HDR: High(er) Dynamic Range Photography - A few tutorials but mostly a display of my HDR experiments

May 19

Heading north has always been the path to mystery, to silent eerie forests and shadow-filled canyons, to myths and legends beyond comprehension and to the cold bite of unforgiving winds or the penetrating humidity of endless fogs. As much as the South echoes in my mind of warm seas and aimless pursuits, the North is made of exploration and danger, and magic, and sorcery.

So when I headed across the Burrard Inlet last week-end in my quest for a few stamps, it was with the firm intention of balancing my time in touristland with time in the other world; the secret, often ignored and always quiet space that lies just at the edge of civilization, right next to our daily madness arena and yet so remote in the collective consciousness that it might as well not exist. It always puzzles me how easy it is to step from crowded paths into peaceful and haunting side tracks. They are there, all around us, all the time. One only needs the will to see them.

The Capilano Suspension Bridge was its usual self, popular, wobbly, long, overlooking its canyon from hundreds of feet up. I crossed it, got my stamp, came back, and walked up Capilano Rd for a few hundred meters to the branching left turn. Because I, was going down. Soon, I left the already quieter paved road and ventured onto a narrow hiking trail. I was alone, at last. It had been 29°C when I left the West End around 4:00 pm, this being the warmest day of the year so far. But as I pushed deeper into the forest and closer to the bottom of the gorge, and the roaring of water, the air chilled and I knew magic had begun. Sorcery too, maybe, but would I ever know?

The sun was about to dip behind the mountains to the east and had serious trouble reaching as deep down as the river. Shadows grew around me as I descended swiftly, taking deep breaths and smelling with great pleasure the pine trees and their moss. It wasn’t difficult, then, imagining a world of Elves and Goblins and Trolls, alive around me, watchful and whispering as I passed by. The city had moved back into my mind to the state of a theory, an abstraction merely remembered but not entirely possible. It might as well have been a thousand miles away.

Surprisingly, when I finally made out the white foam of rushing rapids below me, some light seemed to reappear. The river caused a relative clearing in the tall trees and a few late rays shone bravely enough to bring some gold back to the overwhelming green of the foliage and moss and water. I took a few pictures and walked upstream, 50 feet or so above the rapids on the steep eastern bank. Eventually, I reached a small wooden bridge over the Capilano river, which I didn’t cross. I knew exactly where I was, the salmon hatchery was up ahead to the right. Having found it, I took a last long look and walked back up slowly, leaving magic behind and re-acclimating myself to noise and people.

Back on Capilano Rd, I lazily hopped on the bus and kept going uphill to the bottom of the Skyride. Grouse would yield another stamp. While waiting for the next red cable car, I paid the poor wolves a visit and promised one to put his picture on my blog to cheer him up. I wasn’t sure, but having just come from the enchanted forest below, I thought he might have been an old king, caught off guard by some evil witch and held captive by a terrible spell, to his slow agony and our ignorant pleasure.

Then it was time to rise. The ground faded under my feet and the horizon grew wider and brighter. The sun was setting at precisely the moment we passed the second pylon and when we finally entered the summit station, it had disappeared behind the Lions. I walked around, aroused by so much fresh air, revived by the proximity of the mountains and mesmerized as always by the beauty of the scenery.

But I had a rendez-vous to attend and I sat down with a tall murky beer at the Altitudes Bistro, silent, lost in thoughts and ever so grateful. It was my first time back up since coming with Marie the previous fall. So much had been set in motion, then... I took a deep breath. Magic, it seemed, did not only live in mysterious woods. It had followed us up here, that night, and always would stay. I sensed it all around. It was talking to me. I answered and smiled, looking to the East. Then I finished my beer and headed back down. Magic followed. Or maybe it lead. I know where it’s going.

2008-05-19 22:27 • Posted by Vince in Always: & HDR: & Photoblogs: & Vancouver: 2 Comments » Toggle display • Reply

Jan 3

Timothy Farrar has finally released the newest version of his fantastic digital darkroom tool, FFDD6. Of course I’m way too busy these days to afford the time necessary to process HDR photos, but it’s exciting news and I can’t wait to test run the script on the upcoming South Africa shots!

Timothy and Kathryn are also planning to host an online FFDD HDR photo contest which promises to be totally cool, since I’ve so far only seen pictures rendered by the masters themselves and I will be quite curious to see what others are doing with the script...

