# Probably stupid, Can you do this?



## Sirashley (Aug 12, 2008)

Okay, Just got into HDR. Here is my question. Can you make an HDR photo from a single exposure, then take that single RAW photo and save it three different times with different Ev (-2, 0, +2) settings? I did this and heres what I got. It seems to work, but my question is also, is there any reason not to do this? Quite honestly, it makes life really simple as I didn't have a tripod on this trip... Thanks in Advance...

Original photo








HDR Version


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## Syndac (Aug 12, 2008)

That's exactly how I do all my HDRs and as you've just showed, it works quite well.  I take all my pics in raw so that I can pick and choose which I want to create HDRs with.  It also allows you to do HDRs of motion.  Three seperate pictures wouldn't have worked in your example because of the movement from the cars and boats.


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## NikonNyc (Aug 12, 2008)

Great job man. I actually never thought of this! SO simple this is how i shall be doing my HDRs from here on in.


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## chrisburke (Aug 12, 2008)

this is how ive always done mine


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## prodigy2k7 (Aug 12, 2008)

Well you will probably get better IQ images if you actually take the correct exposed instead of doing it in photoshop making them brighter or darker...


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## SandShots (Aug 12, 2008)

what does hdr stand for?


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## prodigy2k7 (Aug 12, 2008)

high dynamic range


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## Alex_B (Aug 12, 2008)

i cannot see an hdr image here.

i only see a tonemapped image. the dynamic range is not increased though.

what you did is, you used more of your sensors sensitivity latitude that way, since there is more in your RAW data than in a single jpg. but still that latitude is very narrow.

this is not a scene made for HDR anyway, since the difference between bright and dark is small enough to be captured in one normal image.


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## Syndac (Aug 12, 2008)

prodigy2k7 said:


> Well you will probably get better IQ images if you actually take the correct exposed instead of doing it in photoshop making them brighter or darker...



Creating 3 exposures from a raw file isn't the same as using photoshop to brighten or darken an image.  Pretty much all of my best HDR images came from 1 raw file.


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## K_Pugh (Aug 12, 2008)

Yup i've got to agree. I've got the "detail" out of that one image with simple levels/curves/shadow&highlight (2 mins) - just except from the unnatural/oversaturated colours

I dare say using the method of creating 3 from 1 RAW may get you better overall quality (less noise) etc but i wouldn't call it a true HDR.


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## K_Pugh (Aug 12, 2008)

Sirashley, i hope you don't mind, it says your photos are ok to edit.. i just wanted to post this to demonstrate my point a little (i can take it down if you want, just say the word)






I can see the point of doing it though if you need to get the shadow detail up without bringing up too much noise - i'm sure bringing the exposure up in RAW adjustments is better than bringing the shadows up in photoshop.


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## AussieDee (Aug 12, 2008)

> then take that single RAW photo and save it *three different times with different Ev (-2, 0, +2) settings*? I did this and heres what I got.


I was rather curious as to how HDR was done and since a few people have done it this way, can I ask then... 

How do you combine the 3 separate images to one? How do you overlay them? Are you using Aperture or Photoshop? (I have both).


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## Syndac (Aug 12, 2008)

AussieDee said:


> I was rather curious as to how HDR was done and since a few people have done it this way, can I ask then...
> 
> How do you combine the 3 separate images to one? How do you overlay them? Are you using Aperture or Photoshop? (I have both).



I use Lightroom to create the 3 exposures from the RAW file, then Photomatix Pro to create the HDR from the 3 images.


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## AussieDee (Aug 12, 2008)

Are those programs, by chance, for Macs too? Or just for Windows?


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## ksmattfish (Aug 12, 2008)

K_Pugh said:


> ...using the method of creating 3 from 1 RAW may get you better overall quality (less noise) etc...



I'm not sure you would get a significant noise reduction.  As I understand it the reason noise is reduced when combining multiple exposures (made in-camera) is because the noise pattern is different in each exposure.  Three exposures made from the same raw file would all have the same noise pattern.  ?


