Archive | January 2007

Mamiya 6 vs. Fuji GA645


Part 1: Configuration and Basics

I chose to compare these two cameras because when I borrowed a Mamiya 6, I figured out that although they have different feature sets, they are aimed at the same types of applications.

Generalities: the Mamiya 6 MF is a 6×6 cm (55x55mm) camera that takes 12 shots on 120 film and 24 on 220 film.  It has manual focus, manual wind, and both manual and automatic exposure.  It has three available lenses, a 50mm, 75mm and 150mm, all of which fit in a collapsible lens mount.  Each lens has an electronically-timed leaf shutter and couples to the rangefinder in the camera.  The 6 MF with its 75mm f/3.5 lens runs about $900-1200 used.

The Fuji GA645 is a 6×4.5cm (55x42mm) camera that takes 15 shots on 120 or 30 shots on 220 film.  It comes in two variants, one with a 60mm f/4 lens (corrected for angle of view and film grain, it would be a 35mm f/2 on a 35mm camera) and one with a 45mm f/4 lens (like a 24mm on a 35mm camera).  It has autoloading; auto or manual zone focusing; program, aperture and manual exposure modes; a built-in data imprinter; and built in flash.   These sell used for $500-600.

Build quality: despite complaints about its “plastic feel” seen on the internet, the Mamiya is a pretty solid camera, quite a bit heavier than older-style 6×6 rangefinders like the Super Ikonta A.  It has a metal chassis and black plastic covers.  All markings are done in paint, including (incredibly) lens distance and aperture markings.  It feels like a very substantial camera, and there is no play in the lens. Focusing is smooth and solid.

The Fuji GA645, which is of almost identical size (except front to back) to the Mamiya, is much more lightweight.  Its covers are a dark grey and they are reasonably tough. The camera’s frame, lens barrel and focusing mechanism are metal.

Design influences:  The MamiyaÕs collapsing lens mount looks a lot like the one on a Retina IIc, right down to the internal bellows.  The grip and shutter release feel a lot like the one on a Nikon MD-4, albeit a tiny bit rounder. I don’t know where the huge shutter speed dial came from.

The Fuji GA645 came in on the same alien satellite that brought the Andromeda Strain to earth.  Actually, it appears to have been carved from a single block of soap. I have had this camera for four years, and I still could not tell you what it is supposed to look like.

Loading: On the M6, the pivoting pressure plate (rotates 90 degrees) sets the film plane and the counter for 120 or 220.  It also activates a window on the camera back which shows you what type of film you are using.  You pop out the spools by sliding two rectangular levers.  Film loads from left to right.  You line up the arrows on the paper backing with metal arrows in the film chamber by advancing the wind lever (one stroke per frame).  You then close the back and advance to frame 1.  Note: you cannot dry-fire a Mamiya 6 Ð if you want to play, you can wind discarded paper backing onto a 120 spool and use it that way.  Or you can pop the back open. After 12 frames with 120 or 24 with 220, the camera will keep winding.  The Mamiya is slightly harder to load, because it has a key-slot spool for the supply side Ð this provides extra tension on the film (supply side), apparently to prevent light leaks.

On the Fuji, you slide the pressure plate off its two pins and flip it over.  The camera then shows 120 or 220 on the LCD panel and sets the digital counter accordingly.  Loading is exceptionally simple.  Two red push buttons pop the spools.  Bring the backing over left to right, turn the control wheel to wind on, and as soon as it catches, close the back.  The camera detects the film start and winds to frame 1 accordingly.  There is no tensioning mechanism other than the spring on the supply spool, but I have had no light leaks from this arrangement. Film winds automatically with each exposure.  At the end of 15 or 30 exposures, the camera will wind up the film automatically (there is a button for doing that early, too).  You can set the camera to beep on the 14th or 28th frame to warn you that you will soon be out of film.

