Project 11: High Density Range

Hmm, HDR! ‘Density’, not ‘dynamic’ though – and judging by the way the course materials describe the process, it is more comparable to the Dynamic Range Increase (DRI) process in Photomatix, rather than High Dynamic Range.

I have not come across the term ‘high density range’ before – maybe this is just something that I have missed, or maybe the terminology has changed in the past few years (since the course materials were produced?), now that techniques to increase the dynamic range are becoming more well known.

Up until about eight months ago, I was totally enthralled by the High Dynamic Range process. Yes, the images look unreal if the settings are not applied subtly, but in all honesty, that didn’t really bother me. Back in early 2009, I had a letter published in Amateur Photographer magazine about this very subject – I mentioned in the letter that perhaps I’d outgrow my love for highly processed HDR images one day, but at the time of writing, I was having fun creating lots of whacky images with it!

Now, though, I have indeed outgrown it – well, at least I’ve outgrown using HDR for HDR’s sake, if that makes sense. I use it occasionally now, but I much prefer the subtler images produced by DRI, and I don’t feel the need to process every image I take in Photomatix any longer. Instead of becoming the primary technique I use, it has just become one of many processes that I can draw on if I feel that it would enhance an image.

So – this project looks at combining images to increase the dynamic range. The ‘still life’ example provided on the CD was interesting – a good example of where a high contrast scene can benefit from subtle combining of different exposures. I decided that a church window would be an appropriate subject for me to try the technique described. I took three exposures at 2 stops apart. Here they are:

I then layered the images in Photoshop. Although I had used a tripod, I have learned from experience that this does not guarantee that the layers are absolutely in alignment – I therefore used the ‘Auto Align Layers’ command to ensure good alignment.

I set the darkest (underexposed) image as the background, the correctly exposed image as layer 1, and the overexposed image as layer 2. I actually judged the overexposed image to be the best in terms of the church interior – it appeared too dark in the other two shots – but the window itself was full of blown-out highlights. I therefore chose a soft-edged brush, set to 65 pixels and 100% opacity. I carefully erased the main glass areas, then with a smaller brush set to 25%, I worked around the edges of the glass and the frames. The small windows at the top were particularly overexposed, as were the surrounding frames, so I completely erased the top layer in this area, then used a low opacity eraser to reveal some of the darker background image.

Next, I lowered the eraser opacity to just 10%, and partially erased layer 1 around the faces of the figures. This revealed some of the finer details from the background image – unfortunately they cannot be seen clearly in the low-res version I have posted below.

Finally, I flattened the image and used a soft-edged  ‘clone’ stamp to remove the distracting details from around the frame. I have deliberately not changed the Levels, saturation or vibrance of the image, as I wanted to see what the ‘high density range’ technique could do without these other tools. Here is the final result:

I am quite pleased with it, although I still feel that the frames around the top windows are too light, and that my use of the low opacity eraser has made them look a bit patchy - this may be correctable using the 'burn' tool. Next time I try this technique, I may use feathered selections for areas such as this, rather than the eraser tool, as this may give a more consistent finish.