Having got started on this section I am now on a roll, particularly now that the weather has changed and you WANT to be out.
I’ve tried to find some really different scenes and challenge myself a bit with this exercise starting with the moon which was the subject of my last post. They haven’t all been easy and I haven’t always got what I expected, for example in my second scene. I was taken by some leaves from an indoor plant casting a shadow on the wall with the sunlight coming through the conservatory window so I decided to experiment with this light. I chose quite a difficult subject, a wine glass, and set it on a small, white, table top photography stand. I started off measuring from the lightest area of highlight in th glass.
This produced a shutter speed of 1/800 at f11, the highlight was correctly exposed but the rest of the image very under exposed as I would have expected. Measuring exposure from the darkest area of the shadow produces a shutter speed of 1/250 at f11. In this case the image was generally fairly well exposed expect for the highlights which were clipped quite extensively. The best result was produced with an exposure of 1/320 sec at f11 although I did need to tweak the brightness in Lightroom 4 to get something I was happy with. The dynamic range in this scene as only 4 stops which surprised me to some extent. I guess that although there were some very bright areas in the highlights, there weren’t really any very dark areas so there was not really that much contrast.
My next scene was a rose in the early morning light and again, there was not a huge amount of contrast in the scene. The brightest area gave me an exposure of 1/200 sec and the darkest shadow at the bottom a shutter speed of 1/100 sec, only 1 stop difference. Although the histogram showed that the former was slightly underexposed, I prefer that of the 2 shots.
Scene 4 was taken in Gloucester docks towards the end of the day as the sun was starting to sink. Again, although it is a brightly lit scene, there is not a huge amount of contrast in terms of lighting and there was very little difference when measuring exposure from the darkest and lightest parts of the scene, 1/20 at f14 and 1/30 at f14 respectively.
Finally I chose an old crane which sits in the docks. The sun was off this by the time I photographed it so the lighting was quite flat. The difference in the photographs was much more noticeable when I measured from the lightest and darkest areas although the range was only about 31/2 stops, 1/25 secs at f14 compared to
1/4 sec at f14. I think the difference here is that because the crane is predominantly black, the camera tried to compensate and over expose when I focused on the really dark area. The image here is in the middle of that range, 1/15 secs at f14.
One of the really basic things that I discovered whist doing this exercise is how to lock the exposure and re focus. Having not used stop metering before I had not needed to use it and that in itself has been valuable.
When I started this exercise I might have been guilty of exposing for the lightest area so that the highlights were not clipped as I thought it was easier to pull detail out of the shadow than blown out highlights. That might still often be the case but I do now realise that it depends entirely on the scene in question, for example I had to find a compromise in the wine glass scene otherwise the whole scene was too dark. I also now realise that brightness and contrast are two entirely different things, not only can you have a very bright scene with relatively little contrast, but the opposite also applies.