Measuring exposure

Part A

The first part of this exercise required me to take several photographs which were intentionally under or over-exposed. I took them either one stop under or one stop over the average as per my exposure meter which was set to ‘partial’ metering. This setting gave quite a general average exposure of the scene (as opposed to say, ‘spot’ metering).

The object was to show that although the image we clearly under or over-exposed they could still look agreeable. I picked the images which most appealed to me from the selection and display them below. All photographs are straight from camera.

IMG_2190

1 stop over

IMG_2200

1 stop under

IMG_2198

1 stop over

IMG_2196

1 stop under

IMG_2192

1 stop under

It is of note that I have a fairly even spread of ‘over’ and ‘under’ (2 & 3 respectively) images. The underexposed images bring out more contrast especially in the clouds of the street scene and the colours of the windmills. What are the highlights of the green leaves of the trees in the overexposed version become well exposed here and give great contrast against the darker (underexposed) background.  The over exposure seems to emphasise the light surrounding the flowers and also the backlight appearing behind the green leaves. For the chalks the dark shadowed areas still create plenty of contrast but the colours come through the drop off of light at the top of the frame.

Part B

In this part I needed to measure the ‘best’ exposure and ‘bracket‘ around that. I was to bracket at half stops. That is 1 stop under, half-a-stop under, camera average (what the exposure meter advises me is the best exposure for the scene), half-a-stop over and a full stop over.

The results are below in a gallery, please click on the gallery to enlarge the images. Will the ‘correct’ exposure be the one I chose from each sequence or will it be one of the other exposures? If it is not the ‘correct’ average exposure then why would I prefer it?

Oev (exposure value) is the suggested ideal exposure that the exposure meter gives me. I think most of the exposures are acceptable with maybe the exception of -1ev (1 stop under exposed). I prefer +.5ev (half-a-stop over exposed). It pushes the background a little lighter which reduces the effect of the blemishes on the wall behind. It also lifts the whites of the china teapot.

Again I prefer the +.5ev exposure here (and could be pushed towards +1ev). Although the underexposed and Oev versions have bluer sky I really enjoy the backlight on the green leaves. The sun was quite high in the sky and so the top of the leaves were fully exposed to the bright light. For me all the exposures here are acceptable on some level.

This is the only image of the series where my preference is for the Oev version. I suspect this is because this is the least dynamic of the shots and contains very neutral colours. It gives the best balance between contrast and exposure (as one would expect form taking the camera average). All exposures are acceptable although +1ev looks a little too overexposed possibly.

Given my penchant for urban decay I naturally gravitate towards underexposure for this image, my favourite being -1ev. This gives the dark brooding feel and contrast that I want from the image. Possibly -.5ev is technically the better image but I am being subjective in this exercise. All exposures are acceptable although I feel +1ev is really starting to lose definition.

This is the least satisfactory image of the series and I had trouble picking out a preference. In the end I would pick pout -.5ev as there is more detail in the petals whereas this is lost at just half-a-stop higher (Oev). The underexposure also darkens the background somewhat pushing the flower to the fore.

In summary, I find myself choosing anything but the camera average, which leads me to think that I need to think harder about my exposure before I start.

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