# Are 1-frame HDR's really 'good as HDR'.



## 480sparky (Sep 1, 2011)

It was mentioned in yet another thread that taking one frame and creating a -2 and a +2 EV to combine with the original 0 EV to create a 'good enough' HDR.

So I decided to put that claim to the test.  I scrounged my hard drive for a 'suitable' set of -2/0/+2 frames, and found this one:








So, I used _one_ of the the original NEFs to create a -2, 0 and +2 version and used those to make a 1-frame HDR.  This is what I ended up with:









Then I took the actual _three_ NEF frames that were exposed -2/0/+2 in camera on-site.  Using those 3 frames, I created this HDR:







These have not been edited at all.... this is how they came straight out of the HDR processing.  Obviously, both need some color correction, but that's not the issue here... it's whether a single frame can be adjusted in post to -2 and +2 exposures and create the same image as a 3-frame build.


All settings are the same for both builds, save for having to manually set the EVs for the 1-frame build.

You can view the full-size images by clicking here:

1-frame HDR.
3-frame HDR.

Keep in mind I'm working with the original raw files.  Working with JPGs alone may produce different results


Thoughts?  Comments?  Suggestions?

.


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## Bynx (Sep 1, 2011)

I think it depends on the range of light in the image as to whether a single shot will do. Your example here doesnt have extremely bright or dark areas so this limits the number of shots that might be needed. Try the same procedure but with the sun shining and dark shadows present, or maybe a shot of the living room with a lamp on and very bright light coming through the window.


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## analog.universe (Sep 1, 2011)

Perhaps someone can correct me if I'm wrong here, but if I understand the theory correctly, couldn't the same result be achieved by simply applying a more complex tone curve to the original RAW?  Normally when you HDR, you have different exposures because the camera can't fit all of the dynamic range of the scene into one.  So you take a few, and then the HDR software creates a file with more information in it than any of the originals had.  If you're just processing your raw into 3 different outputs, and then recombining it with HDR, you're not actually gaining additional information, you can't synthesize more data.  What you do get is a different output curve due to a difference in processing method.  However, since you have the same input data whether you've split the RAW into 3 exposures or not, you should in theory be able to reproduce the output of the HDR by only manipulating your raw converter, since it has just as much data as the HDR program did.  Yes? No?


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## robertandrewphoto (Sep 1, 2011)

While they both have a similar result, the true HDR shot is much better

The sky is better, the detail in the rocks at the bottom are better, the shadows in the building are exposed better, there is no haloing....and that is just what I can tell with a quick glance.

In my opinion, there is no replacement for a true HDR and I won't ever process a single shot to have an HDR effect and call it HDR....It should just be called FHDR


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## SlickSalmon (Sep 1, 2011)

That's a really interesting experiment.  Thanks for conducting it.


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## 480sparky (Sep 1, 2011)

Personally, I think using a single frame simply cannot create a *true* HDR.  One frame simply cannot record enough dynamic range _if the scene is outside the capability of the camera/sensor to record_.  If the dynamic range of a scene is 12 stops, I doubt you'll ever get a good image using one frame.  And the wider the range of the scene is, the results will become even worse.


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## cgipson1 (Sep 1, 2011)

This is from a single frame (0) that I ran though PS, and changed the brightness to -2 and +2......






so it does work (Photomatix seems to do it best).

Here is the original (O) that I shot....   Major difference.. and to the good of the photo...


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## 480sparky (Sep 1, 2011)

cgipson1 said:


> .....so it does work.......



It really just looks like you increased the brightness.

Now, try three in-camera -2/0/+2 frames so we can see the difference.  We really can't compare an apple to an orange when we only have one of them.


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## Josh66 (Sep 1, 2011)

480sparky said:


> Personally, I think using a single frame simply cannot create a *true* HDR.  One frame simply cannot record enough dynamic range _if the scene is outside the capability of the camera/sensor to record_.  If the dynamic range of a scene is 12 stops, I doubt you'll ever get a good image using one frame.  And the wider the range of the scene is, the results will become even worse.


I guess it depends on you definition of HDR, but I would tend to agree that one frame cannot produce a true HDR.  After all, if you can do it in one frame, how is that more dynamic range than a 'normal' picture?

One-frame HDR's are just 'special processing' to me - there isn't really anything about the dynamic range that is higher than normal...

I have not yet seen a 'one frame HDR' that couldn't have just as easily been done with some curves adjustments...


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## cgipson1 (Sep 1, 2011)

480sparky said:


> cgipson1 said:
> 
> 
> > .....so it does work.......
> ...



I will see if I can get some shot....  . As far as the pics above.. look at the red bricks to the left of the car outside of the shadow area. basically the same "brightness" on both of them...


