Experiment 1
Home Computer Camera Lab Colour Space Post-Processing Tutorials WoW Albums Waffle Index



This page and others list further experiments and notes

Well I never

During testing I had two strange occurrences which I will record to remind me never to trust the new cameras without checking exposures as they are taken.

I was taking a grey card, on a tripod with the Coolpix P7000 under constant lighting and got these exposures in Aperture mode for the same f/5.6 within seconds of each other.

I was checking variation in lenses using a fixed aperture of f/8 with the D700 and the 2 inner images are from my wide angle lens.  I thought this must mean that the diaphragm is sticky and not closing down quick enough.

On further exhaustive checks, including rapid bursts, there was no change in exposure over the entire Aperture and Zoom range!

Stained Glass Window and Zones

The Spot metering of highlight and shadow are shown in this cropped composite image as well as the Matrix metering (that was heavily influenced by the wall area).

A range of 6ev, assuming the spot metering was correct. 

The D700 should be able to take this dynamic range in a single shot, but as the 400% ev 10 insert images shows, this was not going to be possible for jpg images to capture good detail at both ends.

The 'highlight' exposure can be ev10 as we can capture detail for 2 more EVs.

The shadow detail can be easily captured by curving a +2ev exposure.

So the minimum is 3 brackets of +/- 1ev centred on ev 9 (8-10 ev).

But for safety a 5 bracket on ev 8 (6 - 10 ev) was taken to ensure sufficient colour and shadow detail was obtained.

These set of exposures then allowed me to construct 2 different renditions of the window, depending on whether I wanted the stone work to be visible.  One could also have the dark window within the light stone work, if the glass rather than the whole image was important to emphasise.

I had a comment from Russell Cottrell on this photo, which says it from a different (more zone-ish?) view-point...

"it would have made more sense to me to say that at the given exposure (ev8), the dark area (ev6) fell on zone III, and the light area (ev12) on zone IX.
Bracketing, at the ev10 exposure, the light area came down to zone VII, which is much more manageable."


I've added a Zone Ruler to the Colour Watcher which should help one learn - not sure how useful it is in post-processing.