Small and seemingly insignificant events occur every second of every day in every place on earth, hidden and unknown beyond the direct particpants in the course of their daily lives. Dramas unfold at every level, from far above the atmosphere to the microscopic.

Please read on as I regale you of one such insignificant and inconsequential trek, through seldom walked scrub to a little known destination. Sometimes the pea-shooter over my shoulder reaps a rabbit for the following day’s meal but on this occasion my Lowepro back pack was shouldered, tripod attached while carrying camera, 70-200 Nikon glass with 1.4 teleconverter in between.

The Pohangina river flows from the Ruahine mountain range, coursing south along the foothills to Ashhurst township, where it meets the Manawatu river, the combined flow skirting the city of Palmerston North and onto the western coastline meeting the ocean at Foxton Beach, around 35 kilometres from Palmerston North.

An unfriendly tramp through dense unyielding undergrowth, littered with dead leaves, broken branches and heavy cover over uneven ground often giving way only to thickets of wild blackberry (the source of dark purple fruit stains still visible in my mouth on arrival back home during summer months) opens eventually to a small lagoon. Nestled at the base of the 300 or so foot high, steep river bank the stream feeding this micro swamp-land empties into the Pohangina river undercover of lush watercress canopied by Willow and Wattle.

The kilometre or so walk takes much longer than the usual 8-9 minutes of a brisk walk along the roadside over the same distance. Crossing the Pohangina river is the first obstacle, only about 250 yards down to where the small creek next to our house feeds into the river. The flow, though not usually quite to waist height at the creek entrance, is quite swift with slippery river rocks underfoot making for tentative crossings carrying several thousand dollars worth of camera gear!

The extraordinary amount of rain this season has kept the river levels high. Local council have had dozers and other earth moving equipment in the river bed moving river gravel from here to there but the river makes its own way – each flood yielding a different river scape at the will of the water or rather He who gives life and water.

Along the way there is opportunity to cut across farmland as I did on this occasion. The land owner, apart from milking cows, has several Boer Goats that roam and graze along the steep river banks. As seen in the distance here there is an addition to this red faced, white bodied goat family in the form of a half grown white youngster. Other goats are not far off enjoying the sunshine.

Further along a rabbit sits, watches and waits, deciding just how close to allow this outsider to approach before breaking to cover – only a few more paces beyond this shot actually – stopped at the tree line until I was in view again then disappeared into the shadowed undergrowth.

I followed the rabbit into the trees, soon to be ducking, pushing and even crawling through the entaglement. Progress being very noisey and disturbing to the locals (wild life) I made my way to a clearer area and just sat awhile allowing peace to settle again. Time to watch and listen and become more aware of my surroundings.

First noise of movement in the long grass was a Hare making exit, not going far slowly making through the dead leaf-fall.

The next visitor was the effervescent Fantail. Well, it was not really visiting me but more interested in the insects that were interested in me. A beautiful friendly little bird, not shy of people. I don’t think it is possible for a Fantail to remain still for more than half-a-second, left – right – spin around – spin back – up a branch – down a branch – out and do a figure 8 – back again!

This is one of a series of rapid fire exposures while the Fantail flitted above.

Before making for the lagoon at the small swamp a Tui swished into thick foliage and began preening. The New Zealand native Tui is not only distinct by its plumage, giving rise to the nickname of Parson Bird, but also movements and sound of flight. Each bird has its own particular flight sound and style. Sitting and listening to Tui song reveals the unbelievably many different sounds they make from bellbird-like chimes and chings to very soft and varied whistling, chirping and twittering – all beautiful melody. It seems to me that birds spend most of their day in song and worshipping their Creator.

After some preening the bird came closer into the open and actually bent over to check me out then decided to stay a while and continue with some self maintenance.

Now on my way again, the lagoon is about 60-70 yards through the thicket. Soft long grass makes progress quiet and pleasing. Ducks – Mallards, on the water. One is in view, others I can hear but they are obscured. Catching sight of me prompts a panicked scramble across the surface of the water and into the thick growth lining the banks.

