James's Light Meter Collection: Spiratone (Sedic) MA-5 Expotrol Meter
Spiratone Expotrol MA-5 meter Japan
Maker: Spiratone (in USA; Sedic in Japan)
Model: Expotrol MA-5
Circa: 1968
Price (new): $99.95
Battery: tbd
Cell type: CdS
Measure type: 3D incident, reflected and spot with attachments
Spiratone Expotrol Ad


Modern Photography's Modern Test (November 1967)

With more and more serious photographers turning to built-in or through-lens metering systems, a seperate hand-held meter trying to holds its own today must do more.

Specialization is the key. We now have limited area meters, spot meters and meters with attachments.

Probably no other meter living or dead offer the number of possible functions provided by the Spiratone Expotrol (known as the Sedic in Japan). The design is unique and the list of attachments allows you to buy seperately (which costs more), in groups, or all in one (the most economical way), as your budget or needs require.

When all units are resting in their blue foam attache case cutouts the effect of so much precision and glitter is overwhelming in a full-color, Cinemascope sort of way. But now let's trot each item out for a closer look. Then we'll check to see how well they operate.

The basic 3-in. diameter meter has a long needle plus overlarge dual scale on one side, controls plus CdS window on the other and the expsoure scales around the inch-thick rim. You select high- or low-level scale by moving a good-sized lever on the back of the meter. You hold the meter up to take a reading and push in a lock button on the meter back to lock the needle in place. The scale has a low range from 1 to 10 and a high range from 9 to 18. This is a clever and useful design, since the repetition of part of the scale between high and low prevents users from the frustrations of readings in between.

You turn the outer rim of the meter until a short white marker lines up with the number on the meter scale. Speed and aperture combinations can then be read on the outer dial.

The meter itself is not extraordinary. The 90° coverage may be very useful for anyone attempting to obtain an integrated reading for his extrawide lens, but close-up readings will have to be taken to get good results for any other focal lengths. The ASA index scale on the outer rim is not clickstopped and may move when using the rim calculator. Because the meter scale must also be adjusted for the various accessories (all of which are marked for the proper adjustment), a separate scale reading must be set in a window on the outside of the rim. This too is not clickstopped and may move. It's advisable to check both ASA and accessory scale windows.

The Expotrol alone is quite sensitive, reading down to 1 sec at ƒ/1.4 with a film having an ASA index of 400. In addition, a check with our P-803 Aerotronic meter tester indicated that the Expotrol maintained accuracy to within ½ ƒ/stop over the entire range when compared to a known light source.

Numerals are very large and legible and well spaced. Locating the needle lock button on the back of the meter by feel requires some practice in sorting out the controls. To unlock the button, you must press downward on a small concentric lever near the button. The high-low switch has click positions for "battery check" and "off."

There is no between-number scale markings on the meter dial, although such markings do occur on both the shutter speed and aperture rings. You can interpolate between scale numbers, however, and then set the pointer between the numbers on the dial scale.

The ASA dial thankfully has easy-to-see large numeerals for all the current odd-ball ASA indexes—64, 125, 160, as well as the usual numerals.

The $39.95 meter and accessory assortment provides you with the $5 incident light measuring dome and 50° "normal" lense attachment ($4), as well as a leather case ($6).

Incident light measuring enthusiasts will find that the dome is far larger than any of the incident attachments of other reflecting meters. It gathers incident light more effectively and covers the same range as the meter alone, with the same good accuracy. Like all the attachments, it bayonets securely over the CdS cell window.

Many camera owners will want to use the 50° attachment as an all-purpose accessory. The 50° attachment worked as accurately as the meter alone, although the useful low range was abbreviated slightly to ¼ sec. at ƒ/1.4.

The truly interesting accessories are in the $99.95 kit. First, let's take a look at the wonder wheel—the turret disc which bayonets in front of the CdS cell and provides readings of 7.5°, 11.5° and 17°, approximately the covering angles of 300, 200 and 135mm lenses on a 35mm camera ($25). For each angle there is a separate optical finder of a type not seen here since the old Voightländer Contour and the finder the Kalart 3½ x 4¼ press camera. If you can keep one eye closed and look through the finger itself, you see inky blackness with a bright circle. However, by keeping both eyes open, the bright circle (representing the field coverage) appears to be projected right over the view. Each field is clearly marked int he finger. Readings could be made down to 1/15 at ƒ/1.4.

The turret finder has an adjustable eyepiece and can be switched from one angle of coverage to another with a quick flip of the finger. Since you can't see the scale while using the finder, you must of course sight your subject, press in the needle lock, and then examine your reading.

The turret finder can be used as a substitute for a through-lens integrating meter system with the three telephoto lengths. Our tests indicated that its through-tens integrated meter when used under average lighting conditions and even for bright objects in the middle of a darker field—a stage presentation or sporting event, for instance. However, it is not as accurate as a though-lens meter when measuring dark areas surrounding light ones, such as a shadow area in a distant doorway. Here a close-up reading with the Expotrol would be advisable.

The most selective accessory is the spot attachment with prism reflex focusing eyepiece ($30) which measures a 3° field. This device has another type of viewing system. You look downward into a reflex finder where a semi-silvered prism reveals the field of view with a superimposed 3° circle. Readings down to ƒ/1.4 at 1/30 sec. are possible. Our tests indicated that it could measure with excellent accuracy to ½ ƒ/stop in average areas in dark surroundings, but was less successful with the dark areas with bright surroundings. Here again, a closer reading would be needed for a check.

The TTL attachment is simply a plain metal ring with a rubber surface which can be pressed against an SLR eyepiece, or view camera ground glass.

Obtaining accurate readings through an SLR viewfinder remains a questionable technique as far as constant accuracy is concerned. However, for view camera use, the TTL attachment is splendid, allowing you to take precise measurements from whatever part of the ground-glass image you wish. There isn't any room for your finger between ground glass and meter, so the needle lock cannot be pressed in, but since you can see the needle easily, there's really no need to lock it up.

Last available item is the hard grip ($8), which threads into a socket at the rear of the meter. A rocker lever on the grip allows you to lock the needle momentarily with slight pressure or push it all the way for full lock. It's the handiest way to use the Expotrol.

In our opinion, purchase of the meter alone or with the basic $39.95 kit makes little sense. The most important and useful items are available in the $99.95 kit {which if bought separately would cost more than $130).

For the usual price of a spot meter alone, you then have a versatile metering system capable of many kinds of exposure measurement.

Admittedly, for $100 you can get a single spot meter which is more convenient than the Expotrol, or a more convenient incident light measuring meter or reflected light meter. But this bulky package of three meters could easily run over $250. There is no meter of all trades.—THE END

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