I’ve been asked lately about the HDRs that I do and how I do them, instead of responding to the individual e-mails and comments I figured I’d do a series of posts over time and this is the first instalment. First off, let’s be honest over here: I’m not a professional and I don’t think I’m that good; I do think that I’ve improved a lot over time though I do appreciate all the kind comments so with all the humility I figured I’d share the knowledge. But as the saying goes: “Give a man a fish; you have fed him for today. Teach a man to fish; and you have fed him for a lifetime”, I don’t want this to be a recipe type of “knowledge sharing” so its only appropriate to start with why use the technique to begin with.
First you must realize that the human eye is an amazing “sensor” compared to any other camera made to man. The dynamic range (area going from really bright to really dark) covered by the human eye is almost twice of that of a top of the line camera sensor. The image above is the complete HDR which is more representative of what it really looked like that day; I remember the green grass, the blue skies, the orange sunset thats what my eyes were seeing. If you get your camera out, set the aperture and shutter speed to a “correct” exposure chances are you going to get something like below:
The sky is pretty much completely blown out, the details in the trees are completely gone but I do remember the clouds and I do remember the flowers. The histogram of 0 EV bias shows that we have blown out areas (right side) and clipping (left side) :
This is one of the best times to apply the HDR technique to capture the scene and the whole idea is to take multiple exposures that will capture the whole dynamic range of the scene. Over time you’ll build the experience to determine how many exposures you need and what range to capture in the meantime just use the histogram, its there for a reason The idea is not to have anything blown out in the most underexposed image and not to have any clipping in the most overexposed image.
I will get into more of the technicals in a future post if people find this helpful but I think its key that you understand why HDR is needed so you know when to use it. Which leads me to my 2 lessons that I learned as a beginner and I’m sharing with anyone starting out with HDR:
1- If you want to do HDR Photography don’t forget the photography piece which means composition… its all about that, HDR is just a technique.
2- Not everything needs to be an HDR, and I think specially if there isn’t that much variance in the dynamic range or texture.
For the image above I had to take 6 exposures from -3 EV to +2 EV and I took them at 1 EV interval. Here is a slideshow of the brackets, unfortunately I’m not sure how to sort them but they go in the following order: 0,+1,+2,-1,-2,-3 EV
I hope you found this helpful, if you follow this blog regularly you know I don’t write more than a few sentences a day so this was quite a stretch for me