Viewfinder: The Mamiya 6 MF has an approximate 0.7x magnification and has aluminized (color-neutral) beamsplitters).  It features a rangefinder spot with vernier (hard) edges, a red LED shutter speed scale, and a warning light which comes on when the darkslide is closed or the camera is not cocked.  The 6 MF (as opposed to the 6) also has internal frame markings for 6×4.5 (horizontal) and 24x55mm panoramic.  These switch sizes depending on which lens you have mounted.  Framelines are parallax-corrected (position) but not field-corrected (image size). The Mamiya 6 viewfinder (except for the shape and the particular framelines) is identical to that on the Hexar RF.  The viewfinder is about the brightest, clearest I have seen on a medium-format rangefinder.  The shutter speed scale tends to get lost when you are shooting in bright light (just like it does on the Hexar).  This is a little problematic, since shading the VF affects the metering.  So the trick is to set the aperture for something you know will work if you have the camera on AE.  Camera reads exposure from the viewfinder.  Diopter correction is via supplemental lenses which push into the generous rubber eyecup. Like Leicas and Hexars, the Mamiya 6 finder is a little bit sensitive to eye position.

The Fuji GA645 carries forward the gold-beamsplitter rangefinder from the GS645S (“crash bar”) model and the GS645 folder.  It has framelines that shrink to show the parallax- and field-corrected view. I suspect that if this is like older Fujis, the framelines show 100% of the field at the closest focus and something like 85% at infinity.  It also has a central crosshairs for the AF system.  Across the bottom of the field is a segmented LED display which shows aperture (f/4 to f/22), shutter speed (slow to 1/700 sec), distance, flash (if enabled) and over/under indicators for manual metering.  The Fuji finder is not as bright, in part because the meter cell (as it does in other Fuji 645s) reads off the reflection on the front of the beamsplitter.  This makes the meter fairly sensitive to yellowish light and makes the field look bluish.  Diopters are standard Nikon FE/FM/FA size Ð not that you really need dioptric correction on an AF camera.

Both cameras have ample eye relief for glasses.

Shutter release: both cameras have both an electromagnetic shutter release and a standard cable release socket on the side. The Mamiya shutter release has far less travel (because it is a 2, not 3 stage switch).

Flash: both cameras have an X-synch hot shoe.  The Mamiya also has an X PC terminal on the back, right under the flash shoe.  The Fuji has a built-in pop-up flash that while wimpy, is pretty handy in a pinch. I am not sure if either camera would be fried by high-voltage synch, but I seem to remember sticking a Vivitar 283 on my Fuji at some point.

Lens: Aha!  Here is where the fun starts.  The Mamiya standard lens is a collapsible 75mm f/3.5 with 6 elements in 4 groups, multicoated.  The incorporated electronic leaf shutter has speeds to 1/500 sec.  Filter size is a massive 58mm (consider that a 28mm filter covers a RolleiflexÕs lens of equal size, coverage and speed).  This lens is the equivalent (horizontally) of a 45mm lens on a 35mm camera.  With a 1m minimum focus, this reaches 0.081x on film.  If you consider this lens on a 6×4.5 image, as you can with the optional mask, it is also a 45mm equivalent.

The Fuji has a 60mm f/4 lens with 7 elements in 6 groups, multicoated.  Maximum shutter speed is 1/400 sec, with 1/700 sec at f/11 and f/16.  Filter size is 52mm.  This lens is the equivalent of a 35mm lens on a 35mm camera.  With its 0.7m minimum focus, this lens reaches 0.093x, or 15% bigger than the Mamiya, despite the wide-angle lens.

Ok, time for an editorial.  With any interchangeable lens medium-format RF,  the highest-magnification lens there is is the normal lens.  Telephotos for these cameras never exceed the coverage of an 85mm lens for a 35mm camera, and even then they tend to focus at 2m or more at the closest.  So if you pick up a telephoto, you might consider it primarily a landscape lens. You might want to consider that apparent distortion picks up closer than about 1.5m, so you might consider enlargement as a better way of “zooming-in.”