Zoom in

Zoom in

Following the ducks to the north end of the water body, I set up the tripod behind foliage cover with a view over the water. Two Pukekos (swamp hens) are chirping way in the trees not far away. It is too early in the day for them to be roosting – the Pukeko often roosts in trees at night. Their chirping varies from their usual shrill scream to very soft and quiet sounds. It was ongoing.

Zoom in

A young Mallard Drake arrived with a splash voicing his arrival to no one in particular, sat for a while then slowly made for the willows overhanging the water. Two Mallard ducks soon joined the male. All the while the two Pukekos are fidgeting in the trees, up and down to the ground below and back up, chirping and squealing, not seemingly doing much else. After some time with only the Pukekos for company I moved position to the southern end of the lagoon, setting up some cover and some heaped grass for a pew and settled in behind the camera for another wait.

Patience … easy enough in the solitude of such a peaceful environ ambienced with bird-song. The two Pukekos continue to sound off, then a slowly approaching muffled fsssth-fsssth-fsssth comes to ear, across the water and low.

Zoom in

Zoom in

Scanning the shoreline for the source of the muffled sounds revealed movement in long grasses edging the water. Small black shapes emerged – chicks, fluffly jet black, red legs, white beaks, red around the base of their beaks and red ontop of their not-yet-feathered heads – baby Pukekos, beautiful!

The chicks made their way across the water’s edge and out of sight. Quickly grabbing my camera I selected a line of sight through the willows where hopefully the chicks would reappear. Another Fantail was working the cliff face opposite.

Small black furry shapes reappeared with the constant muffled fsssth-fssssth-fssssth and the two adult Pukekos gently chirping their young ones on.

One of the adult birds climbed the steep bank, patiently calling, coaxing and encouraging the young out of their hesitance, calling them to follow. I am privileged to have seen this small journey and wonder the all the never-seen interactions – the intricacy, the intimacy, the vastness and the beauty of creation.

The downside is the slightly visible disturbance to skies, water and smooth highlight areas of images. The effect is only slight and only the website presentation previews, the original files are not digitally fingerprinted and as such are clean, hi-res images.

Another misconception is that the HDR software requires images to have a large exposure offset range to effectively process the images into a single HDR. The reality is that the HDR software is equally as effective in subtle changes to images as it is for very high contrast images, even to toning down a few highlights by a small amount.

The two basic techniques for single image HDR are 1) to tone-map just the one original RAW image; and 2) to create a copy or copies of the original image and adjust the exposure up or down as required, then send these adjusted image(s) together with the original, for tone-mapping or fusion processing by the HDR software.

As previously mentioned some say this is cannot increase the dynamic range of an image. It has also been suggested that both the aforementioned processes produce the same result because they are both processing the same data. Really ??? …

The following image is a small valley a few minutes west of our home. The view is north-west just after sunset, so the light source is from the left in the image. The HDR effect is only subtle but I believe also improves the image.

Original image:

 
Exposure adjusted copy of the above image:

 
HDR result:

 
This is the HDR from using method 1) above, tonemapping just the one original image:

Notice the light distribution is different from the image copies HDR above and the sky detail is noticeably less.

The Dynamic Range of a camera image sensor can be described as the greatest possible amplitude between light and dark details the sensor can record.

HDR photography, while generally accepted as mulit-shot, or bracketed shot photography, is simply defined as technique(s) applied to create a single image with a wider tonal range than is possible with a single exposure.

It follows from the definitions above that a High Dynamic Range image is one that extends beyond the Dynamic Range of a given camera sensor, but all digital cameras are not created equal. It logically follows also therefore, that what is defined as an HDR image can also vary by camera/sensor and scene being photographed, and that by definition some cameras capture HDR, or higher dynamic range images by default relative to other digital cameras. Follow? No? Don’t agree? Read on …

For example, while my current Nikon D7000 has a Dynamic Range of 13.9 Ev (DxOMark Lab results), another similar common camera, the Canon EOS 7D, has a Dynamic Range of 11.7 Ev. Potentially for the Canon 7D to capture an image of the same scene with the same Dynamic Range as the Nikon D7000, it would require bracketed shots to make up the extra 2.2 f/stop dynamic range differential – in theory at least.

