Photoblog 2.0

For quite a while art director and art agent types have been bugging me to publish an online portfolio. The complaint is that it is hard to find what I’m about as an image creator and photographer with all the stuff I’ve put on line. It’s true I have literally thousands of images on line and in the four years I’ve been blogging I have more than two thousand stories about photography. Yes, the material is tagged and searchable, organized with a taxonomy and human-readable site map, but even so it does not fit the concise and focused look of a top-of-the-line portfolio, which tends to be have relatively few images with some fancy (and flashy) user interface elements.

So last week I bit the bullet and decided to program my portfolio page and slide show in Flash. You can see the results on www.photoblog2.com, which as also serves as a new entrance portal to this blog.

As an experienced software programmer, how hard could it be? Well, in fairness I need to say “ex programmer”—it’s been years since I’ve coded much of anything. And, at the possible expense of losing my über geek status, I’ll admit I found the Flash development environment a beast. Not so much the ActionScript programming language, which is a relatively clean implementation, but the whole construct of what goes where, with a stage and timeline in every application, and so on.

The heavy lifting in my application was done with a set of add-on Flash components from SlideShowPro, which are very elegant, but also complex, and with documentation that leaves a great deal to be desired.

I wanted something simple, elegant, and clean to best show my work. Sometimes simplicity is the hardest thing of all to achieve.

Well, it was a week lost to Flash development: but at least the beast is done, and I learned how to do it!

Late in the afternoon of a bright autumn day I arrived in Yosemite Valley. The valley was already in shadow, with only the tops of the surrounding cliffs lit by the sun. I stopped along the banks of the Merced River. With my camera on my tripod, I snapped five exposures of the scene, all at the same aperture (f/7.1). My exposure time varied from 1/15 of a second to 1/125 of a second.

The longer exposures captured the details in the shadows, but blew out the highlights on the cliff tops and the sky, while the shorter exposures rendered the sky acceptably, but lost all nuances in the reflections in the river to darkness. My plan was to combine the exposures to create one image with the best characteristics of each individual exposure.

Yosemite Afternoon, photo by Harold Davis. View this image larger.

HDR

Combining multiple captures to create an image with an exposure range beyond that possible in a single capture is known as High Dynamic Range imaging, or HDR for short. The trick is to compress the extended range into a single image that is pleasing, will display on a monitor, and is reproducible. Note that the exposure latitude within a single RAW capture also gives rise to the possibility of using HDR techniques using different versions of the one RAW file as the input, a technique that I’ve dubbed multi-RAW processing.

Hand HDR

Whether combining different exposures, or different versions processed from a single exposure—or even both these techniques at once—my approach has been to work in Photoshop to use layers, masking, the Gradient tool, and the Paintbrush tool to combine the variants. You can see an example of the results of this hand-crafted approach to HDR in the six-exposure blend that I used to create Yosemite Morning, taken the day after I shot the series used to create the Yosemite image that accompanies this story.

I’ll be writing more about the details of my hand HDR process in an upcoming book—I also teach the technique in workshops—but for now let me mention some downsides: it is labor intensive, time consuming, can look funny if the layers aren’t masked very carefully, and can be close to impossible to achieve in areas that involve complex interconnected details in mixed light.

Photomatix

Since we live in an age that tends to want instant results, most people try experimenting with software the does the HDR for them. I’m no exception, but I’ve been unimpressed with Photoshop’s HDR automation.

So I was excited recently to get to play with Photomatix, which is probably the leading HDR software. The Yosemite image above, and the floral close-up below were both created in part with Photomatix. As you’ll see, the words *in part* are crucial to understanding Photomatix’s place in my scheme of things.

View this image larger.

With Photomatix, HDR generation is a two-step process. You open the images in Photomatix, and the software generates an HDR composite. Then, in a process called “tone mapping”, you tweak the settings used in the mathematical algorithms that reduce the tonal range in the combined image in order to generate a single attractive and reproducible version.

Workflow

As a practical matter, I found Photomatix’s rendering of my RAW files unacceptable. So my workflow went like this: I opened the set of images in the Adobe Camera RAW plugin, applying the same settings to each (experimenting with different RAW conversion settings on each file included is also possible, of course, although it adds more variables and complexity). I opened the files that resulted from these conversions in Photoshop, and saved them in the TIFF format (because Photomatix doesn’t read native Photoshop PSD files).

Next, I opened the TIFF files in Photomatix and generated the HDR composite. As the documentation warns, the HDR image doesn’t start out looking too good, so I worked to tone map it for more attractive characteristics. When I was satisified that the image was the best it could be, I saved it as another TIFF file.

Combined Approach

Some parts of the resulting HDR image were pretty wonderful (for example, the trees on the right). Others, not so good (the sky had a burnt, burnished quality, and the water was murky). I ended up layering-in versions in Photoshop to fix portions of the Photomatix generated image (the same general remarks are true of the floral image that also accompanies this story).

If my workflow with Photomatix sounds like a lot of work, you are right, it was. Then again, I’m happy to work if it helps my work (if you catch my drift).

