At Tarbat Ness

Posted on by

Continuing the third day of my holiday last November, having been to the Reelig Glen in the morning, with the weather still mostly inclement, I went for a nice long drive up to Tarbat Ness by Portmahomack. The lighthouse – the third-tallest in Scotland – was engineered by Robert Stevenson in 1830, a stripy shapely construction standing on cliffs above the Devonian old red sandstone shore, making a great classic scene to photograph.

And this is the more immersive view of what it’s like to be there:

[sphere 3047]

Landscape and Geology – an NC500 road-trip

Posted on by

Back last November I spent a very happy few days staying up North; the first day was spent in Glen Affric (sunrise, trees, water and light).

Photo Map

Photo Map – a long drive around Wester Ross

In the few years since I was last up there, there’s been a concerted push to market the road around the far north of Scotland as an “answer to Route 66” and thereby promote it as a tourist attraction.

The second day of my holiday saw lousy weather, completely overcast and foggy for much of the time. So I spent the day driving around Wester Ross wondering where the scenery had got to… trying not to think of it as the NC500 but actually enjoying several stops along the route that I’ve been to previously.

The first stop was the well-known view from a layby in Glen Dochart, above Kinlochewe to admire the sinuous road:

An obvious scene: the road wending through Glen Dochart toward Kinlochewe (not depicted: Kinlochewe, because of the mist).

Pity about the mist…

A little further along on the way through Kinlochewe are two mountains – Beinn Eighe to the left and Meallan Ghobhar and Coille na Dubh Chlaise to the right. We pulled off the A-road and Doglet had his breakfast more or less directly on the Loch Maree fault-line whilst admiring the quartzite rock strata.

There wasn’t much to be said for the views across Loch Maree, although the contrast of dull grey skies and warm autumnal orange and yellow colours was pleasant.

Some years ago, there was a TV documentary, a former politician’s search for the most natural woodland in the UK. After much searching around down south in the New Forest, he came north and explored Caledonian Forest remnants, finally finishing up on an island in Loch Maree – a rather bizarre arrangement of an island with a lochan with another island inside that – on which he stated the trees were least likely to have been touched by mankind. There is an obvious viewpoint, a small section of beach, at Slattadale toward the north-west end of Loch Maree, from which the group of islands can be seen.

Of all the photos I made during that day, this was perhaps the most classical landscape, in that I had the idea for these photos – the location, leading lines of foreground boulders, large expanse of silvery water and Slioch in the distance – planned in my mind for ages before revisiting the area.

What you don’t see is how, while I was making these photos (long exposures, totalling a minute’s exposure, focus-stacked) there was another photographer sitting 20yd away, cooking his morning breakfast – so the photos fail to include the clouds of fragrant bacon and fish smoke billowing past the camera…

Speaking of lunch, mine happened at Badachro, at the Inn. Highly recommended – everyone loved Doglet, which is a good start, and the burger was tasty as ever. Mostly the thing I like most is how the coastline is just like Plockton – west-coast rocky sea-lochs and seaweed – but without actually being Plockton that everyone else flocks to see.

And this is what it’s really like at Badachro:
[sphere 2974]

On a previous trip I had explored as far as Poolewe but not had a chance to go further; this time I stopped off at Loch Tollaidh to admire the rocky outcrops across the water (Lewisian Gneiss and other igneous rock).

Classic Wester Ross landscape – huge lumps of Lewisian gneiss, beside Loch Tullie

Signs of industry: on the shore of Loch Tollaidh is a small jetty, presumably a put-in for boats to go inspect the small salmon farm. That and the remains of a very dead boat, wood bleached inland, caught my attention:

On travelling up the coast to Mellon Udrigle (what a wonderful name!) I was struck by the view across the Wester Ross Marine Protected Area to the mountains on the horizon on the mainland. On the left, a bit of misty cloud drapes over the top of Beinn Ghobhlach; to the right, there’s more mist flowing over Sail Mhor but the huge bulk of An Teallach was completely hidden behind the cloud.

A wide-angle panorama: low-lying cloud (with a bit of precipitation) and mist flowing over Sail Mhor – the full bulk of An Teallach is completely hidden in the cloud beyond.
The mountain on the far left is Beinn Ghobhlach.

By the time I got back onto main roads, with a very long drive ahead, the light was fading fast toward dusk and the blue hour and clouds in front were thick and closing in fast, so I made one final photo for the day by the side of Little Loch Broom and scarpered fast.

Lots of mist in the distance, travelling the A832 past Beinn Ghobhlach.
I was rather glad to get back in the car and head off before the weather got really bad!

