Full Title: Is HDRi relevant as a photographic technique or mearly a special effect process?
I have chosen not to give my reasons for discussing this subject and I believe that for most people interested the reasons will be obvious. This is just a demonstration of why I use HDRi technology as "one of the tools in my photographic toolbox"
I have deliberately directed this at people who understand the photographic process and a little about HDRi images. I am not trying to exclude others from the concepts involved here and am very willing to answer any questions from anyone of any age or ability in order to help explain the subject matter. THANKS.
This image was created from the 3 files which I have overlayed it with.
I was returning from a shoot back to the car and on the walk I saw an angle through the trees of Corfe Castle which I liked. I pulled my camera from my backpack and strapped it on to my tripod.
I realised due to the "against the sky" angle of the subject that I would end up with a silhouette image rather than what my eyes could see which was a subdued castle against a gorgeous sky.
I had 2 options if I wanted to create the image as I saw it rather than the silhouette my camera would record.
1. I could use a graduated filter over the lens which would help to hold back the sky so I could expose the foreground and castle a little better.
2. I could shoot multiple frames at varying shutterspeeds so as to cover the Exposure Range presented in the scene and then create an HDR image during processing.
If I had used the filter technique I would have been faced with a problem: As well as holding back the sky, which I wanted to, the filter would also have held back the top of the castle, which I didn't want.
I would have ended up with an image similar to the way my eyes could see the scene but with a distinct graduated light effect from the top to the bottom of the castle. This would have been acceptible at best but very obvious to me, ruining the picture at worst.
So I opted for the HDRi technique:
I framed the castle as I wanted it through the viewfinder and locked my tripod in place. I then set the lens aperture to F8.0. Then I exposed the first of 3 frames at 1/125 sec - about 1.5 stops below the metering on the camera. I shifted the shutter speed (whilst keeping the aperture locked at F8.0) to 1/50 sec (just over a stop higher than the first frame) and made another exposure. Then went up to 1/25 sec (a stop higher) and made a final exposure.
I now had the 3 images which you can see around the outside of the picture above.
The 1/125 shot is too dark as an image on it's own. The 1/50 shot is just too pale overall. The 1/25 shot is too bright with the sky burnt right out.
If I was to have used any of these images then either I would have to suffer a silhouete as my final image or lose the gorgeous sky. If I had used the middle exposure I could have got away with the shot as far as exposure goes but even with some lengthy processing it would have looked flat and lacking in contrast with the sky pushing the limits of brightness and parts of the castle showing no
shadow detail at all.
So I took my 3 RAW exposures into Photomatix Pro (HDR sofware) and allowed it to combine the three 12bit images into a single 36bit file. This is one image which contains all of the combined shadow and highlight detail from all 3 exposures. As it is this image is useless. It contains far too much detail to be viewed on a screen or in print which both only support an 8bit tonal range.
The next step was to "Tonemap" this huge file into an image which is able to be viewed as a photograph. This too was done in Photomatix Pro.
The result is the image above. You can clearly see the detail and colour in the sky, the detail on the castle and even some colour in the tops of the trees at the bottom. This is, more or less
how the scene appeared to my eyes at the time. To me it doesn't have the tell tale fake and flat look which gives HDRi a bad name. To me it looks real and more importantly the way I wanted it to.
So - Is HDRi relevant as a photographic technique or mearly a special effect process?
The answer is up to to you. My mind has been made up for a long time.
PLEASE TAKE A LOOK AT "Corfe Castle" [link]
in my gallery. It is the final image from this set. I have converted it to black and white which was my original idea for this scene. I hope you like it.