So in the meantime visit their web site but also stay tuned for more HDR photography, made in South Africa, coming to a Coriolistic blog near you this spring.

2008-01-03 22:10 • Posted by Vince in Bits and pieces: & HDR: & Photography: No comments yet »  Post one!

Jul 22

They’re big, they’re high, they’re sharp and they reign over the local landscape like as many kings on their respective kingdoms. They are the volcanoes of the Cascades mountain range.

My last visit to the American part of the Pacific Northwest dated back almost two years. I had driven around Mt. Hood, observed Mt. St. Helens from a distance, glanced at Rainier from the highway and marveled at the fact that Baker was not only so close to the Canadian border, but to Vancouver itself. However since then, even nearby Mt. Baker had remained out of reach and almost hypothetical.

It took a very serious reason to lead me back south across the border. I went to visit a very dear friend whom, I thought, might need some company and support. It turns out that while company is always welcome, support is for the weak, and weak she isn’t. Kudos to her, and my utmost admiration and respect.

From Olympia, WA, we decided to go for a ride to Mt. Rainier, despite the heavy rain and low ceilings. If we couldn’t see it, we would at least stand at its foot. A pleasant drive lead us from the bottom of Puget Sound into rolling hills announcing the proximity of the giant. The forest got thicker and greener and the clouds seemed to be thinning, but still nothing appeared above us. The mountain remained invisible, hidden in its lingering shroud.

Wildlife was everywhere even before entering the park. The rain had stopped and the sky was hesitant. The slope steepened, the road began to twist and turn and we arrived at Paradise, highest civilized point south of the mountain, altitude 5400 ft.

Deciding to go for a short walk on a looping trail, we hoped for a sneak preview of the Nisqually glacier. By the time we got to the view point, the clouds were lifting further, revealing the mountain’s base and some blue glacier ice soiled with brownish debris. We grabbed a bite to replenish our energy supply and chose a new hike, longer and higher, but conservative enough for our shape.

A deer passed nearby, then a mountain marmot came out of nowhere, crossing the path just behind us to go gorge on flowers below. The clouds were still receding. Finally, 4,392 m high Mt. Rainier appeared in most of its majestic height.

But energy was fleeting. This was enough for a start and quite a remarkable effort in itself. We walked down to the car and headed slowly back to the lowlands, stopping here and there for more deer and marmot pictures, for elks, for hummingbirds and for pizza.

The following day, the rainy drive back to Vancouver took me six and a half hours! Traffic is an evil thing. But I had food for the road and music to play.

Here are the first pictures (but you should start the slideshow at the top), I’ll post the rest soon.

2007-07-22 21:18 • Posted by Vince in HDR: & On the road: & Photoblogs: 2 Comments » Toggle display • Reply

Jul 15

There’s a lot more to sunset than meets the eye. From immemorial times, mankind has watched sunsets with a twinge of the heart and a sigh, while sunrises were left alone and generally ignored. Why is that?

As a race, we are dreamers, yet we do not know very well how to empower ourselves and make our dreams come true. We rely on hope and we pass our wishes on to faith. But when the time comes to act and think bold, we get caught up in the moment’s difficulties and lose sight of the big picture.

That’s why sunrise has always been relatively unseen. By the time the sun rises, we are busy stressing out about the day that lays ahead, focusing on immediate goals that speak more of survival than greatness. Sunrise, for many, has become a symbol of labour, heat, struggle and harsh reality. It is a time of day at which we must painfully awaken, attempting to chase a night’s dreams away by drowning them in coffee and diluting them with the brutality of a newspaper. It’s time to perform and to act. It’s time to long for the next sunset.

At night, on the other hand, when the blazing sun finally dips under the horizon, all that suffering is momentarily left behind. We can relax. The colours last longer than in the morning as if the sky knew that time has finally lost its cost and the pace of our lives can slow down and soften. Whatever our performance of the day, it is over now and it will not matter again until dawn. What is done is done, what is said is said, what is missing can still be found in the new dreams of the falling night. Hope or despair can invade the heart, and sunset will make these emotions stronger and more real than the sunrise ever could, because souls are left with nothing to do but ponder.

Sunset is a time to evaluate, a pause in the race, a break in the routine. And as Christopher Columbus said of the ocean, it will bring each man news hopes, as sleep brings dreams of home.