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## K_Pugh (Aug 12, 2008)

You're probably right, in fact you will be. I just thought upping the exposure in RAW may handle it better than doing it afterwards in photoshop.. i have no idea though, it's not something i've done.


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## Sirashley (Aug 12, 2008)

Okay, it's time for the Pepsi challenge. I took a true HDR last week. Three separate exposures and made it into an HDR using Photomatix. Tonight, I took the middle photo from that set, opened the raw file, saved one at -2 one at 0 and one at +2. Then used photomatix to make a so-called HDR. The results were really really close. The true HDR has less noise and is perhaps a tad crisper when viewed at the full 10 meg size. The first one is true HDR, the last one is Fake HDR... Pay no attention to the subject...LOL... this was a test... But I think it shows that they are so close that the FAKE HDR is a very viable option when you don't have a tripod or you thought about HDR after the fact... Opinions?


True HDR








Fake HDR


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## Syndac (Aug 12, 2008)

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.


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## Sirashley (Aug 12, 2008)

Well others here were saying that is wasn't HDR... I thought it was, in order to show the difference between them I labeled it as fake. It just made it easier to distinguish the difference, sorry if I gave the wrong idea...


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## AussieDee (Aug 12, 2008)

I don't see a difference. I"m curious, tho, as to what the original looks like.


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## Sirashley (Aug 12, 2008)

Here is the original middle exposure


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## Syndac (Aug 12, 2008)

Here's an example of 3 exposures produced from one RAW file.  An HDR like this could never be produced by taking 3 pictures due to the movement:














And the resulting HDR:


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## Sirashley (Aug 12, 2008)

Oh yeah, Aussie, photomatix is available for Mac, that's what I did mine on... Photomatix is freakin awesome, super-easy, and really produces some amazing results...


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## AussieDee (Aug 12, 2008)

Sirashley said:


> Oh yeah, Aussie, photomatix is available for Mac, that's what I did mine on... Photomatix is freakin awesome, super-easy, and really produces some amazing results...



Thanks! I"m gonna go after it but....

I'm really new to all this HDR stuff - I'm impressed by the difference. 

The helicopter photo.... good example. So what adjustment is being made and by how much? And can it work with .jpgs from p&s's?  I don't have a dslr.   .... yet!


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## pasteofanchovie (Aug 12, 2008)

Thanks for posting this! I was wondering how to get started with doing HDRs.


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## Syndac (Aug 12, 2008)

AussieDee said:


> And can it work with .jpgs from p&s's?  I don't have a dslr.   .... yet!



If you're using jpgs you'd need to take at least 3 photographs at different exposures.  That's the advantage of using a raw file instead.


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## prodigy2k7 (Aug 12, 2008)

Syndac said:


> Creating 3 exposures from a raw file isn't the same as using photoshop to brighten or darken an image.  Pretty much all of my best HDR images came from 1 raw file.


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


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## prodigy2k7 (Aug 12, 2008)

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...


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## vbrandon91 (Aug 12, 2008)

syndac that photo looks awesome


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## AussieDee (Aug 13, 2008)

Syndac said:


> If you're using jpgs you'd need to take at least 3 photographs at different exposures.  That's the advantage of using a raw file instead.



Gotcha!  Thanks... I've got exposure settings on my p&s so I'm gonna give it a try.


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## Syndac (Aug 13, 2008)

prodigy2k7 said:


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



Not true.



prodigy2k7 said:


> 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.
> 
> ...



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.


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## Syndac (Aug 13, 2008)

AussieDee said:


> Gotcha!  Thanks... I've got exposure settings on my p&s so I'm gonna give it a try.



Keep in mind though that p&s cameras will generally create a lot more noise with HDRs.  Keep the ISO as low as your camera will go.


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## Syndac (Aug 13, 2008)

vbrandon91 said:


> syndac that photo looks awesome



Thanks.  I went down that rope 10 mins later. :stun:


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## nynfortoo (Aug 13, 2008)

Syndac said:


> 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.