Part 2: Operation

Collapsible lenses: both cameras feature collapsible lenses.  These make the cameras more compact, but even then it is a tight fit for the Fuji in a pocket.  The Mamiya is about 1 cm bigger, which makes it easier to fit in a bag but just about a total loss for a coat pocket.

Focusing: the Mamiya has a wonderful coupled rangefinder that is very bright and very clear.  That said, it is somewhat slow to focus because the grip on the focusing ring is quite small.  It does have a lot of snap, but when you are focusing on human eyes at the minimum focusing distance, you need to turn the camera 90 degrees to focus on an eyelid.  This is mainly a feature of the magnification, which has to be low enough to accommodate 50mm framelines.  The rangefinder does not work when the lens is collapsed.  In practice, the Mamiya is quick to focus and shoot.

The Fuji finder is not as bright and not as clear, but it does not need to be, since it is a framing aid only.  There are three focus modes with the Fuji: auto, manual and auto with hold.  Manual focus lets you set predetermined distances with which you can hyperfocal-focus (as I do 99% of the time).  The AF mechanism uses both active and passive elements and in more than 150 rolls of film now has missed maybe once.  The viewfinder display indicates distance and confirms where the camera is focused.  The Fuji is quick to shoot if you have some idea of what you are doing.  I think that the AF is most useful for low-light situations and it is pretty accurate.

Exposure: On the Mamiya, you set the exposure mode (AE or AE lock) or shutter speed via the large (yeah!) shutter speed dial.  You can also set film speed and exposure compensation (+/- 2 stops in 1/3-stop increments) via coaxial dials.  Aperture you set yourself on the lens.  There are over and under indicators for out of range, you match-diode by matching indicated shutter speed with the flashing one, but there is no exposure compensation warning.  In essence, if you can hack a 70s SLR or a Hexar RF, you can handle this one.

On the Fuji, the exposure mode (P, A or M) is set on the back of the camera.  In A, you turn the control wheel to set apeture and in M you press the Tv button down to change the shutter speed.  Exposure compensation (+/-2 stops, half-stop increments) is set by pressing the +/- button and turning the wheel.  There are up and down arrows in the viewfinder.  If the shutter is out of range, the speed flashes.  The EV compensation warning shows up on the LCD panel.  This takes some getting used to Ð unless  you are already an EOS owner.

Shooting: the Mamiya has no shutter lag and is very, very quiet (a lot more quiet than a Bessa-R).  Winding feels a little rougher than a Nikon F3, but it is similar in feel.  Single stroke advance is a welcome innovation for someone like me who is used to huge double-stroke Fujis.

The Fuji has some shutter lag if you have not already focused, and its winding mechanism and focus can be loud (although they are not obtrusive indoors).  The Fuji advances about 1 frame per second, single shot only.

Focusing: the Mamiya has interlocks to prevent you from focusing or shooting with the lens retracted or with the darkslide activated (the farbic internal darkslide is well-engineered not to be activated or opened by accident). The Fuji has no interlocks because when the lens is retracted, the camera is off, and it does not have a darkslide because it has a fixed lens.

Part 3: Format wars

One reviewer has called the Mamiya 6 MF’s multiformat finder “idotic,” “stupid,” and “cockamamie” and has decried the viewfinder as being full of “distracting blips.” His conclusion is that “Smart people just shoot the full 6×6 aperture and crop later.” This is something of an overreaction.

First, starting with the 6MF finder, the “blips” are small marks along the frame edges. They do not intrude into the frame by more than 1mm, viewed in the “virtual” size of the finder. These are actually quite useful, because the horizontal 6×4.5 frame defined in the viewfinder shows you what can be cropped into a 6×4.5 aspect (or more practicaly, an 8×10 print). While some people can apparently shoot a 6×6 frame and crop it perfectly down to 6×4.5, it helps to have some indication of how much scene fits into 6×4.5. So framelines are good.