The extent of increasing the Dynamic Range of any image is only defined as an increase, not any specific amount. It may be subtle for some scenes or dramatic for high contrast scenes, each is HDR none the less.

In the same valley as before but facing home with the light source behind me, is the 0Ev exposure of a bracketed pair of images, below that is the second bracketed image offset by -2Ev:

 
-2Ev bracketed sequence image:

 
This is the above image in Lightroom, showing the histogram:

 
Now in lightroom I created a virtual copy of the first, lighter image and adjusted the exposure, black clipping and fill light as seen here the histogram is also almost a spot on match to the previoius bracketed image:

 
The Lightroom export process creates a new .tiff file applying the edited values, so the original pixel values are no longer available to the HDR software (or even Lightroom for that matter) in the newly created .tiff image.

Here is the result of tonemapping the one image:

 
Resulting HDR from the bracketed pair of images:

 
HDR from the lighter image plus the adjusted virtual copy:

The latter two are very similar and both are subtly different to the single image tonemapped result most noticeable in the sky details. HDR can be as delicate as it can be pronounced.

This image is very clean with little noise so the skies are all quite clean but where the differences are most notable is in the following images, the left side is a crop of the bracketed image HDR, and the right side image is a crop of the image copies (single image) HDR:

The foliage movement has created more ghosting and halo effects than the HDR software can effectively handle resulting in loss of fine detail, not only in the highlights but across the image generally.

The next pair of images are zoomed to 2-1, showing the foliage and the lack of resulting detail in the bracketed image HDR on the left, compared to the image copies (single image) HDR which once again is on the right. Foliage misalignment between the bracketed images has blurred the fine details as is shown, the single image HDR is sharper on the finer foliage:

 

 
A few more examples -

Patong Beach Ski Train original:

 
Exposure adjusted copy:

 
HDR result:

 
Nai Yang Crown Hotel Original:

 
Nai Yang Crown Hotel -2Ev exposure adjusted copy:

 
Nai Yang Crown Hotel +2Ev exposure adjusted copy:

 
Final single image HDR, original exposure and two exposure adjusted copies of the same image:

 
Original:

 
Exposure adjusted copy:

 
HDR from one image:

 
HDR from the original plus exposure adjusted copy:

 
Wanganui River original:

 
Exposure adjusted copy:

 
HDR from adjusted image copies:

 
HDR from one image processing:

 
Single image HDR processing, is it indeed false HDR – Faux? Or does it have merit, is it also valid HDR technique and true – Vrai? Well you have seen some results here so you can obviously make your own mind up on that one.

This, for me, is another effective tool at my disposal. There is no substitute for a quality exposure, as always the basic rule is GIGO, Garbage In Garbage Out. We can and do apply many different processing techniques to achieve the vision of that scene as we saw it at the time.
 
 

The society have regular meets and competitions, exhibitions and conferences, and publish an annual collective works photo book containing some of the outstanding images from members through out the previous year with some truly great images. I am looking forward to interacting and participating in the group.

HDR or HDRI – High Dynamic Range Imaging:

The blending of multiple exposures, with offset exposure values, of the same scene to create a single image with a wider tonal range than is possible with a single exposure.

The modern thinking is that HDR was initially pioneered and developed in recent years for use with digital images and computer-generated graphics. While techniques and technology have developed greatly in this age, the pioneering of high dynamic range images – using more than one exposure to increase the tonal range of a print – goes way-way back.

Jean-Baptiste Gustave Le Gray became famous for his seascape photographs 160 years ago. Le Gray used two negatives, one for the sky and a second longer exposure for the sea, to produce one positive print with a much higher luminosity, or dynamic range, than was possible with only one exposure – back in the 1850′s!

The technique further developed from the 1930′s into layering films of different exposure values to create the higher dynamic range, dogging and burning techniques were introduced to the process in the 1950′s. Now here in this digital age there is truly nothing new under the sun.

My personal preference for HDR images is realism, (not a fan of the overdone grunge look) where HDR technique is another tool at the photographer’s disposal. When executed carefully, HDR makes for some striking images – photos with the “wow” factor. In point of fact, HDR technique is more widely used by professional photographers than most people realise.

