nomadlens

7. High Dynamic Range

The next section in this RAW converters comparison is to test the ability of each application to deal with high dynamic range images, where problems exist at both ends of the histogram, and thus the competing demands of both highlight and shadow recovery have to be balanced.

The phrase ‘high dynamic range’ is familiarly associated with the processing of bracketed images, where a series of images at different exposure settings are taken such that between them all or most of the details in the highlights and shadows are correctly exposed. These are then merged according to various different algorithms and processes to produce a single image. These images often suffer from two flaws, low or compressed contrast and haloing around dark objects against lighter backgrounds. These problems can also emerge when we try to extract as much information as possible from a single image.

When confronting a scene with too much dynamic range one should if possible bracket the images but this is not always possible, especially when objects are likely to move between shots. As a landscape photographer living on the coast I frequently encounter this problem in sunset shots, where I want to get some detail into the skies to fully capture the range of colours, but also want some foreground illumination. The middle of the scene will likely feature the sea, which is moving, which would make the processing of a bracketed sequence of shots challenging.

Having said all that the image I have chosen to assess is a single shot from a bracketed sequence. It has been selected because the rock in the centre will show up any issues with haloing in a much more obvious way than many of the other sunset shots I have taken. The photo is of Unshore Rock at Northcott Mouth, North Cornwall, and was taken with the E-M1 and 12-40mm at 12mm, ISO200, 1/60s, f/7.1 with an exposure compensation of +1/3eV.

We have seen from the previous sections that all the raw converters have fairly powerful tools for recovering highlights and shadows, and will be able to easily extract available details from both in an image like this. This is not what I am seeking to assess here; what I am looking at is finesse i.e. how pleasing and balanced an image is possible. Yet again, this is another very subjective assessment. Raising the shadows creates noise of course so some noise reduction and sharpening has been applied to the image too, but no colour adjustments have been made.

The RAW Conversions

[You can click on the images to bring up a larger version in a lightbox.]

Settings & Notes

Lightroom

Tonal (Basic) – Contrast: +5; Highlights: -100; Shadows: + 75; Whites: +13; Blacks: -3; Clarity: +15
Tonal (Curve) – Highlights: -30; Lights: +10; Darks: +15; Shadows: -5
Sharpening – Amount: 40; Radius: 0.8; Detail: 25; Masking: 30
Noise Reduction – Luminance: 15; Detail: 60; Contrast: 50; Color: 25; Detail: 50; Smoothness: 50
Notes – Lightroom can go further in lifting the shadows but about three quarters of the way is sufficient. Slight haloing around the rock is partially ameliorated by lifting the midtones with a curve. The detail in the highlights is clearly gone forever.

Aperture

Tonal (Exposure) – Exposure: -0.18; Recovery: 1.5; Black Point: -.0.1; Brightness: 0.1
Tonal (Enhance) – Contrast: 0.12; Definition: 0.34
Tonal (Highlights & Shadows) – Highlights: 100; Shadows: 87; Mid Contrast: 14
Tonal (Curves) – A very shallow inverted S curve with its central pivot at 75%
Noise Reduction – Radius: 0.8; Edge Detail: 1.8
Edge Sharpening – Intensity: 0.71; Edges: 0.5; Falloff: 0.69
Notes – Slight haloing, which was difficult to fix as it was generally quite difficult to adjust contrast in the sky without severely crushing the blacks. I expect others could do better.

Capture One Pro

Tonal (Exposure) – Exposure: -0.05; Contrast: 6; Brightness: 5
Tonal (High Dynamic Range) – Highlight: 85; Shadow: 65
Tonal (Clarity) – Algorithm: Punch; Clarity: 13; Structure: 12
Noise Reduction – Luminance: 10; Color: 100
Sharpening – Amount: 100; Radius: 0.8; Threshold: 1.0
Notes – Very powerful and pleasing highlight recovery in the sky but at the expense of some haloing on the rock. The shadows could have been lifted much further.

AfterShot Pro

Tonal – Blacks: 0.14; Exposure: 0.02; Highlights: 100; HR Range: 65; Fill Light: 1.40; Fill Range: 0.12; Contrast: 16; Local Contrast Strength: 70; Radius: 45
Noise Reduction – Raw Noise Removal: On; Perfectly Clear Noise Removal Strength: 20; Detail:10
Sharpening – Amount: 65; Sensitivity: 8
Notes – Keeping the fill range value low allows fairly targeted adjustment of the shoreline without raising the clouds and the local contrast feature keeps the rocks dark beneath the sun. Whilst Aftershot’s overall image quality, in terms of detail, remains disappointing, its tools work very well in this instance.