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## 480sparky (Sep 1, 2011)

cgipson1 said:


> ........I will see if I can get some shot....  . As far as the pics above.. look at the red bricks to the left of the car outside of the shadow area. basically the same "brightness" on both of them...



Are you going to edit your post again if I tell you what they look like?

Yes, it's better, but *IS IT HDR*? I can do the same thing, even without creating -2/+2 frames and going through the entire HDR process. With 'true' HDR, the highlights on the car and in the clouds would not be washed out.


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## cgipson1 (Sep 1, 2011)

480sparky said:


> cgipson1 said:
> 
> 
> > ........I will see if I can get some shot....  . As far as the pics above.. look at the red bricks to the left of the car outside of the shadow area. basically the same "brightness" on both of them...
> ...



Sorry about changing pics.. but had put the wrong ones up.. didn't have the real "0" on that set... 

I did these the the very first day I had photomatix so they are a little rough...


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## manaheim (Sep 1, 2011)

Think of it this way...

The human eye can see something like "21-23 stops of dynamic range".  Cameras can see like 7-9.  

HDR is intended to give you as close to what the human eye can see as possible, so you want to get as close to 21-23 as you can.

A single RAW image gives you approximately 4 stops of leeway- 2 in each direction.

This takes you from 7-9 to 11-13... about 1/2 of the 21-23 we're looking for.

So, no, it's not as good, and no you can't use tonal curves to achieve the same thing... unless, as bynx said, it happens to be a very low dynamic range scene to begin with.


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## Josh66 (Sep 1, 2011)

Is a low dynamic range scene really in need of HDR processing anyway?

I don't do a lot of HDR's...  (I do employ it occasionally though.)  It seems to me that there are three types of HDR...

True HDR - truly high dynamic range.

Cartoon HDR - you know what I mean.

Faux HDR - HDR that is really just tone mapping or creative use of curves.



It's been a while, but this is one of the last HDR's I've done...  2 exposures (I felt that was all that was required):




IMG_6172_and_IMG_6177 by J E, on Flickr

Not perfect, I know.  It is an example of a photo that would not have been even remotely possible with one exposure though.

edit
These are the two frames that went into it:




IMG_6172 by J E, on Flickr




IMG_6177 by J E, on Flickr


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## cgipson1 (Sep 2, 2011)

480sparky said:


> Personally, I think using a single frame simply cannot create a *true* HDR.  One frame simply cannot record enough dynamic range _if the scene is outside the capability of the camera/sensor to record_.  If the dynamic range of a scene is 12 stops, I doubt you'll ever get a good image using one frame.  And the wider the range of the scene is, the results will become even worse.



I do agree with this totally, for true HDR. If the detail is not in the images you are working with.. you can't pull it out of the  under's / over's and put it into the photo.. it doesn't exist. As pointed out, our camera only "see" about 10 stops... for true HDR, you have to have photos that encompass a wider range  than that 10 stops... or it isn't really HDR. I will concede the photo I posted above is more like a brightness fusion, than true HDR.


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## Bynx (Sep 2, 2011)

Josh Im not sure exactly what Im looking at in your HDR example. The second shot is without the green light (fluorescent glow). The third shot is only the glow. Is one shot with something turned off and the other turned on? Or more like after shining a bright light on a fluorescent material and all lights turned out and your shot was exposed for the glow in the dark. As Im writing this its starting to make sense and this isnt HDR so much as just layering two shots of two exposures many fstops apart. Nothing has been done to address the shadowed area of the final combined shot.


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## Over Exposed (Sep 2, 2011)

480Sparky, did you use this one for a shootout one time? I feel like I remember this one from before. Would you mind sharing the files so we can have a crack at it? I'd like to look at them and pick one to do a single RAW without using an HDR algorithm.


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## 480sparky (Sep 2, 2011)

Over Exposed said:


> 480Sparky, did you use this one for a shootout one time? I feel like I remember this one from before. Would you mind sharing the files so we can have a crack at it? I'd like to look at them and pick one to do a single RAW without using an HDR algorithm.



I used a different view, but yes, the subject was in one of the Shootouts.

-2EV NEF
0EV NEF
+2EV NEF


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## boon4376 (Sep 2, 2011)

This is my 1 frame HDR example... Using Photoshop CS5 Merge to HDR Pro - I created different exposure jpegs from my original RAW file to use.

Original Shot






HDR Shot - Shows a little more detail everywhere, most noticeable in the sand and top cliff, however it lacks that vivid wow-factor that a true HDR composite of RAW image files would provide... Because a real HDR image would contain things that simply would not expose in the original frame... And thus the sand and top cliff shadow area have an artificial look... Killed a lot of the interesting contrasts as well.

