Exposure Bracketing-Incease Dynamic Range

This week I will discuss Medium Dynamic Range (MDR). This is a way to decrease noise and increase detail by combining 3 exposures. Let us look at the following examples to see why you would want to do this.





As you can see there is a definite decrease in noise and increase contrast or detail. This is why this technique is a staple of all jewelry photography professionals. Here is how this technique works. You will need 3 exposures, preferably a range of -2,0,+2 or -3,0,+3. In my MDR example I used -3,0,+3.

You take your under exposed (-3) photo and make this your bottom layer and set the blending mode to Normal:



You take your middle or normal exposed (0) photo and make this your next layer or the layer over the under exposed (-3) layer and set the blending mode to Screen:



You take your over exposed (+3) photo and make this your top layer. Stack this on top of the -3 and 0 layers. You will make the blend mode for this layer Multiply:



Vola! And now you have my MDR example. This technique does not increase your workflow time significantly. Since, in the LDR workflow, you are taking multiple exposures to find the best single exposure and in the MDR you are taking 3 exposures, the working time is about the same.

As you can see from the results, one is better off taking 3 exposures for the MDR effect. For the same effort of trying to get a good single photo, you get the benefits of decreased noise and increased contrast.