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## vbrandon91 (Aug 13, 2008)

thanks for the info i think im actaully getting the hang of it now..

i got photomatix and ill run through some photos tomorrow


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## AussieDee (Aug 13, 2008)

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







And the HDR


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## nynfortoo (Aug 13, 2008)

AussieDee said:


> And the HDR




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.


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## Bifurcator (Aug 13, 2008)

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.  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  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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## K_Pugh (Aug 13, 2008)

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.


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## Arch (Aug 13, 2008)

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.


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## Battou (Aug 13, 2008)

Arch said:


> 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.


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## Bifurcator (Aug 13, 2008)

Arch said:


> 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.
> 
> ...



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?


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## nynfortoo (Aug 13, 2008)

Bifurcator said:


> 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



Interesting page  thanks


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## Arch (Aug 13, 2008)

Bifurcator said:


> 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
> ...



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.


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## Bifurcator (Aug 13, 2008)

nynfortoo said:


> Interesting page &#8212; 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.  It's actually part of the HDRShop utility DL page. 


@Arch,
Ah, OK I see.


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## nynfortoo (Aug 13, 2008)

Bifurcator said:


> 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.  It's actually part of the HDRShop utility DL page.



Yep, but it's a good example of the difference between lightening/darkening in post and straight from the camera with the correct exposure, in a round-about way, and so quite pertinent to the discussion  you can't rescue lost detail, basically.


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## Alex_B (Aug 13, 2008)

Bifurcator said:


> The "fake HRDIs" you guys are talking about are actually the results of a process called "Tone Mapping".



Thanks  so we finally arrived back at my post number 8  and have reached agreement


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## Syndac (Aug 13, 2008)

So how are my three chopper pictures above not "real" exposures?  The end result has a significant increase in shadow and highlight detail over the first.


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## Battou (Aug 13, 2008)

Syndac said:


> So how are my three chopper pictures above not "real" exposures?  The end result has a significant increase in shadow and highlight detail over the first.



As well as considerable aura and detail loss from the image information not actually being there and simulated or guessed by the processing software. Multiple exposures will get that information acurately where the processing software can not.

------------------------------------------------

Since everyone else is doing it below are a couple of my false HDR images done using the same process give or take, the difference is the information was there. These are one shot processed at five different exposure settings.


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## DATAstrm (Aug 13, 2008)

So my question is: Is there any way to do the tone mapping without adjusting the picture to 3 different "fake" exposures and using an HDR program?  IE, something that can directly do the tone mapping and produce the same or similar results from one file?

By doing this, it will not only prove that using one image is tone mapping, but also make it easier to produce the richer images in the future.  At the same time, the difference in a 1 file fake HDR and a 3 file real HDR could be demonstrated

-DATAstrm


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## Aggressor (Aug 13, 2008)

Hopefully this can clarify things by restating what K_Pugh already explained:

The easiest way to know if the image can benefit from HDR is by looking at the histogram.  If you look at the darkest shadows and they're completely black (ie. crawling up the left edge of the histogram) and if you look at the brightest highlights and they're completely white (ie. crawling up the right edge of the histogram), the image could use HDR.

The sections of the image that register on the far edges of the historgram are lost and are beyond the point of recovery.  The value of the section with the darkest shadow, if it is 0, will still be 0, even if the RAW is saved with EV -2 (it can't assume/interpolate a value less than 0 because it would have no idea what the original ratio is to its neighboring color in the original file); likewise, the value of the brightest highlight (assuming a 12-bit image), if it is 4096, will still be 4096, even if the RAW is saved with EV +2.  (I like to think of the computer having only 4096 fingers and toes -- it can't count higher than that)

By doing a 'true' HDR, by capturing, in the camera, a 'true' EV -2 exposure, everything that would have been <= 0 in the EV 0 image can now have a value to it.  The same would be similar for EV +2; values greater than 4096 can now be recorded.  By capturing values that would have been forever lost (always 0 or always 4096) in the camera, dynamic range is increased.

Tonemapping is a _part_ of creating an HDR because there needs to be a mechanism to blend the three exposures together.  The breadth of the dynamic range is _already_ determined by the time one gets to the tonemapping stage.

