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This is not a full review of the Mamiya 645 AF, but rather a sneak preview. The purpose of sneak previews is to rush the latest information to the readers first-hand, enabling readers to make informed choices about your intended purchases. Thanks to special
arrangement, I was able to handle the M645AF before it is launched into
the open market. This sneak preview will offer readers some views and opinions
of the camera, so that you can decide if it is worth waiting for the camera
to hit the streets.
A new era On the first of March 1999, Mamiya announced the introduction of the Mamiya 645 AF System. The 645 medium format SLR was pioneered by Mamiya more than 25 years ago, and Mamiya has since dominated the 645 format with an excellent range of 645 cameras. Mamiya has been extremely successful with the Mamiya 645 Pro TTL camera system. With the introduction of the 645AF, there is no doubt that Mamiya hopes to step up its share of the 645 format market, The introduction of autofocusing to medium
format was first found in the Pentax 645AF. Subsequently, Contax jumped
into the AF bandwagon with its first medium format camera, the Contax 645.
Prior to these two cameras, AF was never associated with medium format
cameras. The two pioneering cameras have shown that it is possible to incorporate
AF into medium format cameras, and more importantly, there is a market
for AF medium format cameras. The introduction of the Mamiya 645 AF camera
will bring the number of AF medium format cameras to three.
Build and ergonomics We shall start with the looks and handling
of the camera.
Layout
Body
Finishing
Shutter mechanism
Others
In addition, the M645 features 2 dials for aperture and shutter setting adjustments. The front dial is operated by the index finger for adjusting shutter speeds (in 1/2 stops) and the back thumb dial controls the aperture. There is no aperture ring on the lens throat, so users of the original Mamiya 645 may have to get used to this system. However, it is pretty easy to pick up and you'll get used to the new system quickly. The lens change is ultra smooth, due to the absence of any mechanical linkages such as aperture stopdown levers. One drawback is the safety catches on the film magazine. The film magazine is locked in place by two catches, and it is a two-handed operation to change the film magazine. As a Hasselblad user who can change the magazine with a single catch, I find it unnecessarily complicated to operate two catches. But the added security of double-catches may be a plus for some users. At the end of the day, the Mamiya 645 AF
is evolutionary rather than revolutionary. Although it incorporates autofocusing
for the first time in the legandary M645 series, many components are built
upon the framework and technology well-proven on the manual M645 series.
Autofocus The MAMIYA 645 AF uses a TTL (through-the-lens), phase-difference-detection type auto-focus system. What this means is that the CCD sensors in the camera measures the difference and adjusts the focus until the difference in focus is eliminated, something akin to matching the lines in a split-field focusing screen. A built-in infrared beam is activated in situations of low contrast or low-light situations, assisting the AF to catch focus quickly. There is a choice between Single AF (focus priority) and Continuous AF (release priority), using the AF mode dial. The Mamiya 645AF uses the conventional
AF motor in the body to drive the focusing of the lens via a shaft. This
is the system used by Nikon for its non-AFS lenses. Unlike the much more
expensive Contax 645, the M645AF does not use ultrasonic motors, probably
to keep the costs down. The AF is not exactly the most silent that I've
heard, and Mamiya could have done a better job. The AF locks into focus
moderately quickly, but it is slower than a F90X. Perhaps a fair comparison
would be to say that it autofocuses like the Nikon F4. I think it is unreasonable
to compare medium format AF speed to that of a 35mm, but the M645 holds
up pretty well on its own though. It utilizes spot area focusing, so you
need to aim the center of the M645 AF at the object to focus, and hold
the shutter button half-way to lock focus. All this is easier done than
said, and it is quite a pleasure to use autofocus on a medium format camera.
Shutter The Mamiya 645AF utilizes a focal-plane shutter, which is electronically controlled for increased precision. In manual mode, the shutter is adjustable in 1/2 stops, from 30 seconds to 1/4000th second. This range is probably enough to satisfy almost all of your photographic needs. The shutter syncs at 1/125th sec. for flash-photography, which is only to be expected for a focal plane shutter. Frequent users of fill-in flash in sunlight might like to check out other leaf-shutter cameras for higher sync-speeds up to 1/500th sec, like the Mamiya RZ67 or Hasselblad 500-series. In AE mode, the shutter speeds and aperture
values are controlled automatically in 1/8 stop increments. A further control
exists in the form of exposure compensation of +/- 3 EV in 1/3 stops.