Pentax K-1: an open-source photo-processing workflow

Posted on by

There is a trope that photography involves taking a single RAW image, hunching over the desktop poking sliders in Lightroom, and publishing one JPEG; if you want less noise you buy noise-reduction software; if you want larger images, you buy upscaling software. It’s not the way I work.

I prefer to make the most of the scene, capturing lots of real-world photons as a form of future-proofing. Hence I was pleased to be able to fulfil a print order last year that involved making a 34″-wide print from an image captured on an ancient Lumix GH2 many years ago. Accordingly, I’ve been blending multiple source images per output, simply varying one or two dimensions: simple stacking, stacking with sub-pixel super-resolution, HDR, panoramas and occasionally focus-stacking as the situation demands.

I do have a favoured approach, which is to compose the scene as closely as possible to the desired image, then shoot hand-held with HDR bracketing; this combines greater dynamic range, some noise-reduction and scope for super-resolution (upscaling).

I have also almost perfected a purely open-source workflow on Linux with scope for lots of automation – the only areas of manual intervention were setting the initial RAW conversion profile in RawTherapee and the collation of images into groups in order to run blending in batch.

After a while, inevitably, it was simply becoming too computationally intensive to be upscaling and blending images in post, so I bought an Olympus Pen-F with a view to using its high-resolution mode, pushing the sub-pixel realignment into hardware. That worked, and I could enjoy two custom setting presets (one for HDR and allowing walk-around shooting with upscaling, one for hi-res mode on a tripod), albeit with some limitations – no more than 8s base exposure (hence exposure times being quoted as “8x8s”), no smaller than f/8, no greater than ISO 1600. For landscape, this is not always ideal – what if 64s long exposure doesn’t give adequate cloud blur, or falls between one’s ND64 little- and ND1000 big-stopper filters? What if the focal length and subject distance require f/10 for DoF?

All that changed when I swapped all the Olympus gear for a Pentax K-1 a couple of weekends ago. Full-frame with beautiful tonality – smooth gradation and no noise. A quick test in the shop and I could enable both HDR and pixel-shift mode and save RAW files (.PEF or .DNG) and in the case of pixel-shift mode, was limited to 30s rather than 8s – no worse than regular manual mode before switching to bulb timing. And 36 megapixels for both single and multi-shot modes. Done deal.

One problem: I spent the first evening collecting data, er, taking photos at a well-known landscape scene, came home with a mixture of RAW files, some of which were 40-odd MB, some 130-odd MB; so obviously multiple frames’ data was being stored. However, using RawTherapee to open the images – either PEF or DNG – it didn’t seem like the exposures were as long as I expected from the JPEGs.

A lot of reviews of the K-1 concentrate on pixel-shift mode, saying how it has options to correct subject-motion or not, etc, and agonizing over how which commercial RAW-converter handles the motion. What they do not make clear is that the K-1 only performs any blend when outputting JPEGs, which is also used as the preview image embedded in the RAW file; the DNG or PEF files are simply concatenations of sub-frames with no processing applied in-camera.

On a simple test using pixel-shift mode with the camera pointing at the floor for the first two frames and to the ceiling for the latter two, it quickly becomes apparent that RawTherapee is only reading the first frame within a PEF or DNG file and ignoring the rest.

Disaster? End of the world? I think not.

If you use dcraw to probe the source files, you see things like:

zsh, rhyolite 12:43AM 20170204/ % dcraw -i -v IMGP0020.PEF

Filename: IMGP0020.PEF
Timestamp: Sat Feb  4 12:32:52 2017
Camera: Pentax K-1
ISO speed: 100
Shutter: 30.0 sec
Aperture: f/7.1
Focal length: 31.0 mm
Embedded ICC profile: no
Number of raw images: 4
Thumb size:  7360 x 4912
Full size:   7392 x 4950
Image size:  7392 x 4950
Output size: 7392 x 4950
Raw colors: 3
Filter pattern: RG/GB
Daylight multipliers: 1.000000 1.000000 1.000000
Camera multipliers: 18368.000000 8192.000000 12512.000000 8192.000000

On further inspection, both PEF and DNG formats are capable of storing multiple sub-frames.

