# HDR with one RAW?



## Trigger (Dec 30, 2012)

I read somewhere how one can make an HDR from one RAW file by increasing the exposure on one, decreasing on another, then combining the three for an HDR.  I just tried this (saving them all as JPGs as well as TIFs) and it wouldn't work.  Both the HDR Pro in PS and HDR Efex in NIK wouldn't do it.  What am I doing wrong or missing?


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## 480sparky (Dec 30, 2012)

You can't increase the dynamic range captured in one image.  If the range of the scene is within the range of the sensor's capabilities, there's no need to do HDR.  If the scene's dynamic range exceeds the sensor's capabilities, you can't magically pull details out of pure black shadows and/or blown-out highlights in a single image.


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## thetrue (Dec 30, 2012)

Thanks for that explanation sparky, I was wondering the same thing


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## Trigger (Dec 30, 2012)

Are you sure?  I think I read that this is possible numerous times (and hey, if it's on the internet it must be true right? - LOL).

Again, I opened the RAW file in PS Camera Raw, increased the exposure by 1, saved that file as a separate TIF (and JPG), then opened the RAW again, decreased the exposure by 1, saved it as a separate TIF (& JPG), and also saved the neutral RAW as a separate TIF (& JPG).

So those three files won't work as a foundation for creating an HDR?


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## thetrue (Dec 30, 2012)

Why not try changing the exposure more, like +/-3 or something more drastic?


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## 480sparky (Dec 30, 2012)

Trigger said:


> Are you sure?  I think I read that this is possible numerous times (and hey, if it's on the internet it must be true right? - LOL).
> 
> Again, I opened the RAW file in PS Camera Raw, increased the exposure by 1, saved that file as a separate TIF (and JPG), then opened the RAW again, decreased the exposure by 1, saved it as a separate TIF (& JPG), and also saved the neutral RAW as a separate TIF (& JPG).
> 
> So those three files won't work as a foundation for creating an HDR?



The result would certainly *look* like an HDR, especially if you pushed the process to the 'cartoon' level.  But if the data in the shadows or highlights _just isn't there_, adjusting the exposure slider in post is only going to create a sick gray.


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## Trigger (Dec 30, 2012)

I think I just figured it out.  In NIK HDR Efex, the 3 images open up with an alert that all of the exposures are the same, but if I manually adjust the values for over exposed and under exposed ones, then it works.


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## 480sparky (Dec 30, 2012)

Trigger said:


> I think I just figured it out.  In NIK HDR Efex, the 3 images open up with an alert that all of the exposures are the same, but if I manually adjust the values for over exposed and under exposed ones, then it works.



How about a screen shot of the histogram?


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## thetrue (Dec 30, 2012)

And the result is.....?


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## Trigger (Dec 30, 2012)

480sparky said:


> How about a screen shot of the histogram?




I know nothing about histograms, so I'm all ears.


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## Trigger (Dec 30, 2012)

thetrue said:


> And the result is.....?



It's tough to tell as this is such a crap image to begin with.  I may try another, and will report.


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## Trigger (Dec 30, 2012)

It appears to work, although I don't have any RAW files that would be a good acid-test for this.  Sparky may indeed be correct, but perhaps you guys might want to try it out; let us know.


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## christop (Dec 30, 2012)

You cannot display or print an HDR image directly without somehow decreasing its dynamic range. This basically means you have to "compress" the brightest highlights and darkest shadows so they can both be displayed or printed on a low-dynamic range medium such as a computer monitor or paper.

One method to decrease the dynamic range is to decrease the contrast of the whole image, which generally results in a flat image. Another popular method is tonemapping, which also decreases the contrast of the whole image but attempts to maintain _local_ contrast--that is, tones near each other maintain their relative brightnesses. Other methods attempt to mimic the way the eye sees tones in a scene, which often result in more natural images.

With only one raw image, you have only a low dynamic range, so it's not HDR. You can still tonemap it as if it were HDR using the technique you described, though.


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## 480sparky (Dec 30, 2012)

Trigger said:


> 480sparky said:
> 
> 
> > How about a screen shot of the histogram?
> ...




You haven't even reached the dynamic range of the sensor. No HDR is needed.  You just need to adjust the black and white points


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## Trigger (Dec 30, 2012)

Ahh, ok, thanks christop.


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## Trigger (Dec 30, 2012)

Sparky, that was the histogram of the finished product.  Did you mean that you wanted to see the histo of the RAW?


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## 480sparky (Dec 30, 2012)

Trigger said:


> Sparky, that was the histogram of the finished product.  Did you mean that you wanted to see the histo of the RAW?



That explains why it looks so flat... Lack of bright highlights.

Yes, I'd like to see the history of the original.


