Besides creating the final image, HDR techniques can be interesting tools to get to an image one was aiming for when shooting.
Let's start with a normal single frame photo of the scene. This is the middle frame, i.e. the normal exposure image, of my HDR shot:
|Single shot @ -2/3 Ev|
It was a nice sunny day, contrasts running up pretty good! In such a situation, there is just so much one can do in post processing... saturation in both, the whites and the blacks. A picture essentially unusable. This shot is already 2/3 of a stop under-exposed, but still, the whites blow out. Of course, all the detail inside the depot is lost.
When using HDR as an intermediate tool, you will try to only compress the dynamic range and leave the rest essentially alone. The result will be a very very bad looking picture, but this is a good thing!
Have a look at the result of a 3 frames HDR (not cropped, just scaled down):
|3 frames HDR|
No, this was not a mistake, this was made that dull on purpose. Looks pretty odd to, like if there was fog. Fog would create very soft light, but the light is not soft at all, in fact, it is pretty hard, as you see from the sharpness of the shadows.
However, all of a sudden, in the lights, a tree is visible behind the building. At the same time the trusses inside the depot make an appearance too.
My picture shows the old tram depot of The Hague with ... old trams! Ideal to shoot an "old" photo.
Here, HDR can give me all the details, in inside the depot and outside it in bright sunlight.
Of course, conversion to black and white is the first step in the process.
The second step is to drop the highlights and raise the shadows, both to personal likings of course.
As a third step, the whites are driven up, just 'til the first regions saturate, the same with the blacks, of course downwards this time.
The second and third step is why HDR was used in the first place.
Optionally, noise reduction and sharpening could now be additional steps in such a workflow.
The result is a clinically clean black and white image. By far to crisp to be "old". To make a picture old, we need to add grain, as in the good old chemical photography times.
But, grain is not all, old lenses, I mean really old lenses, showed some distinct vignetting, which has to be added for the effect.
Actually, before vignetting, I cropped the photo a bit, as to fill the frame. I like the tracks, but not so much the bike stand. The bits of sky are not really adding much either.
The final image is that:
|Old tram depot The Hague|
A little bit of self-critique: I might have been a little heavy handed on the vignetting and the sepia color may be a little off. However, all in all, the image came out as envisaged.
- Olympus PEN E-PM2
- Olympus M.Zuiko 14-42mm II @ f/9 f=42mm
- ISO 200
- middel image: t=1s/200
- shot in RAW
- HDR: -3/0/+3 @ -2/3Ev