5 --> DRO / Auto HDR --> DRO Auto. (or access it from the Fn menu if it hasn’t been configured to not be there).
Sony offers two different features which attempt to address the problem of “My picture doesn’t look the same as what my eye saw!”: The first is called Dynamic Range Optimization (which operates in an intelligent way to brighten the shadows), and the second is the High Dynamic Range technique which takes three images of different exposures and merges them together in-camera. Both features have their tradeoffs: DRO works great for moving subjects, whereas HDR images (for still subjects) don’t have as much noise in the shadows. The whole shebang (or Magilla, or enchilada) is explained in this chapter.
The advanced Dynamic Range Optimization feature first appeared in the A100 back in 2006, and I have grown to really love this feature (in fact I hardly ever shoot with it off!). It can help you make the best of un-ideal light, and it can save you countless hours trying to do the same thing in post-processing on your computer (which is not easy to emulate). Unlike the original implementation on the A100, the A6300’s DRO feature gives you more control: You have “AUTO” plus five manual settings, ranging from “the most conservative” to “the most aggressive”. Sony’s Image Data Converter software also allows you to perform a similar adjustment to your RAW files using your computer after-the-fact, but as the examples in this Chapter will show, the results of the in-camera DRO processing are usually more effective.
Before I get into the technical stuff about how it works and where it fails, I should tell you how to set this feature: MENU --> 5 --> DRO / Auto HDR --> DRO Auto. (or access it from the Fn menu if it hasn’t been configured to not be there).
TIP: DRO works in all movie modes except the XAVC S HD 100p or 120p modes. |
Let me share with you some DRO success examples. Figure 14-1 and Figure 14-2 are images where DRO has made the image better right out of the box in a high-dynamic-range scene – no additional effort on my part was required.
Figure 14-1: This is a good example of a scene that can benefit from DRO. I used DRO Bracketing “Hi” to produce DRO Levels 1, 3, and 5 to “bring out the shadows” in this outdoor scene. For this shot I think I like Level “1” or “3” the best – 5 looks a little too artificial for my tastes. |
Sony doesn’t provide much technical information about this feature, and so through much experimentation I have learned to “see” in which situations the feature would provide the most benefits, and (perhaps just as important) know under which situations the feature will produce just awful-looking results. In this chapter I will share my knowledge and experimentation with you, so you too can get the most out of this remarkable feature.
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Figure 14-2: DRO can act as an effective “fill flash” to only the dark parts of the picture when the lighting is non-ideal. It can also make things look natural in extremely low light and high ISO (upper right). Bottom row: Another example of making pictures look like you remember them (left and middle), and improving a subject in shade (right). |
First, let me get some misconceptions out of the way: DRO only works with information that the sensor has already captured. It does not give the sensor a wider dynamic range. DRO simply takes the information that’s already there and makes the darker areas a little lighter in a fast and intelligent way.
So how does it work? Those of you who are familiar with the Tone Curve tool in programs like Photoshop, Lightroom, or Sony’s Image Data Converter software, you could affect the brightness of certain parts of the image, while not affecting the other parts (as shown in Figure 14-3). Most people use the tone curve to increase contrast (making the blacks blacker), but the tone curve can also be used in reverse – to make the blacks less black. And while the image in Figure 14-3 certainly doesn’t benefit from making the blacks lighter, images in future examples certainly will.
Figure 14-3: The tone curve has the ability to change only the blacks and leave everything else alone. This is the principle behind the most basic DRO setting, except it happens in-camera and is designed to LIGHTEN the blacks, not darken them. |
That is exactly what DRO does: in certain circumstances, the algorithms in the camera’s image processing chip will examine the brightness range of the image and, if it feels the image will benefit, will evaluate and map out every light and dark area of the image, and apply a local gamma curve to each individual area. Considering all the computation involved and the number of megapixels on the sensor, the speed at which the camera analyzes and processes the image is actually quite an achievement. (And the camera does other image processing wizardry too, like correcting for distortion and chromatic aberrations in the lens after you shoot.)
“DRO Auto” will only kick in when the camera decides the images can benefit from it. This is in direct contrast with the manual DRO settings (Levels 1-5), where the camera will dutifully analyze the image pixel-by-pixel and lighten certain shadows and contrast areas it finds by a pre-determined amount, regardless of whether it feels the image will benefit. You can manually set the DRO manual settings from “1” (doesn’t brighten the shadows much) to “5” (where the shadows are lightened so much that the scene might look unnatural).
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Figure 14-4: Another DRO example – Level 1, 3, and 5. |
Does DRO affect RAW files? No. Also, you should be aware that Sony has a DRO-like feature to their Image Data Converter SR software so you can play with this setting in the comfort of your office instead of in the field. The results it produces aren’t quite as good as the in-camera algorithms, and it takes considerably longer to do, but at least you have the option.