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## Trigger (Dec 30, 2012)




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## 480sparky (Dec 30, 2012)

That doesn't tell me it needs any "HDR treatment" at all.  Maybe some contrast & saturation adjustments, but that's it.


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## Trigger (Dec 30, 2012)

Ya, but after reading that an HDR is possible from one RAW shot, I wanted to try it out.  It was one of the things that pushed me over the edge to shoot RAW instead of JPG.  I don't mind though that it's not the same as a properly done HDR, I'll just abandon that method.

Thanks for the comments, feedback and insight.


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## thetrue (Dec 30, 2012)

Shoot RAW anyway. Adjustability and IQ as a whole is definitely a plus.


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## 480sparky (Dec 30, 2012)

Trigger said:


> Ya, but after reading that an HDR is possible from one RAW shot, I wanted to try it out.  It was one of the things that pushed me over the edge to shoot RAW instead of JPG.  I don't mind though that it's not the same as a properly done HDR, I'll just abandon that method.
> 
> Thanks for the comments, feedback and insight.



It's not a 'useless' method, so don't toss it out completely.  If it can be utilized to get the results you want, then by all means, use it.


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## Trigger (Dec 30, 2012)

> Shoot RAW anyway. Adjustability and IQ as a whole is definitely a plus.




A part of me still wonders if, due to the JPG capabilities of today&#8217;s mid to high-end cameras, _and_ the fact that a JPG is the ultimate destination anyway for viewing/sharing our images on the web/email and various displays, is shooting RAW really worth it?  Don&#8217;t those extra bit levels in a RAW file get tossed out the window anyway when converted to an 8 bit JPG, or is it still better than an out-of-camera JPG?  RAW and big TIFs are certainly better for larger prints, but&#8230;.hmmm.&#8230;what do you think?


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## thetrue (Dec 30, 2012)

Please refer to my thread in which I get ripped in half for asking: http://www.thephotoforum.com/forum/beyond-basics/306466-raw-really-worth.html


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## 480sparky (Dec 30, 2012)

Trigger said:


> > Shoot RAW anyway. Adjustability and IQ as a whole is definitely a plus.
> 
> 
> 
> ...



Yes.... editing removes a lot of data.  The difference is...... when you shoot raw, you have ALL the data to start with so you have a tremendous amount of latitude when editing.  When shooting JPEGs, you are trying to edit what technically is the 'finished product'.

A JPEG is kind of like a finished sculpture... you really can't do much more with it without your tinkering becoming obvious to the viewer.  A raw file is like having the original chunk of stone to work with.


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## Buckster (Dec 30, 2012)

480sparky said:


> Trigger said:
> 
> 
> > > Shoot RAW anyway. Adjustability and IQ as a whole is definitely a plus.
> ...


I like that analogy.


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## Trigger (Dec 30, 2012)

While we're at it, as I'm new to RAW editing:

- When shooting in RAW, is it still critical to select an appropriate WB setting in the camera?

- In one's computer RAW editor (see attached), is it perfectly ok to select whatever WB setting provides the desired result, or is it best practice to use the "As Shot" one and go from there?

- Is "Auto" WB generally to be avoided, or does it usually do a pretty good job?


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## 480sparky (Dec 30, 2012)

Unless I'm shooting under known & consistent lighting (such as with my monolights or in a venue where I've recorded the WB before), I usually just shoot AutoWB and make any minor corrections (if needed at all) in post.

As for which WB to select, choose whichever one gives you the results _you_ want.


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## Ysarex (Dec 30, 2012)

Buckster said:


> 480sparky said:
> 
> 
> > Trigger said:
> ...



Me too. Thanks Sparky.


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## The Barbarian (Dec 31, 2012)

A raw image should have about nine stops of exposure in it.   If you set the exposure at different levels, you'll see different details in different places, such as very dark or very bright areas.    Combining the three and tonemapping will give you what the purists will swear is not an HDR, but does everything an HDR does.  Assuming you've got no more than nine stops of difference.   Otherwise, the only way to get it all is two or more separate exposures.  

I was at a university library, and no tripod.   Given that I'd have to stitch the photo to get what I wanted, the only way to go was to shoot in RAW and then make several different Jpegs.  As mentioned above, you can't lose shooting RAW, since you can always discard what you don't need later; having that extra data makes it possible to do things you hadn't considered when you took the image.


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## Trigger (Dec 31, 2012)

This has reminded me of two more questions:

1)  My camera will shoot 3, 5, or 7 images in auto bracket.  Will I definitely get better results with the most (7), or is 5 or 3 sufficient?

2)  When shooting a bracketed image for HDR, is shooting in JPG mode as good as RAW?


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## CaboWabo (Dec 31, 2012)

Read here this is a good spot to start and learn from http://www.thephotoforum.com/forum/hdr-discussions/285190-beginners-guide-hdr.html then when you understand you can move to auto bracket when you know what the scene calls for learn to drive before you race is the motto


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## Trigger (Dec 31, 2012)

Thanks, will do.  Have you had a look at the HDR Pro in CS6?  Just wondering if it's been improved over CS5.