So... to answer your question, Syndac.  No, they are not 'real' exposures (it's a nice exposure, mind you).   With your technique, you have exploited the benefits of tonemapping, but in the true sense of HDR, your images did not expand the breadth of data collected by the sensor, so... well-tonemapped image, but not HDR.

Your technique is possible because, even though the sky may look blown out (which only a little bit seems to be in your image), especially in JPEG (range 0-255), the RAW file has a lot more lattitude (range 0-4095) in terms of storing the exact color.  Where the JPEG would render a point in the brightest sky as 255,255,255; the RAW may record it as 4090, 4090, 4090.  That's as good as white for a JPEG, but that may be the beginning of a silver lining of a cloud in RAW.


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## Bifurcator (Aug 13, 2008)

Syndac said:


> So how are my three chopper pictures above not "real" exposures?  The end result has a significant increase in shadow and highlight detail over the first.




"real exposures"???

I'll assume you mean real HDR Images as every photograph is a real exposure. 

And the answer is that technical terms apply. See above for the definitions of the terms being discussed (I guess post 8 and post 38) namely "Tone mapping", HDR or HDRI, RAW, and JPeg.  

But maybe this will help: What happens if you try to upload a RAW file to this website? You can't view it right? (unless you're on a mac but...) Same thing with an HDRI. The full width of HDR Images aren't displayable on most monitors at all and can't be viewed in a web browser. But you can save one exposure level of it as a jpeg which is viewable. You can also put it through a process called tone mapping before you save it as a jpeg. Tone mapping attempts to "mix" one or more exposure levels and then sandwiches then into a single viewable width (bit depth) that can then be saved as a non HDR image and uploaded here for display. But tone mapping is a process while HDR is a file format. The most popular extensions for HDRIs are .hdr and .exr So tone mapping is like sharpening or color balancing in that it's just a process. You don't need to tone map an HDR. In fact I guess 99% of HDR files are not tone mapped. They look just like a well exposed JPeg file when viewed on your monitor with HDR viewers. The difference being the exposure adjustment slider can mover farther to the right or left.

Additionally there are several ways to create an HDR file. Rendering applications can output them directly (maybe see www.lightwave3d.com among others). Some highly specialized camera equipment can create them on the fly in a single take. I guess such equipment costs about the same as a house.  And you can assemble them from multiple exposures from a regular camera like you and I have. Now here maybe is where your question gets answered. Since we dealing with different ranges or bit depths there will be little or no advantage in creating an HDR file from 3 identical (small range) exposures after just adjusting each one in Photoshop -which doesn't change the range - just the weighting. 

Your camera's image sensor is sensitive to a much larger range of light (light and dark) than it is able to capture in one picture. If you try to use just one picture to make the HDR then you're still limited to the range of that one picture. Your camera didn't expose for the brighter or darker areas. So you're just shifting the weight around within one range and using those shifted values to assemble something 4 times the width. 8 bpp --> 32 bpp. This isn't optimal and some say it'snot effectual at all but I haven't done the math so I dunno 1st hand. There's a much better more effectual way that's almost as easy and I always use it so I never bothered to figure out the lesser way. It would only be futile academics for me to. 

The better way is to take three or more (more is better - 12 to 15 is great if you can and if you have good enough software to do it) separate exposures thus utilizing the full sensitivity range of the image sensor in your camera. Now you're not simply shifting the same range of a single image but have multiple range*s* recorded and ready to assemble into the HDRI. All the highs and lows that would have been clipped in the single picture are captured and added in the various multiple exposures we took in the bracket. Assembling those into an HDRI is very effectual.

Did that make sense or did I just confuse you more?

The HDR file itself is not useful for web display and sharing purposes. For that we need to choose an exposure range we like and save it as something that is useful - like a JPeg file. Tone mapping or even sharpening for that matter, works better if we are working with a file that contains a larger range. So tone mapping an HDR file before saving it as a JPeg is "better" than tone mapping a file with less range. After you tone map it, sharpen it, whatever, then you save it as a JPeg and the newly saved .jpg file seises to be an HDRI.