A mechanical T-setting (Time) also allows infinite lock-up of the
shutter without battery consumption, ideal for long exposure photography
(such as star-trail photography or astro-photography).
Metering The MAMIYA 645 AF has a total of three
metering modes: Center-weighted average, Spot, and Auto A-S (Variable ratio).
The Center-weighted and Spot metering are common to all the cameras, but
the Auto A-S mode requires a little explanation. This innovative metering
mode will analyze the image areas of brightness, and determine if the subject
is in contrasty lighting. If the meter detects high contrast lighting,
it will automatically switch to spot metering. Otherwise, the meter will
function using average metering in situations of average contrast. This
innovative metering mode was developed in the prism for Mamiya RZ cameras,
and implemented in the M645AF. The meter has a sensitivity of EV 1 to E'V
19, which gives is great for all but the darkest situations.
Lenses The Mamiya 645 AF uses the new Mamiya 645 AF mount, for which 6 new autofocus AF lenses are designed for. The lenses are as follows:
- 45mm f/2.8 AF
It is not known if Mamiya is going to produce more lenses yet, but my guess is that they certainly will. Although the current range of AF lenses is pretty complete, the new M645AF can do with more specialty lenses such as a macro lens and fast telephoto lenses. The 300mm lens incorporates Ultra Low Dispersion (ULD) glass to correct Iateral chromatic aberration, while the wide angles are designed with floating element mechanism, for enhanced sharpness from close-up to infinity. You can use the existing 22 manual focus
interchangeable lenses of the Mamiya 645 series for the new M645AF. The
manual lenses have focus confirmation capability and stopped-down AE
metering, enabling owners of the manual Mamiya 645 system to use them
on the new M645AF camera.
Magazines The Mamiya 645AF system has a total of 3 interchangeable backs: 120/220mm and Polaroid magazines. In addition, a digital back is being developed for the camera. The standard film magazine can be used with either the 120mm or 220mm film, simply by turning a dial on the magazine. There is no need to purchase different magazines for the two different format, which is a big plus. The magazines are fitted with ISO film dials and a small digital LCD display, making it very convenient to use the magazines with ther meter. Assuming that you set the ISO film speed correctly on the magazine, the meter will take note of the ISO speed whenever you swap magazines. This is accomplished through several contacts between the magazine and body. There are also spare inserts which you can purchase, allowing you to preload film for fast-paced shooting. The inserts are quite well designed, snapping in and out of the magazine smartly, with spring-loaded action. Like the Pentax 645AF, the Mamiya 645 allows
for data imprinting outside the image area of the film. I did not get the
chance to try the data imprinting, but according to the data sheet, it
is a pretty useful function. The data imprints can print the exposure mode,
aperture value, shutter speed value, exposure compensation and metering
mode. In addition, you can print the year/month/date/time and a identification
number too. The ID number is memorized by the "smart" body, so it will
continue where you left off if you decide to switch magazines and back
again later on. If you do not need the imprint function, you can simply
turn it off.
Flash metering Using Metz's SCA3000 module system, the
Mamiya 645AF can support TTL direct flash control system. This allows the
user to perform automated flash, which greatly speeds up shooting and reduces
the hassle of figuring out flash calculations. For those with a inherent
fear of flash photography, this feature will encourage you to use the flash
more often.
Price and availability The official price of the Mamiya 645 AF
has not been available yet, but a check with Cathay
Photo in Singapore revealed that it will cost around S$4000 (approx.
US$2424) for a complete set, depending very much on the strength of the
Japanese yen. The MAMIYA 645 AF will be available internationally by end
of October, and interested parties can ask for a online quotation from
Cathay Photo website.
For additional information: For additional information on the 645AF,
visit the Mamiya Forum at the Mamiya America Corporation website.
Specifications: Mamiya 645 AF Camera Type: 6 x 4.5
cm format, electronically controlled focal-plane shutter, TTL multiple
mode AE, AF single lens reflex
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