Mine was a cheapo cardboard version. I was just a poor single guy learning to fly through Civil Air Patrol, so I couldn’t spring for the fancy aluminum type. Then I got married and became a poor married guy…
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A rummage through my drawer of old photo stuff unearths my “SEI exposure photometer”, adapted by me to use the Zone system.
It is a spotmeter, using the extinction principle. The viewfinder has a central gray spot. Set the film speed, then twiddle the dial until the spot matches the grayness of the surround, and read the exposure (aperture and exposure time) off the scales.
Film speed is the British Standard, natch, which is DIN plus 10. (Aren’t standards wonderful? So many to choose from.) The aperture range is from f/1 to f/32. The exposure time is from 1/500000s to 2h 47m.
The central gray spot comes from an internal bulb powered by a battery. But the brightness of the bulb depends on how flat the battery is, of course. So it also contains a photocell and moving coil meter, and a variable resistor in the bulb circuit. It has to be calibrated first by twiddling the variable resistor until the meter hits the red mark.
So far, so simple. But it also has a dial to select one of three brightness ranges which introduces neutral density filters into the viewfinder. Select whichever of these allows the gray spot to be extinguished. When reading the exposure, use the shutter speed whose background colour corresponds to the range selector. If you get the wrong exposure scale, the exposure will be wrong by a factor of 100 (6.5 stops). And another selector is for daylight or artificial light.
The meter was good for determining what exposure would put a subject tone in zone V or zone IX or whatever I wanted. I used it for 5x4 work. It was far too clumsy to give the give the range of light values in a scene, which would determine whether to develop the sheet film for N+1, N+2, N-1 contrast or whatever. I eventually replaced it with a more flexible (Minolta) spotmeter.
A scan of the instruction leaflet is at http://www.jollinger.com/photo/cam-coll/manuals/meters/SEI_Photometer.pdf
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The exposure time is from 1/500000s to 2h 47m.
Really???
How the **** do you clock 1/500000s?
Have fun!
Claes in Lund, Sweden
My thought too…
Incredible.
The PDF is very humble (“The Ultimate In Light Measurement” and a recommendation only by Ansel Adams), informative with a write up of the principle of construction and a lot of technical drawings and has a manual of operations that needs a lot of patience.
Cheap also, 268$.
I do not know from what year your price comes from,
but $268 in 1948 is worth $3,356.52 today…
I was a bit sarcastic…
But it could hit a phone pole from 100 feet!
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I don’t suppose many cameras in the 1950s could do 1/500000s, but that time at f/1 is the same exposure as 1/1000s at f/22, assuming no reciprocity failure.
According to James's Light Meter Collection: SEI Photometer, the price in 1960 was $180.
Video with Mr Adams using a SEI meter: Ansel Adams: Technique & Working Methods - YouTube . He didn’t do my trick of adding a zone scale. I expect he didn’t need to, and could do the required calculations in his sleep.
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Today too, but it must have been technically possible at least 1900. I would take the principle of a bandsaw, speed it up from 30 to 100m/s and have a slit of 0.2mm in it. Let that run in front of the film like a back shutter of a SLR, add a leaf shutter in front of it and you have half a millionth of a second. You would need a lot of light, even like today in high speed photography.
That would be about $2000 today, reasonable for a professional tool. I found a Gossen spot meter for 2500€ and there were more with 4 digit prices. Precision is expensive.
I found the price on the manual you linked to.
The video is fascinating. And perhaps also a reminder not to fully rely on the computer in the camera. Switch to spot and have a look at the shadows from time to time.
Ofcourse nice to see the olden tricks :), but overexposure want as destructive then as its now, and likewise underexposure is far less of an issue these days compared to the film days .
So I would always extract a healthy 1ev or more then what a tool like this says. I don’t even trust the meter in my camera :).
The X-H2 can do 180000 electronically so we are slowly reaching it, at least in consumer cameras. Still a long way off to 500k though
I may be one of the few survivors from using a method of extending dynamic range from that era:
rubbing warm or concentrated print developer into the highlights before they go into the stop bath in the dark room
I think the chemistry killed all the others off
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Never heard of that one. Does it get details into the highlights? Better than burning?
Changing temperatures and concentrations to push or pull was as far as I have gone.
you saw this?
might be relevant to the discussion
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It does work, but is a bit of a cheat, burning is better
Hoping this topic is appropriate for two pictures taken with the 30s Zeiss ikonta and Nokia dumbphone shown below
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Here’s mine (I wish):
I do have a Sekonic L-398 battery-less having sold my complicated electronic Gossen long ago.
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What a nice piece!
Are there levers on the backside?
Yes, if you search the internet there is view of the back which I
unfortunately didn’t download …
There is a nice blog entry with the system of levers and a page out of the manual.
I’ll ask if I may copy the image into this thread.