes nynfortoo is spot on.

One RAW used to create an 'HDR image' could be named fake, bacuase it is NOT a true HDR image, it is simply tone mapped.

Im affraid the use of HDR has been diluted over the last few years. Images above like the helicopter form Syndac, are fun uses of tone mapped images, but the result as shown can easily be created without blending exposured at all.. there is simply no need for it.

Now, take a scene with a dramatic light difference, i.e. the inside of a dark church with natural light coming through the stained glass windows. The 3 files from one RAW technique would not cover the dynamic range well enough. 3 (or preferably more) different exposures however, would.

This is the problem with many HDR 'tests' they are usually done of scenes which do not require HDR in the first place.

You're still confusing HDR with tone mapping though. If it's in JPEG format it's not HDR no matter how you assembled it.

Have a look at this from the inventor of the HDRI format and the author of the first HDR tool ever:
http://projects.ict.usc.edu/graphics/HDRShop/main-pages/intro.html

Notice that in the second and third sets of images the overall exposure is the same only some areas are blown out in the 8bpp image. Mixing the top 3 sets is tone mapping. See?
 
You're still confusing HDR with tone mapping though. If it's in JPEG format it's not HDR no matter how you assembled it.

Have a look at this from the inventor of the HDRI format and the author of the first HDR tool ever:
http://projects.ict.usc.edu/graphics/HDRShop/main-pages/intro.html

Notice that in the second and third sets of images the overall exposure is the same only some areas are blown out in the 8bpp image. Mixing the top 3 sets is tone mapping. See?

yes, i know that... im not confusing the two, im mearly stating what a HDR image should be comprised of in the shooting stages, not in the processing stage.
 
Interesting page — thanks :)

NP, There are more detailed properly presented pages from both Ward and Debevec from siggraph 97, 98, and 2001. That's just kind of a quicky read intro thingy. :D It's actually part of the HDRShop utility DL page. ;)


@Arch,
Ah, OK I see.
 

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