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## K_Pugh (Aug 13, 2008)

No need to go that far. Here i've demonstrated the difference in doing 3 separate exposures 2 stops apart and doing 3 exposures from one RAW file.

1.





2.





I think that pretty much sums it up - you can't get back any lost detail. tonemapping has nothing to do with high dynamic range as such, tone-mapping can be fun to play with but it doesn't gain you any detail you never had.


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## Bifurcator (Aug 13, 2008)

Here you can see another similar technique called exposure blending. very similar to tone mapping but using multiple individual files without creating an HDRI first - it's also a slightly different process. In the same thread there are also tone mapped examples processed into JPeg files after assembling interim HDR files. 

http://thephotoforum.com/forum/showthread.php?t=127657


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## prodigy2k7 (Aug 13, 2008)

See I was right, go me! When I said photoshop I meant PP...


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## Syndac (Aug 13, 2008)

Aggressor, K_Pugh, Bifurcator, 

Thanks for the info.  I actually did my own little experiment right before K_Pugh's last post where I took a pic purposely underexposed by 4 stops in RAW format and attempted to recover it.  Yes, you are correct in that the data was lost.  I blame the many resources that have led me to believe otherwise while dealing with RAW files.  I have several magazines stating that the advatange of shooting RAW is that if your shot is over/under exposed, it can be corrected without any loss of data.  That's the point I was basing my argument on which as I've just discovered from my own experiment and K-Pugh's, is not true.

I'll still continue with my current method on any moving subjects though as it's the only way to capture it. (such as the previous chopper example)


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## rasheemo (Aug 13, 2008)

Alex, prodigy, battou, and nynfortoo are all correct.

YES, there are advantages to making an "HDR" out of one image, like when you won't be able to get the same composition due to movement or whatever, but that is not true HDR, and getting different exposures BEFORE uploading your pictures to your computer is ALWAYS better than forcing different exposures with one RAW.


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## vbrandon91 (Aug 13, 2008)

so how can i make a "fake" hdr?


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## Resin42 (Aug 13, 2008)

Syndac said:


> I have several magazines stating that the advatange of shooting RAW is that if your shot is over/under exposed, it can be corrected without any loss of data.  That's the point I was basing my argument on which as I've just discovered from my own experiment and K-Pugh's, is not true.



Yeah I've seen that kind of thing in a lot of magazines. I wouldn't go so far to say it's not true just a bit simplistic. PP exposure adjustment can recover detail from over and under exposed shots but not if they're too far gone in either direction. Blacks will stay black and whites will stay white. Photoshop can do a lot of things but it can't save an shot that was wrecked to begin with.


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## Sirashley (Aug 13, 2008)

Aggressor, your answer makes the most sense from a technical standpoint and I appreciate the post, Pugh, yours shows the actual difference... This was the answer to my original post, because I was wondering what the difference was between the way I did the image and the true way an HDR is done. So if anything, the way I was doing it was a good tone-mapping, and that's good to know that I can do that if I don't have a tripod to do an HDR exposure... Thanks for the detailed explanations everyone...


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## Battou (Aug 13, 2008)

Syndac said:


> I'll still continue with my current method on any moving subjects though as it's the only way to capture it. (such as the previous chopper example)



I wanted to imply that there is still a better way to do that. I have a couple processed at the moment, but those are all easily replicable at a stand still. I'll do one up with one or two of my heilo pics this weekend when I get the time, if I can find the originals.



vbrandon91 said:


> so how can i make a "fake" hdr?



Monkey with the exposure slider in Photoshop and merge to HDR. Seriously though, HDR and False HDR are way overused, it's not a toy and should be used wisely. It also should not be called HDR....but that's alredy been said 


Battou said:


> ...Since everyone else is doing it below are a couple of my false HDR images done using the same process give or take, the difference is the information was there. These are one shot processed at five different exposure settings.



Picture 1 (Note, final image was reprocessed after blue tinge was pointed out)

























Image 2


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## Syndac (Aug 18, 2008)

I know this thread died, but I just bought a magazine today (August 2008 Digital Magazine UK) which once again has a tutorial on making what they call an HDR from creating 6 exposures from 1 raw file, claiming it provides more information out of the standard range of an image.  It's magazines like this feeding me the info I've been posting about in this thread.