Second, on the format adapters, I have to agree that any 6×4.5 mask that doesn’t increase the number of frames per roll (i.e., is not vertically-oriented) is not very useful. One aspect which should not be overlooked is that most 6×4.5 enlarging masks have the long side of the frame perpendicular to the length of the film. So you would have to use a 6×6 enlarging mask (or glass carrier) to print 6×4.5 negs turned out by the Mamiya 6 MF. Contrast this to the Rolleiflex T 16-frame adapter, which converted the Rolleiflex’s 6×6 frame to a 6×4.5, giving normally-oriented 6×4.5 negatives. The Rollei was a far more practical setup. Nor am I certain whether or not the 24×55 adapter is very useful. Although it has been pointed out that 35mm film, when shot in 55mm widths is just as expensive as MF film, there are a ton of 35mm films that do not come in medium-format (Kodachrome, Supra and Neopan 1600 being notable examples). The panoramic format does not look too terribly wide, but to each his own.

On the greater issue of 6×6 and 6×4.5 (Mamiya vs. Fuji), I think it is something of a wash.

If you anticipate that your final output will be rectangular, 6×4.5 has just as much usable film area as 6×6 and requires an equal amount of enlargement to reach a given size. Against this, the shorter lenses used on 6×4.5 cameras provide more depth of field. Film cost is something of a non-issue if you do black and white work, since TMY is $2/roll at B&H.

On the other hand, 6×6 is good if you like square compositions. You can, with a lot of discipline, compose so that it can be “cropped either way,” but in my experience, you will back up too far from the subject in an attempt to leave room for cropping. This means that the on-film image will actually be smaller than it would be on 6×4.5. Moreover, most subjects I have seen just don’t crop both ways. Head shots in square format can look really good.

Part 4: Optical Performance

Above is a shot taken with the Mamiya’s 75mm f/3.5 from the second floor of a parking deck across a street from Comerica Park in Detroit. Exposure was on Verichrome Pan, f/8 and 1/500 sec. Below is the tiny section of the negative that shows a batter, the catcher, and the umpire (visible as dots right above the center of the five statues). As a section at 4000 dpi brought up to 1:1 on screen, this is more than a 50x enlargement. Not too shabby, and you almost have to wonder if with a finer-grained film (is there one?), the Mamiya would be even better.



Part 5: Bear vs. Shark – Mamiya 6 vs. Fuji GA645

Ok, kids, this is what you’ve been waiting for. The $1200 Mamiya 6 vs. the lowly $450 Fuji GA645. The test shot is on Verichrome Pan 120, shot at the same mid-aperture (f/8), developed in Aculux 2 and scanned on a Sprintscan 120 with a glass carrier. The differences in comparison pictures are due to the different viewing angles of the lenses. The Mamiya 6 is the equivalent of a 42mm lens; the GA645 has the equivalent of a 37mm lens. Black point was set to the film base; white point was set to the imprint.


Above: Lower end of the tonal scale. Mamiya 6 (left); Fuji GA645 (right). No advantage either way – both cameras are resolving details as small as the film grain. The Mamiya has a slight edge in the stone seams.

Above: Highlights. Mamiya 6 (above); Fuji GA645 (below). Fuji has a slight edge in separating highlights, but it may well be that the Mamiya is giving marginally more exposure, putting the film over its shoulder (admittedly taking a lot of exposure to do that on VP).

Above: High-contrast object. Mamiya 6 (left); Fuji GA645 (right). No palpable advantage either way – the Mamiya looks more contrasty, but this may be an exposure difference (more) or even a higher magnification.

So what’s the call? Hard to say. It’s a dead heat between the two, and it may boil down solely to your personal preference in terms.

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Block diagrams of Canon RF lenses


Thanks to Mr. C.K. Soh