After a bit of investigation, I came up with an optimal set of parameters to dcraw with which to extract all four images with predictable filenames, making the most of the image quality available:

dcraw -w +M -H 0 -o /usr/share/argyllcms/ref/ProPhotoLin.icm -p "/usr/share/rawtherapee/iccprofiles/input/Pentax K200D.icc" -j -W -s all -6 -T -q 2 -4 "$filename"

Explanation:

  • -w = use camera white-balance
  • +M = use the embedded colour matrix if possible
  • -H 0 = leave the highlights clipped, no rebuilding or blending
    (if I want to handle highlights, I’ll shoot HDR at the scene)
  • -o = use ProPhotoRGB-linear output profile
  • -p = use RawTherapee’s nearest input profile for the sensor (in this case, the K200D)
  • -j = don’t stretch or rotate pixels
  • -W = don’t automatically brighten the image
  • -s all = output all sub-frames
  • -6 = 16-bit output
  • -T = TIFF instead of PPM
  • -q 2 = use the PPG demosaicing algorithm
    (I compared all 4 options and this gave the biggest JPEG = hardest to compress = most image data)
  • -4 = Lienar 16-bit

At this point, I could hook in to the workflow I was using previously, but instead of worrying how to regroup multiple RAWs into one output, the camera has done that already and all we need do is retain the base filename whilst blending.

After a few hours’ hacking, I came up with this little zsh shell function that completely automates the RAW conversion process:

pic.2.raw () {
        for i in *.PEF *.DNG
        do
                echo "Converting $i"
                base="$i:r" 
                dcraw -w +M -H 0 -o /usr/share/argyllcms/ref/ProPhotoLin.icm -p "/usr/share/rawtherapee/iccprofiles/input/Pentax K200D.icc" -j -W -s all -6 -T -q 2 -4 "$i"
                mkdir -p converted
                exiftool -overwrite_original_in_place -tagsfromfile "$i" ${base}.tiff
                exiftool -overwrite_original_in_place -tagsfromfile "$i" ${base}_0.tiff
                mv ${base}.tiff converted 2> /dev/null
                mkdir -p coll-$base coll-$base-large
                echo "Upscaling"
                for f in ${base}_*.tiff
                do
                        convert -scale "133%" -sharpen 1.25x0.75 $f coll-${base}-large/${f:r}-large.tiff
                        exiftool -overwrite_original_in_place -tagsfromfile "$i" coll-${base}-large/${f:r}-large.tiff
                done
                mv ${base}_*tiff coll-$base 2> /dev/null
        done
        echo "Blending each directory"
        for i in coll-*
        do
          (cd $i && align_image_stack -a "temp_$i_" *.tif? && enfuse -o "fused_$i.tiff" temp_$base_*.tif \
           -d 16 \
           --saturation-weight=0.1 --entropy-weight=1 \
           --contrast-weight=0.1 --exposure-weight=1)
        done
        echo "Preparing processed versions"
        mkdir processed
        (
                cd processed && ln -s ../coll*/f*f . && ln -s ../converted/*f .
        )
        echo "All done"
}

Here’s how the results are organized:

  • we start from a directory with source PEF and/or DNG RAW files in it
  • for each RAW file found, we take the filename stem and call it $base
  • each RAW is converted into two directories, coll-$base/ consisting of the TIFF files and fused_$base.tiff, the results of aligning and enfuse-ing
  • for each coll-$base there is a corresponding coll-$base-large/ with all the TIFF images upscaled 1.33 (linear) times before align+enfusing
    This gives the perfect blend of super-resolution and HDR when shooting hand-held
    The sharpening coefficients given to ImageMagick’s convert(1) command have been chosen from a grid comparison; again the JPEG conversion is one of the largest showing greatest image detail.
  • In the case of RAW files only containing one frame, it is moved into converted/ instead for identification
  • All the processed outptus (single and fused) are collated into a ./processed/ subdirectory
  • EXIF data is explicitly maintained at all times.

The result is a directory of processed results with all the RAW conversion performed using consistent parameters (in particular, white-balance and exposure come entirely from the camera only) so, apart from correcting for lens aberrations, anything else is an artistic decision not a technical one. Point darktable at the processed/ directory and off you go.

All worries about how well “the camera” or “the RAW converter” handle motion in the subject in pixel-shift mode are irrelevant when you take explicit control over it yourself using enfuse.

Happy Conclusion: whether I’m shooting single frames in a social setting, or walking around doing hand-held HDR, or taking my time to use a tripod out in the landscape (each situation being a user preset on the camera), the same one command suffices to produce optimal RAW conversions.

 

digiKam showing a directory of K-1 RAW files ready to be converted

One of the intermediate directories, showing 1.33x upscaling and HDR blending

Results of converting all RAW files – now just add art!

The results of running darktable on all the processed TIFFs – custom profiles applied, some images converted to black+white, etc

One image was particularly outstanding so has been processed through LuminanceHDR and the Gimp as well

Meall Odhar from the Brackland Glen, Callander

Around the Black Mount

Posted on by

Detail of blades of grass poking throuhg a frozen Lochan na h’Achlaise, Rannoch Moor.

