Due to a very nice post by Harry Briels, I have decided to share my current knowledge of DRO+ with the rest of the bunch. I am leaving out standard DRO because it has been documented to only make levels and contrast adjustments to the scene, something that can basically be duplicated in photoshop.

The same cannot be said for DRO+. While some may think they can do the exact type of duplication in Photoshop or other Software programs, they would be wrong to say they can get the exact results. The reason? DRO+ uses a separate internal processor (read on), and processing to get this result. If this topic interests you, and if you have any conclusive evidence to add to this, please feel free to add to this forum topic. But please, only add conclusive evidence that can be backed up by statements from Apical or Sony only. I see a lot of misunderstanding about DRO+ on the net, and users from other brands of cameras confusing DRO with DRO+ (two totally different animals).

Dissecting DRO(+) isn't as easy as, I guess, it should be. Sony gives very little information about DRO(+) in general. But, I have compiled some information that is available out there, if you dig it up.

I have contacted the people at Apical, who Sony licenses the technology from. They state that Sony takes their stuff, then tweaks their own adjustments to the technology from there. They make it, Sony tweaks it to their specifications.

Therefore, I can only get so much information from Apical regarding the subject, they seem to go much further in explaining the technology than Sony does, but they can only go so far since the rest is under the hood at Sony.

That said, here is what I understand so far (and just skip the portions you already know):

So that leaves us to testing DRO+ and publishing the findings. DRO+ is kind of complicated in how it works. With each scene, the Apical processor that sits beside the Bionz processor, is calibrated to do certain levels of adjustments based on the information it receives about the scene from the Bionz processor. It then runs through Sony's software and additional and final adjustments are made to the scene (both processors work together).

Lots of blank spots there in the knowledge of what is specifically being done. I mean, what is going on with the communication of the two processors? What I know is this:

DRO+ is designed to mimic the scene to more closely resemble what the human eye sees in dynamic range, in increments of proprietary strength of 1-5 in DRO+ mode. So what strength is exact to the human eye? Well that depends on the scene, and the overall level of Dynamic range it has! (I know... grrr!)

When shadows levels are brought up, more noise is introduced in those shadow regions. The level of noise and the final outcome is determined by a basic equation:

The total range of the scene
X level of DRO adjustment
X the level of ISO
X unknown Sony processing factors and Apical processing factors.

Great, hah?

So, since every scene is different, there are literally a myriad of different results :) especially when you calculate all the programming that is being done in the camera to get "human eye results".

What the heck does that mean anyways? Well, as far as I understand it (and stay with me here), the dynamic range of a scene the human eye sees (about 14 stops of exposure total) is obtained after about 4 minutes of internal chemical adjustments, and our initial range in a scene is 6-7 stops of light.

Apical has studied the total contrast ratio of the eye about 100,000:1 after a 4 second adjustment, initial 10,000:1, the level of dynamic range (about 14 stops), the colors the eye sees, and much much more. To date, they have more research about this subject for a photographic application than any other company that I know of.

We are privy to the best of that knowledge with the use of the A700, nobody else has it in the same fashion, or to the degree it has been applied to the A700 (Sony has huevos for introducing it into such a camera).

So.

All that aside, here's what I know so far basically:

The higher the ISO and DRO+ level you use, generally the more noise that is introduced into the shadow regions. I have done a simple test to confirm that much, and it is definitely true, and so have others (DPR tackled it too, good for them).

So as a photographer you have to make a decision. How much dynamic range is in the scene before me, and what level of DRO+ should I use to get the desired effect?

Obvious I know. So, keeping in mind the equation I laid out, and experimenting, you should be able to get a better understanding of what DRO+ does consistently (and it is consistent in it's complex equation, thank goodness) and make a decision on what level of DRO+ you should use.

Since DRO+ evaluates 4,000 areas of the total scene (and from what I have read also is capable of adjusting the levels of ISO in each pixel)and then processes what it "sees" the end result looks very much natural, as long as you nail the "DRO+ exposure".

Since photography is creative, I would not tell a photographer how much DRO+ to add to a scene, the photographer should already have the scene and end result mapped out in his mind (per one of Ansel Adams 10 commandments that I believe in).

I suggest doing a tripod test on a bright sunny day. Set your camera up, focus it on a scene, turn off AF. Make sure you take the shots in manual mode so the camera doesn't make any further adjustments when you make the following changes:

Take a series of shots a the lowest ISO level in the A700, ISO 100. Take five shots of that scene increasing the DRO+ value 1 step each scene. Then repeat that process at ISO 400, then again at ISO 800.

View your results, you might be surprised! Then try to pick the best pic out of the 3 series that truly matched what your eyes saw. At least then, you will have a starting point and a basic understanding thru results of what DRO+ is doing. Try the same test on cloudy days, night scenes, and any other conditions you would want to use DRO+ in. Use DRO+ bracketing too! It works.

I will go into DRO+ more as more information comes to me, I am in touch with Apical, but that isn't helping much. I need to talk with someone at Sony for more "Technical" inside information, and well that is next to impossible to get any real answers out of them. They may not want to tell the competition it's secrets, and to that stance, I would wholeheartedly have to agree with Sony on that. I wouldn't give them an edge either.

Hope this was a little bit helpful. :)

-Carl