Taming the HDR Beast

HDR ..................................................................................Blending

HDR Blending
I have never been a big fan of heavily tone-mapped HDR images, but I appreciate that it is all a matter of taste. I frequently use various post processing techniques to expand the dynamic range of my pictures, but I draw my personal line somewhat short of "cartoonish", “painterly” processing. I want my viewers to see the image as I saw the scene and, at most, ask “Did you use HDR?” and not exclaim “WOW, you really used HDR”. When using HDR programs such as Photomatix or Photoshop’s HDR Pro, I often struggle to keep the effects under control and I find that a level of tone-mapping that works well in one part of the image may be over the top in another. Increasingly I have been using image blending to manage my HDR work. The techniques are simple and provide almost infinite control over the impact of HDR and tone-mapping. 



Enhancing the Depth
Last week I got out early to catch the effect of the morning fog on the

Westmoreland Fog

early spring colors. In Westmoreland, NH, I found a nice composition with the hay wagon sitting expectantly in a pasture and the classic red barn seen on the hill above. The arrangement provided a nice sense of depth with the fog having a much stronger softening influence on the distant barn. I liked the image but I felt the effect would be stronger if I could enhance the crispness of the wagon. Enter tone-mapping. 



Given the soft light, high contrast was not an issue, so I had no need for HDR techniques to capture the full dynamic range. I didn’t capture multiple bracketed images, but I could enhance tonal contrast by applying tone-mapping to a single image. In Photoshop, I processed the image to get the best result using my standard techniques. I didn’t want to punch up the colors and contrast too much and thereby loose the soft feel of the mist, but I felt that objects in the foreground, especially the hay wagon, could benefit from crisper detail. After I was happy with the base picture, I duplicated

Tone-Mapped Crazy

and flattened the image and then opened it in Photoshop’s Tone-mapping tool. A full discussion of the use of this tool is beyond the scope of this article and also pretty much beyond the scope of my expertise. Suffice it to say that my usual approach is to

play around with the sliders until I feel I have a good result or become frustrated and chuck the whole thing. Typically I end up with something that is dramatic but beyond what I would generally feel comfortable with as a reasonably natural representation of the scene. At this point, instead of giving up in despair, I often use image blending to mute the tone-mapping effect. 

Tome-Mpped Layer at 25% Opacity & Masked

 In this case, I copied the tone mapped layer to the top of the layer stack of the original. Proper alignment was not a problem given that the two layers were from the same image. I then was able to adjust the opacity of the overlying tone mapped layer to get just the amount of enhance contrast that I wanted in the foreground elements. This global adjustment resulted in excessive contrast in the distant background, especially the misty barn. By painting with black on the mask layer I was able completely remove the tone-mapping effect from areas of the background enhancing the sense of depth in the image. 

Blended Image

Blending together a tone-mapped and regular image allows full control of the amount and location of the enhanced effects. Various levels of HDR/Tone-Mapping can be painted in by applying different levels of gray to the layer mask. White reveals all, but middle gray shows only a partial effect and because all the work occurs on the mask you can adjust and modify as much as you want. In this picture I used a single Tone-Mapped image but a bracketed, multi-image HDR layer works just as well. 


Scott Farm Rainbow

Scott Farm Rainbow

In another example I worked on an image from a wedding at the Scott Farm in Dummerston, Vermont.  The union was blessed by a beautiful

Over the Top

rainbow.  I captured the color with the farm and a classic truck in the foreground, but I thought the truck was a bit dull and flat.  At home, I created a tone-mapped version.  I typically go a bit heavy with the toning, since I know it will be muted in post.  Again, I modified the effect with opacity and then use a mask to apply it only to the tuck.  I had a great time adjusting the opacity to find the right amount of enhancement and I still may mute it a bit further.

Tone-Mapped Truck

So get out there and HDR your brains out.  Not to worry, you can always calm the craziness with a little gentle blending.


Jeffrey Newcomer
Partridgebrookreflections.com