2007-07-15 13:24 • Posted by Vince in HDR: & Photoblogs: & Schtroumpfissime: & Vancouver: 4 Comments » Toggle display • Reply

Jun 30

Here are the few HDR pictures I chose out of the 105 I took that night. Common theme, different light, as the sun went down through the clouds and disappeared behind the mountains. They were shot from Second Beach, on the western side of Stanley Park, facing English Bay and with Point Grey and Bowen Island in the background.

2007-06-30 21:13 • Posted by Vince in HDR: & Photoblogs: & Photography: & Vancouver: 2 Comments » Toggle display • Reply

Jun 29

By popular request, and also to a lesser extent because I’ll enjoy doing it and might even benefit from it myself, I’ve finally decided to write my own modest HDR tutorial. In order to do so, I must make an assumption and two statements. First, I suppose that my esteemed readers will have found my previous HDR-related posts, particularly Still playing with exposure blending and HDR, HDR photography meets quantum physics and Discussing HDR photography. Next, I solemnly declare being a newbie at HDR and warn said readers that my rambling should be taken with a grain of salt, if not of 400 ISO. I strongly urge anybody interested in HDR to check out the links I’ll provide throughout the post because they are quite comprehensive and in many cases much more thorough than I could ever be. I must also emphasize that this cannot really be a tutorial because most readers will not yet have available the scripts I’m referring to, and could not compare or practice. So I’ll call this a comment on my workflow rather than a tutorial.The Photomatix HDR resulting image

My first contact with HDR was an accident, or rather a coincidence. I was scrolling through albums on Flickr and came upon a category of rather stunning - while a little surreal - photographs. I researched the subject and immediately knew I was going to like it. It was called High Dynamic Range. It opened new doors and unleashed a photographer’s creativity in ways that very much appealed to the landscape maniac I am.

Further research soon revealed that HDR was in its infancy, and that much debate surrounded it. I began looking for tutorials and actual tools. Three main streams emerged from the many pages I read: it seemed HDR pictures were most often generated via either a piece of software called Photomatix, through Photoshop’s integrated merge tool, or via other less known scripts or programs. The Photoshp Merge to HDR resulting image

I started by playing with Photomatix (HDR blend above) for some time but while it created fascinating images, the necessary tone mapping made them a little abstract and painting-like. The program is very good at rendering complex textures and does wonders for interior scenes in artificial lighting but I find it too extreme for normal landscape photography. There’s an excellent tutorial and interesting images at Stuck in Customs.

So I went on to try Photoshop’s « Merge to HDR » tool (left); it was all right but the results still didn’t impress me that much.

Then one day, I found Timothy Farrar’s brilliant set of Photoshop scripts and actions, Farrar Focus Digital Darkroom 5. I dropped everything else I was doing and immersed myself in HDR, learning the art, refining my workflow and experimenting with the new camera I ordered along with the script. ;- ) That was a year ago.

I’m still passionately shooting most of my landscape pictures in HDR and every day I learn a new trick or technique. So my so-called tutorial will concentrate more on workflow and personal preferences then on HDR itself as a technique. Because of the radically different nature of tools like Photomatix, Photoshop and the scripts I use, some of the steps I describe might not apply to someone using a different tool. Bear with me however, and do yourself a favor: if you are considering HDR seriously and are not completely satisfied with what you’ve found so far, you owe it to yourself to have a look at Timothy’s scripts. As far as I am concerned, they simply rock.

I use a Canon Digital Rebel XTi (400D) DSLR and my only lens for the time being is the cheap 18-55mm that came with the body. A sturdy tripod is a must and I carry it everywhere with me. I also use a cable remote in order to avoid camera shake, as well as mirror lock once in a while. The camera is always set to manual mode to give me full control on depth of field, and I obviously shoot RAW pictures with the camera set to the Adobe RGB color space (closer to the giant ProPhoto I use in Photoshop.)