At the end of November I spent a happy Saturday afternoon driving out to the Black Mount area in Rannoch Moor, with photos in mind.

Didn’t help that I left the main camera battery at home in the charger, so was limited to the spare. Well, it makes one think when even turning the camera on to compose through the EVF uses finite battery life, especially in the cold. Lots of “pre-visualising” going on to keep the film-throwback photographer purists happy.

There were plenty of cars zooming along the A82 but a little stroll out into the bogs resulted in some nice landscape.

The crowning joy of the photographic excursion, however, was the total cliche scene of the Buachaille from the River Coupall. It’s sufficiently well-known that folks groan when it appears in photo-club competitions. The composition is more or less fixed, with varying extremity of weather conditions providing the value-additions to the photo.

This time, I spotted a little wisp of mist coming up Glencoe as I turned off down Glen Etive. There were only two other folks at the location; they said it was their second attempt that day as, on the way down the glen, there had been 20-30 folk milling around.

Funny how such an iconic landscape location still has people who will shoot it in suboptimal light.

We took a few photos, and dusk fell, with glorious shades of warm purple tints and an orange sky.

My temporary companions departed, leaving just me – well into post-sunset dusk blue-hour – at which point the wisp of mist rounded the base of the mountain underlining it in white to match the waterfalls in the river. And that is the shot of the day.

Buachaille Etive Mor from the River Coupall, Glen Etive

Stob Dearg – Buachaille Etive Mor from the River Coupall, Glen Etive

Hogmanay 2016/2017

Posted on by

Happy new year! I saw the year in from Blackford Hill looking at the fireworks over Edinburgh Castle.

Watching folks arrive was almost like a scene from Lord of the Rings – this line of torch lights processing along the hillside track, reminiscent of the last march of the Elves.

Loch Lomond: At Inversnaid

Posted on by

There’s a couple of picturesque views to be had just below the hotel at Inversnaid harbour – the waterfall cascading down amongst the rocks one way, and opposite, a line of boulders leading toward the Arrochar Alps across Loch Lomond. Can’t complain.

I don’t often use the Pattanaik algorithm in LuminanceHDR, especially for colour results, but it seemed to work really well with the waterfall, nicely balancing low-key levels and saturation.

Olympus Pen-F: first excursion photos

Posted on by

I’ve not wasted time before getting out and about with the new camera. I saw a photo on flickr of the sea stack at Muchalls on the Aberdeenshire coast, near Stonehaven, which prompted a visit to explore the area and drive through lots of scenery. Unfortunately the path down to the beach was too slippy and muddy, so I settled for a higher vantage-point overlooking the rocky beach.

This was taken using an Olympus 12-60mm f/2.8-f/4 four-thirds lens with adapter, circular polariser, ND4 and grad-ND4 filters.

Rocky coastline and small sea-stacks at Muchalls, Aberdeenshire

Rocky coastline and small sea-stacks at Muchalls, Aberdeenshire

I continued to drive all around the A93 loop from near Stonehaven to Banchory and Ballater – the road lined with favourable Scots pine trees. The sun set as I was passing the Muir of Dinnet. This sunset silhouette was made using my old Pentacon 50mm f/1.8 lens:

The real delight of the day’s drive was rattling down Glenshee in the dusk. It was -2C outside; with the light having faded, the sky was a beautiful shade of cobalt blue, against which the silvery white of the pure snow capping the mountains was simply breathtaking.

Sirius Rising over Leacann Dubh and Creag Leacach – I know it was Sirius because by the end of the combined 64-second exposure, Orion was well visible to its right.

It feels so good to be back enjoying the landscape again.

Ordinary Landscape

Posted on by

The other day, we had a proponent of “creative landscape photography” presenting at the photographic society. His results were outstanding. I even approved of some of his philosophy, which is saying something.

But … some of his decisions in the execution of that philosophy seemed off.

It’s great to hear someone ignoring the maxim “get it right in camera”, espousing instead the idea of “getting good data at the scene” and affirming the role of post-processing to polish the result instead. I believe strongly in the very same thing myself.

It seems strange that such a philosophy would lead to rejoicing in a camera’s dynamic range – no matter claiming to have recovered 4 stops from the shadows, it would still have been done better by HDR at the scene – where the data comes from photons working in the hardware’s optimum performance zone.

It seems strange that one would criticize such a camera for “not seeing the same way we do”, and go on to say that we need to enhance the impression of depth by using lower contrast in the distance.
The sensor’s response curve is smooth; it will accurately reflect the relative contrast in areas by distance. The only way it would not is if one’s processing were to actively include tonemapping with localized contrast equalization. Left to its own devices, the result will accurately reflect what it was like to be there – one of the greater compliments a landscape photographer could receive.