There are many software solutions now-a-days to aid in the combining of multiple exposures to create one HDR image. I use Photomatix Pro, which allows exporting the files directly from Lightroom 3.6 and reimporting the tone mapped combination image back into LR. I have tried the Photoshop CS5 merge to HDR, maybe I need to spend more time learning this particular tool, but not a fan at this stage.

The common HDR technique is to bracket two or three images with 2EV differential between each sequential exposure, then tone map these images in the software of choice. Of course the number of images and exposure offset value is subjective and will vary by photographer, equipment and scene. As an example, the images that follow of Mount Ruapehu on the Desert Road are unedited JPEG conversions of the original raw NEF files. The first image is camera exposure setting in Aperture Priority mode, the second image is -2EV from this setting while the third image is +2EV from the initial setting, each exposing for detail in a different area of the image:

These were exported into Photomatix Pro for tone mapping, then imported back into Lightroom 3.6 as a .TIFF format for final sharpening and colour adjustments. The resultant tone mapped image received a levels layer in CS5 to produce the final image, which worked very well in this case because the evening was still with no breeze and therefore no foliage movement:

This approach of layering several different images has obvious draw-backs for landscape photography. If there is a light breeze for example ghosting appears around leaves and grass and any moveable object due to the different position of the object(s) in each exposure, which is particularly nasty against a sky or a highlight area. There is also a chance of camera movement and misalignment between images. Bear in mind also, I am referring to a final image of quality to print to 24″+ wide (on quality print paper) where ghosting and fringing are all the more obvious, rather than a screen presentation image where a lesser quality image can still be made to look reasonably good.

When referring to image quality, a screen image of smaller proportions that looks “wow” what a great image may not be that great an image. Every image I publish, I know intimately. Scrutinize at 100% or even 200%, which is, or should be, standard practice I believe. Look for quality of detail, sharpness, fringing, moire, chromatic abberation, noise etc. You will often find the smaller screen image does not present that well under close examination, ergo printing to large sizes is out of the question.

Shooting RAW is also standard practice for me, allowing the maximum chance of maximum quality. Adjust the images before exporting to HDR software, eg. black clipping, white balance etc. Highlight recovery is ok for a small amount but it tends to leave a halo around leaves, branches etc that are against the high lit sky or background, which is accentuated more during the HDR process.

Another (and my preferred) Approach

If it is possible to balance an image exposure such that the camera histogram is not clipped or only slightly clipped, indicating that all the detail in the image is retrievable, there is the opportunity to create a finely detailed, noiseless HDR image from the one exposure.

There are a number of ways to create a second, exposure adjusted image from an original. I have found that exposure adjusted copies of the one image, saved in Capture NX 2 do not align perfectly when layered for HDR processing – not sure about the latest update though. Lightroom 3 can create a virtual copy of any image, which allows editing separately and apart from the originating image. Both the original image and the virtual copy can then be exported to Photomatix Pro for tone mapping, returning one HDR from the one image, and the layer alignment is always perfect.

Because both images are essentially the same image, detail is exactly the same for both images so when they are layered for tone mapping they are an exact match. Details remain crisp and noise is not introduced from the usual underexposed bracketed images used for HDR tone mapping.

In the following images of the Wanganui River, once again the first photo is a JPEG conversion of the original raw file with some black clipping applied. The second image is the exposure adjusted virtual copy of the original image by -2EV, and the final image is the returned tone mapped final HDR. The -2EV exposure adjusted image is much the same image that would be produced if I bracketed the shots. The important difference is that if this were a bracketed separate exposure, it would be very noisy in the dark areas which is the majority of the image, but because the image I am using is an exposure adjusted copy of a correctly exposed image there is very little or no noise and this obviously means finer detail in the resultant HDR.

The next example at Cape Turnagain of a wave splashing against a rock shows the subtle effectiveness of HDR technique between the first, original photo and the final HDR image:

A virtual copy of the above image, exposure adjusted by -2EV:

Both the original and virtual copies are exported from Lightroom to Photomatix Pro, to produce the following resultant HDR:

Finally a few more examples of (in my opinion) effective HDR both herein and elsewhere. Each image links back to the original: