I was never a fan of post-processing photos, possibly because I come from the one-chance era where you looked at a large slide projection and knew that most of the skill had gone into the preparation of the shot. Today, of course, it’s much different. We view 600 pixel-wide photos on crappy LCD screens and the image we’re viewing is one of probably 50 that got shot in succession. We view that photo as it passes from bottom to top, our eyes scanning for the briefest hint of something worth stopping at as we scroll. Because of that, processing that photo for an eye-catching effect is a normal part of todays smartphone-based social sharing process.
Sometimes the camera does that processing without you even knowing it. Other times there are simple effects that turn a so-so photo into something worth an extra few milliseconds looking at. Instagram was built on this type of processing. There are more complex methods too but the one I’m interested in now has only been possible in the social networking scenario in the last year.
Some years ago I learnt about HDR photography. I tried it a few times but it always needed a tripod, a static subject and some PC-based processing. Annoying. There was a trend on Google Plus too which took HDR + Tone-Mapping too far. Like a short-lived music-trend it passed quickly. Today, however, I’m shooting HDR photos from the hip. it’s handheld, quick, doesn’t require a PC and I’m loving it. You can argue whether the process of combining three photos and processing it in this way is natural or not but the results I’m getting in terms of feedback are very positive indeed. It’s fun, satisfying and effective and it’s going to get better. I can see a huge next-step for consumer HDR coming up.
Here are a couple of my early handheld 3-image HDR tests on a Nokia Lumia 925 using the HDR Photo Camera app. As I look at them on my monitor they aren’t as color-rich as when viewed on my (excellent, high-contrast) Lumia 925 screen so I’ve pushed the color saturation up a bit. On your monitor, if you’ve got a good one, it might look too much but in general I think they’re punchy and detailed.
HDR processed photo below without tone-mapping.
Here are two of the of the three original photos that were combined to make the HDR photo. Look how the sky is completely ‘blown-out’ on the ‘over-exposed’ photo (left) because of the need to capture enough light for the dark areas in the photo. No amount of processing will ever find those clouds in that white area. Similarly the ‘underexposed’ photo of the three (right) makes some of the dark areas of the image too dark.
Here’s the HDR photo that’s been tone-mapped for a bit of selective contrast enhancement. It’s good for dramatic effect but too much of this leads to that out-of-fasion synthesized effect.
Here’s one I tone-mapped and removed what color was in the original for dramatic effect. One of the originals in the HDR set (the ‘correctly exposed one) is below.
I’ve been enjoying the results from the Lumia 925 but I’m very aware that these aren’t pro-level HDR photos . Put into perspective though, these photos are impressive considering that they’re HDR, taken handheld and processed automatically in about 20 seconds, on a smartphone. The handheld part of the equation is made possible largely because of the optical image stabilization on the Lumia 925.
What I find really exciting about this is what could come next. One-shot HDR.
One-shot HDR is not currently possible in consumer-grade cameras because it would require at least two sensors in one body set to different gains. It’s a shame because it’s the only way you’re going to ever (easily) get an HDR photo of a moving subject. There is, I believe, a way though and it’s something Nokia should really be (are probably already) working on.
The ‘super pixel’ concept used in the Nokia 808 and Lumia 1020 has been a great way to process out noise and increase sensitivity of a small sensor. In the super-pixel, two, four, eight or more sensor pixels are grouped together and the results, effectively multiple versions of an image, are processed to create one better image. What if those pixels were set to different gain levels (equivalent to ISO) in order to produce four images of varying light levels. You’ve effectively got the source photos needed for HDR processing, in one shot. That’s the way to get an HDR photo of a moving subject.
One imagines that setting differing gains on sub-pixels is a huge technical challenge but I would place money on it being technically possible and when it happens it’s going to open up a whole new type of photography and enable HDR processing to be transparent to the end user. It’s perfect for smartphone users.
How to: HDR Photography on the Nokia Lumia 925
It’s not complex, and this capability is available on Android and IOS too. On the Lumia 925, however, you’ve got a much better chance of getting it right first time because of the mechanical image stabilization. I use HDR Photo Camera, an app that cost me just a few Euros. Version 3.5.4 is the current version and it has some optimizations for Lumia phones.
Simply hold the camera steady and don’t move between shots. (Ideally you would use a tripod but I’ve had good results so far.) Touch the area of the screen you want to have in focus and wait for the three (default) shots which take about 5 seconds. Note that moving objects in the images will leave a ghost effect in the final image.
After about 15 seconds of processing that final photo is ready and can be edited in the app by using the back arrow in the top-left of the frame. Editing options include 1) Contrast, Brightness, saturation and 2) A set of tone-mapping and effects. Each time an effect is saved a new copy of the photo is produced. The three original images are always preserved as is the originally processed HDR image.
To close then, here’s an image taken while writing this post, handheld from inside a building. Being able to shoot HDR so quickly and easily is clearly an advantage.
Nokia Lumia 925 kindly loaned by Nokia UK.