The problem is not with the landscape; it’s with the way that photography should aspire to relate to the landscape. “Creative” seems to be a euphemism for multiplying and enhancing every aspect, be it strong foreground (make it a yet stronger perspective with a tilt lens), contrasty light (more contrast slider), colour (still more saturation and vibrace to breaking point) and so on. The results create impact but without story or message; visual salt without an underpinning of a particular taste.

Of course we know that “realism” is a phantom. It’s true that no camera will capture quite the same as anyone sees. However, let me introduce a new word: believability, precisely the quality that one could have been there at the same time. That seems like a valid goal.

Have some believable landscape images – they mean a little to me; that suffices.

Hunting Kelpies

Posted on by

Situated right beside the M9, the Kelpies are a bit of a tourist trap, but it had to be done…

Rather stupidly, I set out with intentions of making long exposure photos of the kelpies – and then found after a few miles down the road that I’d left all my filters in the other camera bag. So, f/22 was deployed, along with a lot of stacking for synthetic long exposures. In one case it took over 60 images median-blended to eliminate the humans milling around. Still, it’s probably better that way – I’m always happier when image data arises from photons than algorithms or localized manipulation.

And some of my favourite shots are from the boardwalk through the marshes on the way back to the carpark.

The remotest glen?

Posted on by

Late November, very late autumn – short days of chilly weather and cold light – I set off for a drive through Glen Lyon. I’d not been there for at least five years; felt like ages. Yet very little changes. The river Lyon still burbles on merrily past the Roman Bridge (that isn’t in any way Roman – it dates from the late 18th century); the mountains were all the same shape, with a light dusting of snow hinting at winter yet to come; the Scots Pine trees were still where I remembered them being (and, more to the point, I’ve since learned that they’re a remnant of the Caledonian Forest). There are, however, yet more potholes in the road from the dam at the end of the Glen up and over to Glen Lochay and someone’s plonked a cattle fence across the way. So it goes.

I had some fun with the Pentax 50mm f/1.8 lens, using it for landscapes (not a usual choice for me) and closeup work, even using a hole drilled in the lens-cap to make it into a pinhole.

Ansel had his “Moonrise, Hernandez, Mexico” moment. On the way back along the glen, I had my “Moonrise, Glen Lyon, Scotland” moment: the dullest of grey fading light, a clear view along between the mountains, dark bluey clouds passing rapidly in the distance and the moon rising beyond. Better yet, there were two boulders – one to climb, from which the other made a nice foreground feature. Click. Or more accurately, cliiiiiick, click, cliiiiiiiiiiiick – the sounds of a long exposure HDR sequence (1s, 0.25s, 4s) to capture the contrast on the scene. Categorically the best photo opportunity of the year.

I drove back over Ben Lawers in the pitch black with the rain turning to sleet.

Glen Turret: Dark

Posted on by

Two of my twitter friends have developed particular styles – extreme dark low-key black+white rendition and negative inversion, respectively. It’s intriguing how scenes come out – a very different mapping from the usual realism.

Portknockie (3/3): Bow-Fiddle

Posted on by

I’ve left the usual photos to last, seeing as how everyone else has shot this scene before.

It wasn’t particularly easy; the tripod was struggling to stay steady in the breeze and the course of a few seconds between adjusting the camera, leaving it to stop vibrating and pushing the shutter remote release, the light was changing radically from dull shade to bright sunlight on the foreground rocks. Still, a moderately long exposure worked, eventually.

Herewith, four different ways of processing the same images.

Bluebells

Posted on by

A day out, today, with the Focus on Photography Perth meetup group. We parked in the MacRosty park carpark in Crieff and strolled along Lady Mary’s Walk, a dismantled railway line on the north side of the River Earn to the Trowan woods.

Many photos were taken. I was feeling a bit experimentalist, so deployed a couple of tricks:

  • Helios 58mm f/2 lens with lens-cap covered in many holes – this gives many superimposed images, a bit like a starburst filter; I thought it would work well with the small-scale textures such as repeating blue and white flowers
  • an infra-red filter – partly for long exposures in daylight (it’s similar to using a 10-stop ND1000 filter) and partly for the effect when shooting foliage with a strong red filter.

Herewith:

Glen Affric: Rockery

Posted on by

There’s an impressive outcrop of rocks (psammite and semi-pelite, looking rather like limestone) near the waterfalls in the River Affric. Some kindly soul had balanced these pebbles on a boulder on their way past previously.