Deciphering the white 4-letter code on OM equipment

I noticed that many lenses, cameras and accessories of the Olympus OM

line have some white four letter "codes"; e.g. on the back of lenses,

in the battery compartment of flashes, in the film compartment on

cameras. Based on a comparison of these codes with the serial numbers

and putative production dates (e.g. for lenses which were introduced

after 1983), I interpret a code like "TNDA" as follows: letter one and

two code for the production plant, the third letter stands for the

production year with 1981 arbitrarily set as 1981 (i.e., C=1983,

D=1984, ... V=2002), and the forth letter indicates the production

month (1=Jan, ...9=Sept, A=Oct, B=Nov, C=Dec). I have not found any

A's or B's in 3rd position indicating that this code was introduced in

1983.

 

I would now like to know to which plant the first two letters refer.

Based on the large number of items baring a TNxx code, and knowing

that Olympus opened its Tatsuno plant end of 1981 which -for that

time- was highly automated, I think it is safe to think that "TNxx"

stands for Tatsuno. In a shareholders report, I found that Olympus had

the following plants in 2001: Ina, Ina-shi, Nagano; Tatsuno,

Tatsuno-machi, Kamiina-gun, Nagano; Hinode Plant, Hinode-machi,

Nishitama-gun, Tokyo; Technology Research Institute, Hachioji-shi,

Tokyo; Okaya Olympus Co., Ltd., Okaya-shi, Nagano; Olympus

Opto-Electronics Co., Ltd., Tokyo Plant, Chofu-shi, Tokyo; Olympus

Opto-Electronics Co., Ltd., Aizu-Wakamatsu-shi, Fukushima; Shirakawa

Olympus Co., Ltd., Nishigo-mura, Nishishirakawa-gun, Fukushima;

Olympus Opto-Electronics Co., Ltd., Kuroishi-shi, Aomori; Sakaki

Olympus Co., Ltd., Sakaki-machi, Hanishina-gun, Nagano; Mishima

Olympus Co., Ltd., Nagaizumi-machi, Sunto-gun, Shizuoka; Ohmachi

Olympus Co., Ltd., Ohmachi-shi, Nagano; Olympus (Shenhen) Industrial

Ltd., Shenzhen, China; Olympus Winter & Ibe GmbH, Hamburg, Germany.

 

From the similar phonetics, it might be that OK stands for the

Okaya-shi plant; NI for Nishigo-mura plant; SA for Sakaki plant.

Olympus might have had a number of other plants in the 1980th.

 

So far I have found the various codes on the following OM equipment:

 

TNxx: lenses 8/2.8, 21/2, 21/3.5, 24/3.5sh, 28/2.8, 35/2, 35/2.8,

35/2.8sh, 50/1.4, 85/2, 100/2, 100/2.8, 180/2.8, 200/4, 300/4.5,

350/2.8, 500/8, 35-70/3.6, 35-70/4, 35-70/4 AF, 35-80/2.8, 50-250/5,

65-200/4, 20/2 Macro, 38/2.8 Macro, 50/2 Macro, 50/3.5 Macro, 90/2

Macro, 135/4.5 Macro, 1.4X-A, 2X-A; cameras: OM-4, OM-4T/Ti

 

SAxx: lenses only, 24/2.8, 28/2.8, 50/1.8, 35-70/3.5-4.5, 35-70/4,

65-200/4, 50/3.5 Macro

 

SKxx: 300/4.5

 

NIxx: 40/2, 35-105/3.5-4.5

 

IOxx: 1.4X-A

 

MRxx: flash T20, T32, T1 Power Conrol

 

OKxx: flash F280

 

NJxx: Recordata Back 4

 

As you see, some lenses seem to have been produced at different plants

(according to the 3rd and 4th digit, at different time periods). On an

OM-4Ti (black), I found end of last year code "TNV7 18" indicating

that it was assembled in July 2002 (!). This camera I have seen in

Japan. As on some other OM-4Ti's, sometimes there is a 5th and 6th

digit. On another note: on some lenses produced rather late according

to their serial number, the code has been omitted.

 

Questions:

 

1) Is my interpretation of the code complete nonsense?

 

2) If the answer to 1) is no, can anybody fill in the blanks of the

production plant codes, if possible with some reference to

documentation (I myself have speculated enough about this)?

 

3) Are similar codes found on other than OM Olympus equipment (P/S

cameras, digital cameras, microscopes, microscope lenses, printers

etc.)?

 

4) Has anybody noticed other codes not mentioned in above list? If

yes, please provide full code, equipment, and if possible serial

number.

 

5) What does the 5th and 6th digit mean (as found in above mentioned

OM-4Ti; I have also seen a champagne OM-4Ti with code "TNG1 23").

 

Thanks for any help.

correction: line 4 should read: "the third letter stands for the production year with 1981 arbitrarily set as A".

My, you have a lot of free time!!! Very interesting, actually! Sorry, I can't give you any helpful info...

OM4T, TNI1 18, 1139XXX<BR>

300/4.5, TNFB, 144XXX<BR>

100/2.8, TN13, 201XXX<BR>

35/2.8, TNG4, 293XXX<BR>

35 SHIFT, TNE8, 107XXX<BR>

28/2.8, TNR4, 379XXX<BR>

21/3.5, TNEB, 121XXX<BR>

18/3.5, TNF8, 105XXX<BR>

The rest Zuiko lenses/camera bodies don't have the white letter code.

50/3.5 Macro, SAH7, 253XXX

35-70/4 ZOOM, SADA, 320XXX

Thank you, Kenny, for the list of "codes" related to S/N. When compared with my current data set, they seem to fit well with the above given interpretation.

Hi Konrad,

 

nice work, i have kept it for my documents.

 

My lens/cameras, bought as new in Germany, June 1985:

 

2.0/40 NID7, 2.8/100 TNDB, OM1 TND9

 

According to your findings all were manufactured in 1884 which is in good accordance with the date of purchase.