Watkins Bee Meter

The Watkins Bee Meter was the first commercially successful exposure meter, introduced in the early 1890s and still in use 40 years later: the Watkins Speed Card reproduced at the foot of this module ('39th year of issue') dates from August 1931. By modern standards it was staggeringly inconvenient in use, relying as it did on counting how long it took for a piece of sensitized paper to darken to a specified tint.

bee meter + box

Once you had finished counting ('Make no attempt at great accuracy, a rough approximation is sufficient'), you had to line up your intended lens aperture with the plate speed on the left, and then read the indicated exposure opposite the darkening time on the right.

Some idea of just how inconvenient this was can be garnered from the instruction book ('17th Edition') reproduced below - which also serves to remind us that before the days of ASA speeds there were many conflicting speed systems, and that the speed quoted on a box of plates or films often owed as much to the marketing department as to hard science. For that matter, even diaphragm markings were not standardized, as you can see on page 1 of the instruction book.

The Bee also reminds us of how slow progress was in those days, and of the limits of certain technologies. If the paper had darkened any faster, it would have reduced the accuracy by making it harder to say exactly how long it took for the paper to darken to the specified tint. Of course the 1930s saw the appearance of photoelectric exposure meters, most notably the Weston. These were far faster and more reliable, and as soon as they appeared, the Bee's days were numbered.


Bee meter and box

'Booklet, instruction card and speed card enclosed'. The meter is about 45mm/an inch and three quarters in diameter. Very roughly, 5/- (five shillings) equated to £8-10 in 2010 purchasing power ($12-15 or 10-12€). A refill, at 11d (see instruction book, below) would be just under £2 ($3 or 2,50€).


short instructions front short instructions back

booklet cover

page 1

pages 2,3

pages 4,5

pages 6,7

pages 8,9

pages 10,11

pages 12,13

pages 14,15

pages 16,17

pages 18,19

pages 20,21

pages 22,23

pages 24,25

pages 26,27


pages 30,31

page 32,back

Plate and film speeds


speed card front

speed card back

Film speed cards were updated regularly: the date of this card is printed on it. New cards, at threepence halfpenny, post free, would equate to maybe 60p, 75 euro-cents or just under $1 today. They were often paid for with postage stamps.

The fastest plates and films on the list are mostly 500, equating roughly to ISO 25 to 30 - though as the instructions make clear, true comparisons between different speed systems are rarely if ever possible. Plenty of plates were around one-eighth of that speed, ISO 3 or 4: around the speed of modern photographic printing paper.

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© 2010 Roger W. Hicks