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11 User hints

11.0 Introduction

This section is for personal experiences, and any miscellaneous items not noted elsewhere.

11.1 Weight

The earlier models are heavy when compared to other 6x6 cm interchangeable lens cameras. However, comparing a typical 3-lens system shows a slightly different story:

Table of system weights, typical 3 lens system

Lens

YashicaMat

(non-metered)

Bronica SQA Hass.CF Mamiya 6 C33 C220 C330 C330s
50-60 - *590 *680 +335 360 360 360 360
75-90 (fixed) *490 *510 +250 365 365 365 365
150-180 - *865 *1075 +480 640 640 640 640
Body 1105 *1010 *990 +890 1810 1150 1465 *1340
Total 1105 *2955 *3255 +1955 3175 2515 2830 2705

Weights are in grams. This is only a rough comparison. There are differences in maximum apertures, and the focal lengths are not exact matches. However, it suggests that there is little practical difference between the reflex models for a similar kit. The Mamiya 6 is a rangefinder model, the Bronica SQA and Hasselblad CF are single lens reflexes, and the YashicaMat is a fixed 80mm TLR. All are 6x6 cm format. * Estimated weight from published data. + Manufacturer’s published data.

11.2 Lens caps

Rear lens caps are particularly hard to find, and substitutes even rarer. It may be worth contacting your national Mamiya representative directly, as there are some still available. The rear caps for the black series lenses are oblong with radiused ends. The inside of one end has a full circular rim that fits around a rear lens element. Two sizes are known:-

38.4mm diameter, 6mm deep (Long)

Fits 250mm, 180mm, and 135mm black series.

31mm diameter, 6mm deep (Standard)

Fits 105mm DS, 105mm non-DS, 80mm, 65mm, and 55mm black series. It will also fit the 65mm chrome and probably the other short chrome lenses.

It appears that the 35mm film cans used for Agfaortho 25 around 1992-94 will fit the 65mm and 105mm chrome lenses when cut down to around 15mm depth. Unfortunately this isn’t true of current Kodak and Ilford cans.

The ‘figure eight’ front caps don’t always fit well with filters in place. The older caps - pre-C33 - were metal, later ones were made of soft plastic. Standard clip fit-caps can be substituted, but they may need a flat sanded at a point on the circumference to provide clearance for the cap on the other lens. Pairs of caps can always be joined by a rigid bar or a cord.

Using stepping rings to standardise on 49mm filters usually means fitting new caps.

There are such things as body caps, though they are rare. This image of a “gif/bodycap.gif” body cap shows the general shape. This picture of the actual item is courtesy of Stefan Geyson. To get a normal sized template, make a pencil rubbing of the lens mount. The original caps have rims to locate the plate, but the clamp wire will suffice to hold a simple plate in place. The main thing to avoid when making a cap is fouling the shutter linkages.

11.3 Light traps

Most of the camera backs incorporate foam light proofing and film pressure pads. The pressure pad rests against the unexposed film spool, and acts as a friction mechanism to keep the film taut. The light trapping lies along the edges of the back.

This material does age, becoming less resilient, and eventually powdery. Local Mamiya parts suppliers may have suitable light trap material available.

Alternative materials:

Large areas can be replaced by a strip of hook and loop fastener (usually known by the trade name, Velcro (R)). The loop side is usually denser.

The thin light trapping strips are hard to replace. Moral: don’t damage them! A suggestion made to me recently was to use twisted or plaited black cotton.

The fine black foam used for computer mouse mats can also be used when suitable strips can be cut.

Foam intended for camera use can be obtained from Micro Tools (http://www.micro-tools.com/), though you may have to search for it. They have a big inventory.

11.4 Front Element Converters

Since this can be done, it seems worth a few words. But don’t expect miracles!

11.4.1 Video camera lens converters

There are a number of wide angle and telephoto front element converters available for use with video cameras. Typically these range from x0.42 and x0.5 at the wide end, to x1.5 or x2 at the long end. At least one company manufactures a reversible x0.5/x1.5 model. Those that are fitted with a 46mm thread are suitable for mounting on the later Mamiya lenses, either directly or via a 46-49mm stepping ring. It is possible to fit two of these devices simultaneously, but this may vary from lens model to model. If you go this route, expect to file a flat on one stepping ring to permit the other to screw down. It’s important that the stepping rings used are the same thickness.

Optical performance isn’t great. Not surprising, since they are intended for the more tolerant video optical train. The correction for aberrations is often poor, usually manifesting as barrel distortion with wide angle converters, and pin-cushion on the telephoto converters. But they are comparatively inexpensive, especially if you can locate a used pair.

However, if you would like a pseudo-super-wide lens then mounting a x0.5 on a 55mm will produce some dramatic effects. It isn’t quite the 27.5mm you might expect, but it does give a cropped circular image (corner vignetting). But don’t expect sharp results. You will need to experiment to determine the light loss. Typical values seem to be around half a stop for 0.5x or 1.5x attachments.