Also for NIK (which I have); is the HDR Efex Pro _*2*_ much improved?


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## 480sparky (Dec 31, 2012)

Trigger said:


> This has reminded me of two more questions:
> 
> 1)  My camera will shoot 3, 5, or 7 images in auto bracket.  Will I definitely get better results with the most (7), or is 5 or 3 sufficient?




I always let the scene itself determine how many shots I take.  Whether it's 2 or 12, the dynamic range of the scene is what's important.



Trigger said:


> 2)  When shooting a bracketed image for HDR, is shooting in JPG mode as good as RAW?



Depends on your software.  Some won't handle raw files, so you need to convert them.  But I always shoot raw to begin with, and do minimal editing that's batch edited to all the image.


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## Trigger (Dec 31, 2012)

480sparky said:


> I always let the scene itself determine how many shots I take.  Whether it's 2 or 12, the dynamic range of the scene is what's important.



So basically, the greater the dark & light differential, the more exposure steps are desired?


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## 480sparky (Dec 31, 2012)

Trigger said:


> 480sparky said:
> 
> 
> > I always let the scene itself determine how many shots I take.  Whether it's 2 or 12, the dynamic range of the scene is what's important.
> ...




That's my method.  If I meter 9 stops from the lightest to the darkest parts of the scene, I'll take 9 frames.  Maybe 11 if I have time.

If there's 12 stops across the scene, 12 (14 if I feel like it).


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## christop (Dec 31, 2012)

480sparky said:


> That's my method.  If I meter 9 stops from the lightest to the darkest parts of the scene, I'll take 9 frames.  Maybe 11 if I have time.
> 
> If there's 12 stops across the scene, 12 (14 if I feel like it).



12 frames?? I feel that's a little excessive. Decent cameras these days (even my 8-year-old Canon 10D) can produce relatively noise-free images in the top few stops at low ISO's (and I'd shoot HDR's only at the lowest ISO my camera supports anyway). Thus I don't see any point in separating exposures by less than 2 stops apart. So to capture a scene with a dynamic range of 12 stops, I'd take up to 6 frames. For a 9-stop scene, I'd take only 4 frames. If I didn't care about a little more noise in the shadows, I might even go without the bottom 1 or 2 frames (ie, the overexposed frames) since the dynamic range of the scene is captured by a few of the bottom frames anyway but with a little more noise.

But maybe that's just me.


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## Buckster (Dec 31, 2012)

Perhaps Sparky would be kind enough to show us examples of some of his 9, 11, 12 and 14 image HDRs.  Would be especially interesting to see the 14 images that make up that last one!


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## 480sparky (Dec 31, 2012)

Buckster said:


> Perhaps Sparky would be kind enough to show us examples of some of his 9, 11, 12 and 14 image HDRs.  Would be especially interesting to see the 14 images that make up that last one!



I've never built one with 14 frames.  I just TAKE that many.  I don't use all of them, I just prefer to have the frames if needed in post.  Better to have them and not need them than need them and not have them.

But here's a 9-frame.  0 EV:








HDR w/ 9 frames:


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## Buckster (Dec 31, 2012)

With a full 9 frames, I'm kind of surprised that the areas of sunlit rock and sidewalk still appear to be blown out, while the darkest areas still seem to be a bit blocked up.


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## christop (Dec 31, 2012)

I think the image with the blown out highlights and blocked up shadows is a single exposure. The combined HDR is below and doesn't have either of those problems.


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## Buckster (Dec 31, 2012)

christop said:


> I think the image with the blown out highlights and blocked up shadows is a single exposure. The combined HDR is below and doesn't have either of those problems.


Ah, yes!  Quite right.  For some reason, there was no second image in my browser when I posted my reply.


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## 480sparky (Dec 31, 2012)

Buckster said:


> christop said:
> 
> 
> > I think the image with the blown out highlights and blocked up shadows is a single exposure. The combined HDR is below and doesn't have either of those problems.
> ...



Partly my fault.  It took me a while to wade through my PB account to find the HDR.


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## CaboWabo (Jan 1, 2013)

So in hdr should there ever be a case where there is a shadow where you cannot see the detail ?


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## The Barbarian (Jan 1, 2013)

> So in hdr should there ever be a case where there is a shadow where you cannot see the detail ?



If that's what you want for the image.   HDR is a technique, not a standard to meet.


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## 480sparky (Jan 2, 2013)

The Barbarian said:


> If that's what you want for the image.   HDR is a technique, not a standard to meet.



Precisely. Do a forum search for "HDR Shootout". You'll see all sorts of different results _from the same original images_.


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