Like the SteadyShot feature, Dynamic Range Optimization is not a panacea, and not all images will benefit from its application. The following should be kept in mind when considering using any of the DRO settings:
Noise is almost always more visible in the shadows; and when you amplify the shadows (as the DRO does) the noise will become much more apparent as well (Figure 14-6). This is an unavoidable consequence of the technique; to minimize this noise it is recommend to shoot at the lowest ISO settings you can (or try HDR if your subject is not moving – covered in the 2nd half of this chapter).
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Figure 14-5: Two situations of extreme brightness ranges which were able to trigger the DRO Auto algorithms into lightening the shadows. Not all scenes will trigger it. The mode was designed to be a “set it and forget it” feature, where the camera will invoke it when needed. I tend to keep the camera on DRO Auto as my default setting. |
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Figure 14-6: DRO can also bring out some undesirable qualities. Noise, which is always strongest in the shadows, gets amplified with any level of DRO (above, right). On the other hand, this feature gives you a fighting chance of getting usable images in the worst kind of light. |
Figure 14-7 shows a scene where the entire range of DRO options (including “OFF”) are used so you can get a feel for the effect of each setting. I strongly encourage you to do similar test shots of your own – DRO takes awhile to acquire a “feel” of when to use it best (and when not to use it), and this kind of experimentation is the only way to acquire it.
Q: Gee, there are so many different choices regarding settings, and they all produce such different results! How in the world will I know which one to use for any given scene?
A: It is difficult to say; every situation is different and in my experience, no single setting is optimal for all images. While trying different values in the field and examining each afterward on the camera’s display can work, it can be very time consuming, and we all know that images on the camera’s display can look very different from the same image viewed on the computer screen or when printed.
Figure 14-7: DRO has many different settings. Auto makes very, very conservative adjustments to ensure that the feature never calls attention to itself. The manual settings (Levels 1 through 5) allow you to use the feature more forcefully, making the image look more like the way you remember seeing it. |
What I find myself doing is keeping the camera set to DRO Auto almost all the time, and then when I encounter a scene with tricky or splotchy lighting I’ll save time by using the camera’s DRO Bracketing feature. When activated via Fn --> Drive Mode --> 
or 
, the camera takes ONE picture, processes it at three different Level DRO settings, and then saves the resulting THREE image files onto the memory card.
Figure 14-8: More examples of where DRO has made a positive difference. |
To hedge my bets in tricky lighting situations, I will often shoot DRO at various Levels with RAW & JPG, so in case I decide later that the image looked better without DRO (it happens), I can always have an unmodified version to tweak later. Of course this slows down the camera and consumes memory cards quickly in the field, but for some shots it’s just better to have options.
Q: Under what circumstances have you found the DRO most useful?
A: When shooting in low, splotchy light without a flash, the DRO Levels 2 or 3 makes the images look much more natural than without. Even High ISO shots look better (although if you’re not a fan of high ISO noise, you won’t like this effect at all! The noise in the shadows is amplified right along with the detail.)
Q: Does the DRO processing affect RAW files?
A: RAW files are NOT affected if you’re shooting with DRO. (Well, that’s the official answer, anyway, but this 2007 article from David Kilpatrick explains that the camera will underexpose the RAW file a little bit to make sure the highlights don’t blow out: http://tinyurl.com/6mm47bw The underexposure may be difficult to see because raw processors like Sony’s Image Data Converter will make it a bit lighter when showing the image to you.)
Figure 14-9 In the outdoors, when shadows can be annoying, DRO does to the picture what our brain does with the signal from the eyes – it makes shadows not call attention to themselves. (And apparently it straightens buildings, too! :-) ) |
Q: You mentioned DRO bracketing and shooting RAW & JPG. Any disadvantages to setting the camera to a DRO setting and then shooting RAW only?
A: Well, yes, there are huge disadvantages in my mind. When you play back the RAW file you just took, the camera won’t show you the RAW file as you might expect – instead it will show you a DRO-processed thumbnail that’s embedded in the RAW file. (The histogram will reflect this processed thumbnail as well, and not the RAW image). But when you get back to your computer, you’ll see that the RAW file looks COMPLETELY different from what you saw on the back of the camera, and it might take you a considerable amount of post-processing to get the image to look as good as the thumbnail which was produced in-camera. (As will be seen shortly, the Sony-supplied software to give you DRO-like features on your computer won’t give you the same results as the DRO algorithms in your camera.)
Q: Do you have a favorite DRO Level setting?
A: Other than DRO Auto, DRO Levels 3 and 4 seem to produce the most pleasing images for me most of the time. Like everything else, though, It All Depends upon your light, your subject, and the vision of the final image you have in your mind.
Q: Are you telling me that DRO Auto and the DRO manual level functions do a superior job compared to a post-processed RAW file using time-honored conventional tools like Photoshop?