As long as I am doing landscapes, I systematically bracket all my exposures, taking a series of 3 shots for each scene: underexposed by 2 f-stops, correct metered exposure and overexposed by 2-stops. I make sure to vary speed rather than exposure in order to keep depth of field constant. When initially metering the scene and deciding on where to start the bracket, I do my best to « expose (to the) right », choosing to offset the 3 exposures slightly towards the right of the histogram to maximize signal-to-noise ratio. More than 3 exposures would be beneficial for the technique I use but I haven’t gotten that far yet and I will need an even better tripod because the extra manipulation required will increase the risk of moving the camera between shots. Timothy Farrar wrote a great page on the selection of adequate bracketed exposures for HDR blending. Below are the 3 RAW exposures captured for this page’s example:

Bracketed exposure (+2)Correct bracketed exposureBracketed exposure (-2)

Once back at the base, the magic begins. The current version of Timothy’s scripts, FFDD5, runs from Photoshop and allows me to open 3 RAW files via Camera Raw, leaving them untouched and linear, and then blend them into a 16-bit HDR digital negative. Like any such file, the resulting negative still needs development but it now has a much better tonal range than the originals did individually. There is no tone mapping involved since the process is different and the image generated isn’t actual HDRI, which would be unreadable by my screen. We have simply combined the best of all three shots and end up with a dynamic range that is closer to 8 stops, as opposed to the 5 we started with.

Now some of the other actions written by Timothy come into play. Again his site has a very thorough explanation of the development process, but I’ll resume it by saying that I add adjustment layers on which I set brightness and contrast separately, as well as saturation. This is similar to using graduated Adjustment layersneutral density filters in the field, only much more flexible and powerful. For example, to achieve a pleasant, natural looking sunset, I’ll typically have to set brightness for the mid-tones, boost contrast up, and then darken the sky and lighten the foreground. I sometimes end up with up to 10 or even 15 adjustment layers (right) - which are non destructive - that I’ll only flatten at the end.

Here, a short parenthesis is in order. I have been testing the new version of the blending script and it’s quite amazing. Working on DNG files instead, it is much more intelligent and allows for better batch processing. It will identify properly named groups of files in a folder and its subfolders, blend them accordingly into a high-res digital negative, and also generate a low-res version of the picture to which I can then apply my adjustment layers much faster. I save the newly developed low-res file with its layers and go back to the script to make it generate a high-res version of the original blend, completely developed and ready for final tweaking. Quite awesome.

My now developed digital negative routinely receives a dose of denoising combined with some sharpening, both of which are done by - yes you guessed it - more actions from FFDD5. However, I must insist on the fact that the HDR blending achieved by FFDD5 is by itself the most amazing denoising tool I’ve ever encountered. The process easily beats both Photoshop’s internal noise reduction tools and third-party plugins, and once again it is non-destructive. With FFDD5, noise suppression is obtained by adding tonal range to an image, rather than by suppressing existing noise in a conventional way which unavoidably causes a loss of sharpness and slight blur of the image. So in the end, while the main purpose of HDR blending remains for me the gain in tonal latitude required to render landscapes the way I see them, I value the noise reduction just as much, especially with printing in mind.

The following is a 200% crop of the results (keeping in mind that my lens is soft): both sides were processed with the same brightness, contrast and saturation adjustment layers. On the left is the correct single exposure from the series of 3 bracketed ones; on the right is the final blended HDR exposure, denoised and sharpened.

200% crop of single image (left) and HDR (right)

Last, I’ll straighten a tilted horizon, reduce lens distortion if needed, remove sensor spots if any and rethink my framing one last time, almost always aiming for compliance with the sacred Rule of Thirds or even attempting to ace the elusive Fibonacci spiral-based Divine Proportion.

The final HDR image using FFDD5My final image (left) is saved as a full size flattened TIFF with the ProPhoto color space embedded, and then reduced to web standards for my blog, a JPEG image of around 800px horizontal size, compressed at 90% quality in the sRGB space.

I hope this will have helped a few people find inspiration and motivation to explore new fields. I might sound biased towards my favorite HDR tools, and I am. With a bit of luck, my oversimplification of things will not have annoyed the pros or offended the authors of such great scripts.

Someone was recently commenting on Kodak’s new color sensors that will be hitting the market next year, and new digital cameras soon ridding themselves of their low-light slavery to the good old flash. HDR is the logical progression for in-camera picture optimization. It’s only a matter of time. Wait and see…

In the next post, I’ll add the usual slideshow of the final images taken along with the ones used here.

2007-06-29 22:29 • Posted by Vince in HDR: & Photoblogs: & Photography: & Vancouver: 4 Comments » Toggle display • Reply