TechSupport
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Flash adapter problem
Q I have a Nikon D90 and a Metz MZ 1 flash unit on the flash; I also use a Nikon adapter 32002. The problem is the flash and camera are not working together. What am I doing wrong? I’ve put the camera on auto mode and set the flash to easy mode, but to no avail. It just overexposes. Help! Pat Sexton
A I’m having trouble researching your problem based on the supplied information. If you can provide more precise details of the flash unit model name and the adapter I would be delighted to help. Metz model names and numbers are confusing at the best of times, but so far I have been unable to identify an MZ-1 model that pairs with a 32002 adapter. The Metz SCA adapter designed to work with your Nikon D90 is the 3402 model. ‘3002’ refers to the range of adapters, of which the 3402 is a member. There is a 3202 SCA adapter, but this is for Olympus cameras and would definitely not work properly with your D90. If it transpires that you have a ‘3202’ adapter, you could try to find a 3402 adapter. But frankly this would almost certainly not be cost- effective compared to buying a new, much more modern, inexpensive dedicated flash of similar power from Nissin, Yongnuo or other brands.
Precision of zoom lens focal lens markings
Q I have used a variety of brands of cameras and lenses over the years. I've found that what the focal length marking on a zoom lens suggests to be the field of view can be surprisingly different compared to another lens set to the same focal length and, indeed, to a prime lens of the same focal length. I know that fields of view and sensor/ film frame size are interrelated, so my observations are with the same frame size and the same camera. Is this just slapdash engineering of zooms or is there a more eloquent explanation? Henry Elsworth
A Yes, you are observing a phenomenon with zoom lenses called ‘breathing’. In fact, breathing can also be observed with primes. Lens ‘breathing’ is a trait exhibited to a greater or lesser degree by the optical design of a lens. A perfect pin-hole camera, which is entirely theoretical, doesn’t need to focus – everything from close-up to infinity can be regarded as in focus. With real-life camera lenses that need to focus at different distances, the field of view can change slightly according to the distance focused. The optical- design compromises with zoom lenses exacerbates this trait in varying degrees. Some zoom-lens designs minimise breathing very effectively over the focal length zoom range, while others don’t. Breathing is a particularly unwelcome characteristic for videographers as the symptom is much more noticeable than with still photography. You will find that both zoom and prime lenses are closest to their marked focal lengths when focused to infinity.