Saturday 5 July 2014

Mamiya 70mm f/2.8: Two Pianos


A while back I wrote about the Mamiya 80mm f/1.9, which was the Mamiya 645 system's big star lens. It was unusually fast for medium format and surprisingly affordable as well, albeit that the bokeh was quite rough.

The early 645 system had two other standard lenses. There was the 80mm f/2.8, which usually came with the camera, and the 70mm f/2.8, which was a specialised choice aimed at professional portrait and wedding photographers. Its gimmick, it's raison d'etre, was that it had a built-in leaf shutter.


Reala

Leaf shutters are blown across the stormy bay can synchronise with electronic flash at all speeds, which is important if you're shooting portraits in daylight and you want to use fill-flash. The 645 system ordinarily uses a focal plane shutter, which is mounted in the body of the camera. The most common type of focal plane shutter has multiple blades that sweep quickly over the sensor, and when people talk of focal plane shutters they're usually talking about this kind of shutter. Most modern cameras use this system, because focal plane shutters can fire at very high speeds, up to 1/8000 for the best. The downside is that they can only synchronise with electronic flash at 1/250 or so.

Older cameras synced at even lower speeds, and the focal plane shutter in my mid-70s Mamiya 645 1000S only syncs at 1/60. The absolute peak of 35mm film camera development topped out at around 1/300th (off the top of my head the Nikon F5, and one of the professional Minoltas from around that time, could reach 1/300th).

This isn't a problem if you never use flash, or if you use flash as your sole light source, if for example you're shooting in the studio. It does however become a major problem if you want to photograph a person outdoors in the sunlight, balancing flash and daylight. The archetypal outdoors daylight portrait looks something like this:

Ektachrome 160T / 35mm

The lovely Loren is lit from behind by the sun, so that her hair is lit up, just like the Bee Gees on the cover of their classic album Spirits Having Flown. That's the album they released just after Saturday Night Fever. It has "Tragedy" on it. The inside gatefold has a good example of slow-speed flash sync, which is another flash-related topic entirely. Suffice it to say that you can learn a lot about flash photography from studying album covers. And that's the 70mm f/2.8. Goodbye.

(rewind)

... lit from behind by the sun; it was a bright sunny day. I had the lens wide open in order to blur out the background, which meant that I was probably using 1/2000 or something similar. The problem is that without lighting up Loren's face, she would have been a dark silhouette. I needed to light her face. But how? One solution is to have an assistant hold a reflective panel just out of shot, but this is awkward if you're shooting a large group portrait, and difficult if you don't have a well-trained assistant.

Another alternative is to use bright constant light from a spotlight, but this requires a portable generator and a van and some power cables and clamps and a crew. And if you have access to a portable generator and a van, and some power cables and clamps, and a crew, why bother photographing people? You could probably make more money bundling pedestrians into the van, and threatening to have your crew clamp them to the generator unless they give you their bank details. You would be a modern-day pirate. A road pirate, with a van.




Provia again, for the first time

You can have a lot of fun with an electrical generator and clamps.

Alternatively you could use flash to fill in the shadows, but if your camera only synchronises with flash at 1/60 you can't shoot at 1/2000 any more. You have to shoot at 1/60, which means stopping down to f/16 or something horrible, or fiddling around with neutral density filters on the lens, at which point you're focusing and composing in semi-darkness.

For the shot of Loren I cheated and used technology. My old Canon 550EX has a high-speed flash sync setting that pulses the flash several times at the camera's sync speed. Most modern flash systems can do something similar. But before electronic trickery existed - I believe Olympus came up with the idea, in the 1980s - 1/250 was just about the best a photographer had. At that speed I would still have had to stop down, but only to f/4 or so, which is a lot better than f/16.


For the purposes of this post all of this information is basically irrelevant, because I only used the 645's focal plane shutter. In fact I didn't buy the 70mm f/2.8 for the shutter at all - I find that 80mm feels just slightly too narrow in 645, so I wanted a slightly wider normal lens. I don't plan on ever carrying the 70mm to a portrait shoot, it's too awkward and too wide.

Ektachrome EPP

Mine was cheap because the aperture blades are sticky. I have to toggle the stop-down lever a few times before they work, but in practice I shot most of the images in this post wide open, or I used the lens' MMU setting, which keeps the lens stopped down. The lens is nigh-on forty years old, and I imagine the lubricant has started to gum up. At this point a repair is uneconomical, and I'm wary of opening the lens in case I destroy the leaf shutter.


On an operational level the lens feels a bit of a kludge. It doesn't disable the 645's shutter, which fires as well as the leaf shutter. You have to set the 645 to 1/15 or similar, and when you press the shutter button the 645's shutter opens, then the leaf shutter opens and closes, and then the 645's shutter closes behind it. If you set the leaf shutter to "F" it remains open, and you can then use the focal plane shutter as you would normally.



The leaf shutter is essentially silent, but this doesn't help because the 645's shutter still fires, with a distinctive loud FLOP sound.

HP5

Ergonomically the 70mm's shutter cocking mechanism is as good as can be expected, with a pair of grips around the end of the lens. The procedure is laborious - and remarkably similar to the RB67, in that winding the film and cocking the shutter are separate actions - but I can imagine it becoming second nature. You wind the camera, twist the shutter, fire, wind the camera, twist the shutter, fire, repeat.


There's almost nothing on the internet about the 70mm f/2.8. Until the late 1980s it was the system's only leaf shutter lens, presumably intended for bride-and-groom shots. For the M645 Super, Mamiya introduced some other leaf shutter lenses - a 55mm f/2.8 (for group portraits), an 80mm f/2.8, and a 150mm f/3.8 (for head-and-shoulders). As far as I can tell there were no leaf shutter lenses for the autofocus 645AF, but the idea was reintroduced with the modern 645DF digital medium format system, which has a range of leaf shutter lenses, including a zoom.

Mariah Carey and Morrissey. I would pay money to see them do a duet.

Old 645 lenses can also be adapted for your modern digital camera, in which case the 70mm f/2.8 becomes a... well, it becomes a bulky 70mm f/2.8 with a built-in shutter that you can't use. Is that what you want? There are shift adapters, but do you want a 70mm shift lens? Do you? Hmm?


Provia 100

On an optical level I don't have a problem with the 70mm f/2.8. I used it purely as a standard 70mm. The shots on this page were almost all taken at f/2.8, using the 645's shutter. The bokeh seems smoother than that of the 80mm f/1.9, but still not particularly smooth; it has quite a bit of vignetting at f/2.8; if there's any CA, I couldn't see it; sharpness was just fine in the middle, still pretty good at the edges.


On an emotional level I still prefer using square format, as in this post about Mamiya's 6x6cm twin lens reflexes. 645 has the same 4:3 aspect ratio as Micro Four Thirds and old-fashioned televisions. and it feels a bit staid. I'm supposed to hold the opinion that aspect ratio is unimportant, and that what really matters is the brilliance of my compositions, but there's a reason Hollywood went with wider aspect ratios and stayed wide. My position is that a dramatic composition in a novel aspect ratio is more interesting than a dramatic composition in an over-familiar aspect ratio, and I'm sticking with that. Why is it more interesting? Because human beings are arbitrary, irrational creatures.

Many years from now, when people are sick of Instagram and widescreen - imagine being sick of Instagram! - 4:3 might well seem new; but I am living in the present. I write about the here and now, and individual people, the microscopic; not masses and not the future.