At the other end of the scale the aberrations seem better corrected. Adding a x1.5 to a 135, 180, or 250mm gives a nominal 200, 270, or 375mm lens. The trade off is whether the extra length gives better quality than enlarging the image from the prime lens.

11.4.2 35mm and digital format front element converters

These are made for fixed lens cameras, either fixed focal length or zooms. It seems that converters produced for 35mm cameras by the camera manufacturers are definitely better than the video converters. However these are generally too large to be mounted in pairs, which limits their usefulness.

11.4.3 General points on front element converters

Lens hoods and filter mounts are down to you. Though if you have a reversible 46mm converter you could mount 46mm filters reversed. And a 46mm filter ring can be glued to a suitable hood to make a ‘gender reversed’ version.

Note that the focus scales are completely wrong when using front element converters.

11.5 Other ‘Optics’

The TLR bodies make useful mounts for pinhole work. Cut a plate for the front of the camera, using a lens mount as a guide. Be sure to avoid fouling the moving linkages. Stout card will do, as will plastic, aluminium, or brass sheet. Drill a large hole in the centre of the taking lens mount, and paint the internal surfaces matt black. Your prepared pin-hole (there’s a lot of information on the web about this - try a search. You can also buy laser cut pinholes.), is taped over this aperture. An opaque flap over the pinhole is also useful as a lens cap. Black electrical tape will suffice.

The lens ‘Lock’ mechanism provides the equivalent of a darkslide and shutter. Since exposures are going to be at least 1 second, this poses no trouble in practice. You will also have to provide a ‘lens cap’ for the pinhole, because the shutter release is interlocked to the lock mechanism, and the film advance is interlocked to the shutter release.

For viewing, use the sports finder. With the bellows collapsed the standard 80mm finder is a good match. Racking the bellows out will give you a correspondingly smaller field of view, and a longer exposure. At maximum extension you get the pinhole approximately 135mm from the film; making the 135mm sportsfinder mask suitable. A slightly larger pinhole would be useful to give a constant pseudo f-number.

11.6 Front element exchanges

A number of people have reported success in exchanging the front element of the viewing and taking lenses of a pair when the taking lens has been damaged. However, each lens has matched elements and a simple exchange may not yield a decent result. A complete exchange of the optical components of the lens pair has a better chance of success provided the pair can be brought to common focus, which isn’t always possible.

The compiler of this document accepts no responsibility for the results should you attempt such an exchange.

11.7 Film advance slippage

There have been reports of uneven film advance. There are several possible causes; not all of which are serious.

Check that the camera back is fully closed and latched on both sides. Failing to do this can put uneven pressure on the take-up spool and cause the gears to slip.

Check that the camera is correctly set for 120/220. This usually manifests itself as a wrongly placed first frame.

Make sure that the shutter release is not depressed during film advance. This is especially insidious if a cable release is being used. Some cable releases do not always retract fully, and this can trigger the ‘short wind off’ feature (see sub-section 1.0.4 ). The effect can manifest itself as an extra rotation of the film advance crank, with very large frame spacing. Typically this could result in only 8 frames exposed with 120 film, while the remaining 4 are on the trailing backing paper.

Mixing spools from different manufacturers can cause difficulties. Some spools are fractionally narrower in film width than others and can cause extra friction when winding the film, particularly with 120. If you suspect this of happening, try using a take-up spool from the same film type. Since the number of film manufacturers is a lot smaller in 2015 than it was back in 1997, this issue may be (another) thing of the past.

If none of the above cure the problem, then you may have a fault with the film transport mechanism.

11.8 Flash Equipment

The flash connection (a standard PC synchronisation socket) is on the lens. This is discussed in Section 2.5 .

The equipment mentioned in the Mamiya TLR manuals is too old (and rare) to be worth discussing here.

The main requirement for using flash with these cameras is to ensure that you use a manual flash, or a system where the flash sensor does not rely on in-camera circuitry. This probably rules out flash guns dedicated to the latest auto-focus 35mm or digital equipment, but check the manual if you have such an item - it may also function on manual. There are a lot of older designs around that fit these criteria, and the vast majority of studio lighting is also suitable. Small hot-shoe only designs can be used with a hot-shoe to PC cord adapter.

Small flash guns can be mounted on the camera, or on a ‘L’ bracket, depending on the model, but these are quite close to the taking lens axis. This makes them useful for fill, but limited as the dominant light source. Tall, ‘hammerhead’ type gun, or a compact one mounted on a tall bracket will give better modelling. Don’t forget to allow for the size and shape of the finder you are using. You do not want to bang your head into it when using a WLF or chimney finder.

The shoe fitted to the C series always seems to come with the stop at the rear of the shoe. This is contrary to modern practice, and some guns may not fit without modification.

A small, low power compact gun, possibly in conjunction with an adjustable shoe adapter makes a good trigger for studio equipment and without the trip hazard of a synch lead. You can always tape a neutral density filter over the window to minimise any influence on the subject while retaining the trigger threshold.

Do remember to re-connect the flash lead when changing lenses…


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