.. But its the first time I've attempted such a thing so something could have gone wrong.


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## SlickSalmon (Sep 3, 2011)

I don't think the issue is whether 1-shot HDRs are as good as multiple-shot HDRs.  Clearly, multiple shots are needed anytime the scene has a wider dynamic range than about 12 EV.  The real question is whether 1-shot HDRs are better than single-shot JPEGs, particularly in situations where only one shot is possible. [I'd include in that comparison even single-shot RAWs straight-processed down to 8-bit.]

When the scene is happening quickly, or when the scene has action, multiple shots are frequently impossible.  The world rarely holds still for us to set up a tripod.  Yet, the highlights and the shadows of such scenes are often crushed by digital camera compression algorithms.  What we've been shown in the above examples is that taking the time to render RAW images into three JPEGs that can be tonemapped improves the quality of the image.  

The old criticism of this method is that 1-shot HDRs amplify shadow noise.  But, the examples posted by 480sparky demonstrate that modern noise suppression routines (even those simply built into Photomatix) alleviate this problem.  I'm very pleased and surprised by what we've been shown here.


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## boon4376 (Sep 3, 2011)

SlickSalmon said:


> The real question is whether 1-shot HDRs are better than single-shot JPEGs, particularly in situations where only one shot is possible.



Well the Jpeg engine in my K-r made an absolute mess out of the above cliff image. Luckily I hit the "save raw" button just after taking it which saved it.


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## onelove (Sep 4, 2011)

Hello...total noob here.

I am very new to digital photography. I was fairly serious with film and darkroom techniques about 35 years ago but haven't shot much since.

So far I have only just started playing with Photomatix and everything has been single shot, handheld and only saved as jpg, not raw. They were all taken long before I even heard of HDR.

Here is what I have come up with so far. I know there are some serious noise and clean up issues but I do not have any other post processing software yet. I am just trying to learn one thing at a time.

I welcome critiques, but please be tolerant...this is all from my first day.

Thanks





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## onelove (Sep 4, 2011)

A couple more...






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## Shoal (Sep 4, 2011)

onelove, I like them. Some of the sky seems to have noise issues, but I really like where you are going with these!

I am guilty of one-shot HDR. I have had some results that I am pleased with from this method.


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## bryandadams (Sep 4, 2011)

@OneLove: Not a bad start at all.

For the original post: It's case specific. There are certainly times when a one shot HDR will render a very nice image. There are also times where it will take more than three exposures to make the HDR render as desired. The most exposures I've used in a single HDR was eleven. In that case I could have used less, but merely one exposure would not render well and would have left deep shadows in the image. Granted there are times that a one shot HDR may be a better choice, such as shooting an object in motion or when there is simply less dynamic range in the frame.


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## Bynx (Sep 4, 2011)

onelove, I think your first aim should be to create a realistic image. Later when you can control the sliders the way you want then go for the painting look which you have here. If its painterly then there is no control over that. But realistic has only one look. So thats why I suggest to aim for that rather than the look you have achieved.  And I say this because you yourself have admitted to being a newbie to all this.


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## onelove (Sep 4, 2011)

Thanks! I am really having a lot of fun with this. Tomorrow I'll take the tripod out and get some multiples to see how that plays out. Maybe go out to the swamps.

I can see that I need a few more tools in my belt before I am ready for prime time. Good advice about working toward realistic.  I can see that would be a good discipline to learn how to gain control.  I used to be a darkroom "magician" but also studied basic studio lighting and darkroom at the university level. You need to master the rules before you can bend them.  Thanks.

I do have a few commercial possibilities for some of the more extreme stuff in the Caribbean tourist market. They like bright colors and the "painted" look.  Here are a couple that kind of surprised me. They were grab shot from a hotel window in Bangkok with a small pocket point and shoot. I will eventually work the sky a bit, but not too much. It was a stormy afternoon and looked close to that in person.  






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## Bynx (Sep 4, 2011)

Your skies show typical Highlight Smoothing errors. Halos around the buildings in the second shot and both skies have that dirty gray look instead of clouds with some texture. Try adjusting the highlight smoothing slider and see if that improves the sky. It might also help with the overall appearance of both images. Both show poor HDR processing skills. The buildings have blotches of gray, for example the bottom right corner of the second image as well as the building located to the right of dead center in the first image, above the trees and the brown roofed building. The gray blotches show tone mapping issues.
Personally I like the processing of your first 3 images posted. I prefer the painterly look to the photographic look. Just the sky problems to solve and everything is ok.


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