Readers Write: TZ7 2007 vs TZ7 2010? Let Me Explain ...

After the Panasonic TZ7 returned to the face-off earlier this week under the 2010 test procedure, a confused reader contacted us wondering which TZ7 test was the right one. Well, actually, both of them are! Let me explain ...

Hello, In your digital camera face-off, the Panasonic TZ7 appears twice and looks to have different results in the same tests. Which entry is the most reliable? Thanks in advance.

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Both entries for the TZ7 are reliable. When we have an inaccurate test, which sometimes happens if a camera's damaged in transit or has a technical fault, for example, we delete the incorrect test and replace it with a new one. In other words, a given camera will only ever feature once in the face-off, unless we intentionally create a second or even third entry.

Here then, there's a very good reason why the Panasonic TZ7 appears twice the face-off.

As I mentioned earlier this week, when we moved offices at the beginning of the year, we had to build a new camera testing lab. We therefore took the opportunity to update our test scene, as the old one was no longer sufficient to clearly highlight picture defects in the latest generations of cameras. As well as these intentional updates, the layout of the lab also inevitably changed, notably the lighting.

In the face-off, the Panasonic DMC-TZ7 test is useful to compare the TZ7 with other models tested between 2007 and 2009, whereas the Panasonic TZ7 (2010 Test Procedure) is useful for comparing it with any camera we've tested since the beginning of the year.

The only reason you might want to compare the TZ7 2007 Test Procedure with the TZ7 2010 Test Procedure is to see how the test procedure has changed. Even tests that look very similar, like the stabilisation test ('Barbie: Full-Size without Flash') have, in fact, changed. If you look at the shadows on Barbie's face or under her hands, in the older test, you'll notice the effect of a relatively homogeneous neon lighting coming from the back of the room, whereas in the new test, the lighting has changed to vertical spotlights spread over the whole ceiling of the lab and a halogen light pointing directly at Barbie from the side. You can therefore see Barbie's shadow falling to the right of her head in the new test.

So why did we change the lighting? Well, we wanted the lighting in the new lab to be continuous. Neon lights switch on and off around 50 times per second, which can disrupt certain cameras' light-metering abilities, making it difficult for them to select the correct white balance and exposure settings. With the new lighting, however, we have a new problem: overexposure, as the new set-up seems to make some cameras try to effectively capture both the back background wall and the foreground, which in turn makes Barbie's face look overexposed. This means that the results of the new tests can't be directly compared with the old tests, even though if some tests look very similar.

We'll be testing more older cameras with the new test procedure to give you more points of reference between our old and new systems. We've even dug out a Canon EOS 300D, which we first tested not under the 2007 procedure, but in our original 2005 test lab!


> Panasonic's TZ7 Returns to the Face-Off

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