DXO Optics Pro

Tonal – Exposure Compensation: -1.33; Smart Lighting Intensity – 181; Contrast: 5; Microcontrast: 10
Tonal (Selective) – Highlights: -20; Midtones: 5; Shadows: 10; Blacks: 2
Noise Reduction – Luminance: 20; Chrominance: 100; Low Freq: 100
Sharpening – Lens Softness Global: 0.20; Details: 60; Bokeh: 50
Notes – Quite substantial adjustments to Exposure Compensation and Smart Lighting but a pleasing result emerges.

Irident Developer

Tonal (In) – Exposure: -0.50; Shadow Fine Tune: +100; Highlight Recovery: 100
Tonal (Adjustment) – Brightness Shadows: +20; Brightness Midtones: +30; Brightness Highlights: -31; Contrast: +30
Tonal (Curves) – LAB luminance curve adjustments
Noise Reduction – Adaptive Early Stage: 5; ChromaLogic: 2; ChromAdaptive: 5; Luminance: 10
Sharpening – Algorithm: Richardson Lucy Deconvolution; Radius 0.60; Iterations: 20
Noise Reduction – Adaptive Early Stage: 5; ChromaLogic: 2; ChromAdaptive: 5; Luminance: 5
Notes – Whilst Irident Developer struggled with extreme shadow recovery it manages better with this less demanding example.

Photo Ninja

Tonal – Illumination: 25; Exposure Offset; -1.02; Highlighs: -0.10; Black: 0.70; Contrast: 1; Detail: 9
Sharpening – Strength: 50; Radius: 0.8; Noise Masking: 100
Noise Reduction – Algorithm: Noise Ninja 4 Turbo; Luminance Smoothing: 5; Residual Noise & Detail: 70; Color Strength: 50; Defringe: 0
Notes – Photo Ninja has a unique feature when it comes to dealing with completely blown highlights. It is able to substitute a nearby colour for which it does have data. I have done this here. Whether or not you like the effect is a matter of personal taste.

RAW Photo Processor

Tonal – Exposure: -1.12; Compressed Exposure: 0.90; Contrast: 5; Brightness: 75; Highlights Recovery: 1.80
Topaz Denoise – Strength: 0.05; Shadow: 0.14; Highlight: 0.00; Red: -0.62; Blue: -0.59; Clean Color: 0.11; Black Level: 1.00; Recover Detail: 0.21; Reduce Blur: 0.15; Add Grain: 0.10
FocusMagic – 1 pixel
Notes – For some reason it was far easier to use the documented highlights recovery workflow on this image with fully blown highlights than the previous one where they were only partially blown.

Comments

In almost all the other sections of this RAW converters comparison one or two renditions have jumped out at me as being preferable and there has been some small element of objectivity as to why. In this comparison it really does come down to subjective preference. Any judgement as to quality is made more difficult because the colour variation is so large. My personal preferences are based on the overall impact and on a couple of specific areas of the image.

The first is the haloing around the rock. Two types of halo are present in various images. All the images suffer from a very bright halo right on the boundary that is just a pixel or two wide, but beyond that some have a glow that extends beyond this. AfterShot Pro, Irident Developer and RAW Photo Processor are probably the best in this regard, but this is largely because their renditions have the least contrast in the sky.

The second thing that I look at in these images is the highlights in the sky and the beam heading out to the left of them. The clear winner here for me is Capture One Pro, but Lightroom, DXO and RAW Photo Processor do a pretty good job too. Photo Ninja is a strange case; it has the unique ability to paste colour detail back into an area with totally blown highlights. I’m not sure I care for it in this image; it may work better for others. To be fair, it’s not compulsory, and I could have rendered the sky very similarly to Capture One Pro.

My winner for overall impact would be Capture One Pro. However, none of the RAW converters does a bad job with this image and those with flat colour renderings could easily be improved with further processing.

We’ve spent three sections now looking at different aspects of shadow and highlight recovery. In the next section of this RAW converters comparison we’ll look at a different type of tonality problem, and see how well the applications can create contrast in Low Dynamic Range images.