A: Well, in theory, you should be able to produce identical results, but the reality is that it can take an experienced computer operator tens of minutes (often longer) to do what your camera can do in a fraction of a second. That is because the traditional Curves tool operates on the whole image, whereas the Sony software breaks down the image to the pixel level and applies individual corrections locally instead of globally. Maybe one day Sony will supply us with IDC software that implements the same algorithms as what is built into the camera, but in the meantime, the in-camera DRO tends to produce the better results.
TIP: DRO actually works in movie mode, both in DRO Auto and using any of the five manual settings. Easier than providing a physical fill light. :-) |
If you look closely at the first three images of Figure 14-7, you’ll see hardly any change between DRO OFF and DRO Auto. Why is this? Well, as mentioned at the beginning of this chapter, DRO only kicks in when the camera thinks it’s warranted. And, as I discovered the hard way, it can be very difficult to know ahead of time which scenes will trigger these settings
Figure 14-10: Too much DRO can cause colors to saturate and increase the noise substantially. |
and which ones won’t. It took me two days’ worth of intense shooting just to come up with a few good examples of what it can do when it’s working (see Figure 14-5).
That’s why I was quite thankful when Sony started including manual DRO Level settings on their cameras. With these settings, YOU can decide when it gets used, and not wonder if the camera was invoking it.
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Figure 14-11: Another example of where DRO looks bad. The funny thing is, it’s very difficult to know without trying whether any level of DRO will help or hurt a shot. A good rule of thumb, though, might be “If the lighting is insanely difficult to begin with, DRO will likely not be much of a help.” |
Too much DRO can blow out colors and increase the shadow noise to unacceptable levels. Check out the examples in Figure 14-10 and Figure 14-11.
Recall the “Sunset” Image Style (described under “Creative Styles” in Section 6.26) adds reds and yellows to the image to enhance the sunset somewhat. A very cool effect comes when you combine DRO Level 3 with the Sunset Image Style as shown in Figure 14-12. Try it!
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Figure 14-12: I combined Sunset Mode (which adds reds and yellows to the image) with DRO Level 3 so the subjects wouldn’t look so silhouetted. The left image is how the image looked out of the camera, with no additional post-processing. The center and right images show another example, shot in “Standard” and “Sunset” images styles. |
As mentioned previously, Sony has provided us with a “DRO-like” algorithm that can be invoked from Image Data Converter SR.
That’s the good news. The bad news is that the software algorithms in Image Data Converter don’t produce the same results at all. See Figure 14-13, and again I refer you to David Kilpatrick’s excellent article at http://photoclubalpha.com/2007/11/01/advanced-dro-the-a700s-magic-bullet/ for even more examples.
Figure 14-13: In-camera DRO (right) cannot be duplicated by processing the RAW file with Image Data Converter’s “DRO” feature (center). |
Figure 14-14: The best use for the HDR setting, by far, is shooting city nightscapes. This shot in Singapore was taken via HDR Level 6. |
Dynamic Range Optimization (covered extensively in the previous section) is a nice feature because it can make the most of one exposure; the drawback of it (as I’ll show shortly) is that it increases noise in the shadows – something that many people just don’t like.
So that’s one way to (virtually) increase dynamic range. The High Dynamic Range function provides a second, perhaps more time-honored way to solve the same problem.
First, some background. In the olden days (like ten years ago), whenever people wanted to get around the 8-stop range of digital sensors (shown in Figure 14-15), they would put their camera on a tripod, take several pictures, each 2 or 3 stops apart, and then merge them in their computer using programs like Photomatix or Photoshop’s Merge-to-HDR feature. An example of this using the old technique is shown in Figure 14-16.
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Figure 14-15: The HDR technique can capture much more brightness range as compared to taking just one shot. But take care that the brightness range of the scene you’re shooting falls within this expanded sensitivity! If not, an HDR shot will still not capture everything you see. |
But what if I told you it were now possible to take HDR images without a tripod, without Photoshop, and without any technical knowledge at all? The camera you now own can do this for you. To invoke it, put your camera to P, A, S, or M mode and then press MENU --> 
5 --> DRO / AUTO HDR --> HDR AUTO. Then point and shoot at a difficult scene. The camera will do the following:
Figure 14-16: High Dynamic Range imaging done the old way. The idea behind HDR is to take several different exposures, capturing all of the brights and darks that the scene has to offer (typically more dynamic range than a camera sensor can capture in a single shot), and then merging the images in your computer to make the image look a little more like the way you saw it. This is a relatively simple example -- the first three images were taken on a tripod, and bracketed 2 stops apart. The fourth one shows the output from Photoshop’s “Merge to HDR…” function. |
TIP: Unlike DRO mode, HDR mode is not invokable in RAW mode. So if you are in RAW or RAW+JPG, the camera won’t let you invoke HDR. And if you’re in HDR mode and then choose RAW or RAW+JPG, then camera will default to DRO mode until you return to .jpg mode. |