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## prodigy2k7 (Aug 18, 2008)

Syndac said:


> I know this thread died, but I just bought a magazine today (August 2008 Digital Magazine UK) which once again has a tutorial on making what they call an HDR from creating 6 exposures from 1 raw file, claiming it provides more information out of the standard range of an image.  It's magazines like this feeding me the info I've been posting about in this thread.



yes you get more data but you get even MORE data with 6 real exposured from the camera


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## Syndac (Aug 19, 2008)

prodigy2k7 said:


> yes you get more data...



So then technically it's still an HDR.


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## prodigy2k7 (Aug 19, 2008)

more data doesn't necessarily mean HIGH dynamic range...


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## Arch (Aug 19, 2008)

No, you don't get 'more data' as in the creation of more data than the original exposure.

What that magazine is trying to say is that it can _reveal_ more data, but thats all tone mapping is really doing (among other things) , revealing data which is already there. This can also be done in several other ways.

The only way of creating a 'true' HDRI, is to take multiple exposures, as only then are you adding dynamic range which isn't available from the sensor in one exposure.

As i have said before there is nothing wrong with either method if it suits the job you need it for. I sometimes target zones in an image and use layer masks with curve layers... i am still increasing the range of the image, so in a sense even this ends up as an image with a higher dynamic range.


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## Sirashley (Aug 19, 2008)

Ok, How's about EDR then, Enhanced Dynamic Range..., it's better than Fake HDR...LMAO...

I'm glad I started this thread because I have learned allot from reading the responses... Thanks guys... I stumbled across this for anyone with any other questions, I think this page really simplifies things for those just starting out

http://www.popphoto.com/howto/3038/how-to-create-high-dynamic-range-images.html


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## photo28 (Aug 19, 2008)

Can you make an HDR with Adobe Photoshop 7.0?


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## reg (Aug 19, 2008)

Syndac said:


> Creating 3 exposures from a raw file isn't the same as using photoshop to brighten or darken an image.



By definition, it is.


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## Syndac (Aug 19, 2008)

reg said:


> By definition, it is.



By "image" I'm refering to a jpg which contains less information than a RAW file and loses data per re-save, so no it's not the same.


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## Syndac (Aug 19, 2008)

Arch said:


> No, you don't get 'more data' as in the creation of more data than the original exposure.



Several people so far have said a raw file contains a couple stops more data than a jpg and I have quite a few magazine articles (HDR and RAW related) that seem to state the same thing.

I'm a photography magazine freak btw.


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## prodigy2k7 (Aug 19, 2008)

I disagree reg, althought I am a newb it doesnt sound right to me. Although Photoshop and other programs call it that, is it really adjusting the "Exposure". What is exposure by definition, I dont see how you can adjust it and call it 'Adjust the exposure' lets say...

Exposure to me is how much light is hitting the sensor isnt it? The Photoshop has some mathematical formula to produce similar effects, but is it really adjusting the exposure? Not IMHO.

On that note, multiple shots in camera will probably produce a better image with less noise (speculating). Also have a higher dynamic range, if you need be. In some situations your camera may have washed out skies and black shadows with no detail, photoshop probably/cant reproduce some blown out highlights and no detail shadows...

I will always use HDR in camera. Never in photoshop.


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## Aggressor (Aug 20, 2008)

Syndac said:


> Several people so far have said a raw file contains a couple stops more data than a jpg and I have quite a few magazine articles (HDR and RAW related) that seem to state the same thing.




Yes, it's true that RAW files contain more data than your traditional JPEG.  That is partly because of the higher bit-depth (12-bit in Nikon vs 8-bit JPEG).  Adding on to my previous explanation and further elaborating Arch's statement on revealing more data:

When saving files with shifted EV (+2 or -2), all it does is shift the center point of the values.  For example: for a RAW file with a center-point of 2048 at EV 0; a file saved as (EV -2), a pixel with a value of, say, 5 at EV 0, may now be 1024, and a pixel with a value of 3800 may now have a value of 4096 (blown out).  The values, of course, are approximate as (I don't believe) the values are filled in a linear fashion. 

