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Outline

 Copal metal square shutter
 Lock-needle exposure automation
 Center-weighted metering circuit

Author

Ryuji Suzuki

Konica Autoreflex T, T1, T2

Autoreflex T series follows Konica's Auto Reflex (two words). T1 is sometimes informally used to designate T. T2 is a modified version of T, and the body actually indicates T instead of T2. T2 differs from T slightly and subtly in appearance.

Copal metal square shutter

The shutter is a prominent feature of this series. See A short history of Konica SLRs.

Lock-needle exposure automation

The metering circuit is shown below:

Let us follow the diagram from the left to the right. The three-contact switch is a red push switch for battery check, located on the base plate of the body. This switch often suffers from poor contact. It sometimes needs dozens of push-in workout to clean up, but more often, the material is corroded and more radical dissection is necessary. The two-contact power switch is located on the shooter's side of the body in T (T1) and on the collar of the shutter release shaft in T2. This switch is also prone to suffer from poor contact. The power switch on T2 usually needs nothing more than a few dozen times of working out.

CdS is a kind of photoresistor. There are two units fixed onto the pentaprism. However, each unit contains two separate cells, one is for center weighted metering, and another for average metering of the entire view. Therefore, four CdS photoresistors are indicated on the circuit schematic diagram.

Center-weighted metering circuit

Konica's center weighted meters tend to have the highest spot a little lower than the center in the landscape format. May it be a too much of guessing to say it was intended to read more proper value when shooting average landscape scenes including the sky as a half or a third of the scene?




Written 12 Dec 2001, Updated 21 June 2003