Life is simpler but less rich

Also, my life would have been simpler in Photomatx if I’d shot in-camera JPEGs. The truth is that the markets for my work often require extremely high resolution, and JPEGs just won’t do. I’m almost never happy with JPEGs compared to my results when I do the RAW conversion.

Conclusion

Paradoxically, I’m left with an appreciation both for what Photomatix can do with HDR, and for the limitations of the software. I’m sure I’ll be using this software to process some portions of my imagery, just as I’m sure that my final versions will require hand work and layer masking with other versions of the files.

If you are an image creator who cares about your craft, the limitations in HDR software amounts to a good reason to learn hand HDR—combining many different versions shot at different exposure times, and processed individually from hand-tweaked RAW conversions, using layer masking—even if you expect to primarily be using automated HDR programs like Photomatix.

When you use Photoshop, nothing is more important than the ability to make selections. As a simple example, when you want to make a composite by moving a person from one background onto another, you need a way to select the person—in other words, to tell Photoshop which pixels you want to move. Besides this kind of large-scale selection, selection is used on a much smaller scale in Photoshop to control the areas you want to change in an image, and for a variety of other reasons.

Since you need to be able to select in Photoshop, Photoshop provides a number of nifty selection tools. These include a Magic Wand Tool, and the ability to select on the basis of color range. But it is a sad fact of life for Photoshop addicts like me that we spend much of our life on time consuming and tedious hand selections. The task is made even more difficult by the issue of edge treatment. The edges of a selection should usually be blended using a gradient effect, or your selection will appear jagged and unnatural.

It’s not intuitively obvious, but making a selection in Photoshop is logically equivalent to creating a layer mask. Both selections and layer masks are stored as grayscale information. If you have a selection, you can convert it to a layer mask (I’ll explain how in the course of this review); going the other way, it’s easy to convert a layer mask to a selection (by applying the layer mask). For the real technophiles among my readers (I was almost going to say “alpha geeks” but restrained myself), a layer mask is the same thing as an alpha channel. Hmmm! Selection = Layer Mask = Alpha Channel.

My preference is to work with layers and layer masks because this is a more flexible option than working with a selection cut out on a single layer. But to get the layer mask I need, I often have to start with a complex and time consuming selection.

With this background in mind, I tried out Fluid Mask, a Photoshop plugin (it also runs in standalone mode) from Vertus that is supposed to ease the pain of selecting. Read on for an overview of how the software works, and for my evaluation.

View this image larger.

The flower you see above on black, a Gaillardia, was originally on a busy green background (because I photographed it in my cramped side garden). The original image following RAW processing is shown below with the background I wanted to replace.

As a first try with Fluid Mask, I decided to try selecting the flower to cut it out and put it on a black background. But before I show you how this worked, I need to make a disclosure. Disclosure: Vertus provided me with the Fluid Mask software for free, as well as some complimentary individual training (but see the note below about the availablity of free online training for anyone).

Once Fluid Mask has been installed, you’ll find it as a menu item on the Photoshop Filters menu (at the bottom of the menu items, along with any other third-party plugins you may have installed). With an image open in Photoshop, when you fire up Fluid Mask, Photoshop temporarily closes (“to save resources”) and the Fluid Mask window shown below opens. Note: As a matter of general Photoshop practice I’d advise creating a duplicate layer before invoking Fluid Mask.

Fluid Mask drew blue lines on this image, indicating the edges that its automated analysis found. (You may need to look closely at the screen capture to see these lines.) The basic Fluid Mask idea is to draw on your image using three different colored brushes. Green means that you are keeping the area, red means that you are throwing the area away, and blue is used for an edge that needs to be treated specially. Here’s how this might look on a corner of the Gaillardia image:

So, this was my first solo flight with Fluid Mask, and I didn’t get everything quite right. While the Gaillardia is really a pretty easy selection problem, to do a good job using the normal Photoshop tools would have taken me an hour or two. In Fluid Mask, it was about five minutes. But I did cut too much out of the flower interior by mistake, as you can see by comparing this cut out with the original or final versions:

When I applied and saved my work, Photoshop opened back up, and I was able to quickly fix my botch. I converted my selection to an alpha channel (layer mask) by clicking in the thumbnail in the Layers palette with the Apple key held down (Option key in Windows), and then clicking the little alpha channel icon on the bottom of the pallette (third from left, you can see this in the capture below). Then I added a black layer between my original flower and its masked duplicate. A reveal-all layer mask on the black layer allowed me to “paint-in” the few small areas from my original that I had missed in Fluid Mask. All this took about two minutes.

Bottom Line
I recommend this product. I expect to use it every time I have a reasonably complex masking or selection challenge, and I’m sure that I’ll become a more skilled user over time. For me, owning this product is a no-brainer. (o:

Pros: Greatly speeds selecting and leads to better quality selection.

Cons: Complicated to learn, without an adequate manual. The good news: online interactive tutorials are available free five days a week.

Product details: Downloads from Vertus cost $239 (in the US) for either Windows or the Mac.