So, in essence, all that is happening is that the differences are more pronounced when changing the EV in the file.  In the RAW file, the dynamic range is fixed as soon as it is saved.  By changing the center point of the RAW, deep highlights or bright highlights will be emphasized, allowing tonemapping to be easier.


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## Syndac (Aug 20, 2008)

I don't see how you can say that since it has data outside of the range of a jpg, it can't be considered to have higher dynamic range.  It may not be as much as taking multiple exposures but based on the definitions here it can still be called high dynamic range.  I'd consider straight tonemapping to be the process done to a single jpg.


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## Arch (Aug 20, 2008)

Syndac said:


> Several people so far have said a raw file contains a couple stops more data than a jpg and I have quite a few magazine articles (HDR and RAW related) that seem to state the same thing.
> 
> I'm a photography magazine freak btw.



Yes that is the advantage of shooting RAW (i do all the time), but this doesn't mean that extracting different versions of the same RAW _adds data_ to the dynamic range of the single exposure.
As i mentioned, i can extend the visable dynamic range of my RAWs by using curves layers, and if i like i can say the result has a higher dynamic range... but it isn't a true HDR (in its modern context). In the same way, an image created using software such as photomatix and one RAW file isn't true HDR either... however it can (and commonly is) called that.

I don't have a problem with people saying 'HDR' to a one RAW tonemapped image (i think in future the meaning will end up covering all tonemapped images)... but the term 'fake HDR' could also be used to discribe it... no biggie.


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## reg (Aug 20, 2008)

prodigy2k7 said:


> I disagree reg, althought I am a newb it doesnt sound right to me. Although Photoshop and other programs call it that, is it really adjusting the "Exposure". What is exposure by definition, I dont see how you can adjust it and call it 'Adjust the exposure' lets say...
> 
> Exposure to me is how much light is hitting the sensor isnt it? The Photoshop has some mathematical formula to produce similar effects, but is it really adjusting the exposure? Not IMHO.
> 
> ...



Uhhhhhhhhhhhhhh....

Guy said that "3 exposures *FROM A RAW FILE*" is not the same as using photoshop to "lighten or darken an image".... I said I disagree. He said that by image he means a jpg file. 

Kthxbai.


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## Syndac (Aug 20, 2008)

reg said:


> Uhhhhhhhhhhhhhh....
> 
> Guy said that "3 exposures *FROM A RAW FILE*" is not the same as using photoshop to "lighten or darken an image".... I said I disagree. He said that by image he means a jpg file.
> 
> Kthxbai.



Huh?  You're confused.  My original quote that you argued:


			
				Syndac said:
			
		

> Creating 3 exposures from a raw file isn't the same as using photoshop to brighten or darken an image.



How can you possibly claim that working with raw files is the same as working with a jpg in photoshop?  You make absolutely no sense.  If that were the case why would raw files exist?


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## prodigy2k7 (Aug 21, 2008)

Syndac said:


> I don't see how you can say that since it has data outside of the range of a jpg, it can't be considered to have higher dynamic range.  It may not be as much as taking multiple exposures but based on the definitions here it can still be called high dynamic range.  I'd consider straight tonemapping to be the process done to a single jpg.


Just because there is "more" data in a raw file, doesnt mean "more" is "high" in High Dynamic Range...

I guess $5 is a lot of money compared to $0.01, yes in comparison but we never say $5 is a lot of money because in general its not a lot of money.


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## Syndac (Aug 21, 2008)

prodigy2k7 said:


> Just because there is "more" data in a raw file, doesnt mean "more" is "high" in High Dynamic Range...
> 
> I guess $5 is a lot of money compared to $0.01, yes in comparison but we never say $5 is a lot of money because in general its not a lot of money.



But then it comes down to your definition of "high".  If it's agreed that it's high*er* dynamic range, then I should be allowed to call it an HDR since it has more dynamic range than a standard jpg. :mrgreen:


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