shutterfiend
cheap and lazy
I recently acquired one!
I have the usual question, how to use it?
I went to the following website:
http://www.photoethnography.com/ClassicCameras/lightmeters-classic.htmlhttp://www.photoethnography.com/ClassicCameras/index-frameset.html?lightmeters.html~mainFrame
I followed the instructions and found the column that matched the letter. I figured out what the Scheiner degree to ASA conversion should be. Now what? I don't know what Scheiner degree the column I matched represents.
I have the usual question, how to use it?
I went to the following website:
http://www.photoethnography.com/ClassicCameras/lightmeters-classic.htmlhttp://www.photoethnography.com/ClassicCameras/index-frameset.html?lightmeters.html~mainFrame
I followed the instructions and found the column that matched the letter. I figured out what the Scheiner degree to ASA conversion should be. Now what? I don't know what Scheiner degree the column I matched represents.
Bryce
Well-known
While I don't know what the manual would say, I'd compare an electronic meter's readings to establish the meaning of the values from your extinction meter. You'll never HAVE to buy batteries again, but I bet you will anyway...
jlw
Rangefinder camera pedant
Believe it or not, I've got a Drem Instoscope right here. (Is RFF a great place, or what?) As you probably know, this is an "extinction" meter -- you sight through it toward your subject and note the dimmest letter you can read through the little eyepiece. (It helps to standardize your viewing time so your eye always has the same amount of "dark accommodation.")
And you've sussed out that the Scheiner degree number represents film speed settings; it was a predecessor to the ASA/ISO numbering system. (There's a conversion table here - click.)
Now that you know the Scheiner number that corresponds to the speed of film you're using, you have to set it on the calculator "drum" that forms the body of the Instoscope. Look at the knurled section just below the eyepiece and the letter scale below it. Under the letter scale, see the red pointer to the left of the red filter-factor numbers? (On my Instoscope, it's just below the letter "D.") That pointer is the index for film speed -- set it so it lines up with the correct Scheiner degree number on the red-numbered scale below it. The leftmost range of numbers on the Scheiner scale is 17-19, and the rightmost is 29-31. This corresponds to ISO speed ranges from 4-6 to a blistering 64-100.
With the meter set for the correct film speed, look through the eyepiece and note the dimmest letter you can read. Find that letter on the scale just below the knurled ring. Now read straight down the column below that letter.
The numbers in the column represent shutter speeds that will provide correct exposure, when used at the f/numbers in the vertical red bands spaced around the drum. In case the red f/numbers have faded on your Instoscope (as they have on mine): the top row is for f/1.4, the next row is for f/2, and so on down to the bottom row, which is for f/22.
So for example: If your film speed is 26-28 degrees Scheiner, and the dimmest letter you can read is "B," you'd read straight down the B column and come to a row marked 1/300. That's the correct shutter speed if you're using f/1.4. The other rows farther down are equivalent exposures for the same light level: 1/100 at f/2, 1/50 at f/2.8, and so on.
See how it works?
Just for yocks, I just now set my Instoscope to Scheiner 31 (ISO 100), pointed it at the frosted glass on a kitchen light fixture, looked into the eyepiece, counted to 10 (to let my eye accommodate) and noted the dimmest letter I could read; it turned out to be V. I looked down the V column and found that the indicated exposure was 1/25 at f/11 (or its various equivalents.)
Then I put the reflected-light attachment on my Minolta Flash Meter IV, pointed it at the same frosted glass, and took a reading at ISO 100. The result: 1/30 @ f/11-and-a-half... only 1/2 stop difference!
And you've sussed out that the Scheiner degree number represents film speed settings; it was a predecessor to the ASA/ISO numbering system. (There's a conversion table here - click.)
Now that you know the Scheiner number that corresponds to the speed of film you're using, you have to set it on the calculator "drum" that forms the body of the Instoscope. Look at the knurled section just below the eyepiece and the letter scale below it. Under the letter scale, see the red pointer to the left of the red filter-factor numbers? (On my Instoscope, it's just below the letter "D.") That pointer is the index for film speed -- set it so it lines up with the correct Scheiner degree number on the red-numbered scale below it. The leftmost range of numbers on the Scheiner scale is 17-19, and the rightmost is 29-31. This corresponds to ISO speed ranges from 4-6 to a blistering 64-100.
With the meter set for the correct film speed, look through the eyepiece and note the dimmest letter you can read. Find that letter on the scale just below the knurled ring. Now read straight down the column below that letter.
The numbers in the column represent shutter speeds that will provide correct exposure, when used at the f/numbers in the vertical red bands spaced around the drum. In case the red f/numbers have faded on your Instoscope (as they have on mine): the top row is for f/1.4, the next row is for f/2, and so on down to the bottom row, which is for f/22.
So for example: If your film speed is 26-28 degrees Scheiner, and the dimmest letter you can read is "B," you'd read straight down the B column and come to a row marked 1/300. That's the correct shutter speed if you're using f/1.4. The other rows farther down are equivalent exposures for the same light level: 1/100 at f/2, 1/50 at f/2.8, and so on.
See how it works?
Just for yocks, I just now set my Instoscope to Scheiner 31 (ISO 100), pointed it at the frosted glass on a kitchen light fixture, looked into the eyepiece, counted to 10 (to let my eye accommodate) and noted the dimmest letter I could read; it turned out to be V. I looked down the V column and found that the indicated exposure was 1/25 at f/11 (or its various equivalents.)
Then I put the reflected-light attachment on my Minolta Flash Meter IV, pointed it at the same frosted glass, and took a reading at ISO 100. The result: 1/30 @ f/11-and-a-half... only 1/2 stop difference!
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shutterfiend
cheap and lazy
jlw,
Wow! Thanks! It's the great people on RFF that makes it truely great!
Bryce,
Thanks. I'll probably end up buying a "real" meter eventually (with a battery and digital read out and all). It's just hard to find them at garage sales for a buck!
Wow! Thanks! It's the great people on RFF that makes it truely great!
Bryce,
Thanks. I'll probably end up buying a "real" meter eventually (with a battery and digital read out and all). It's just hard to find them at garage sales for a buck!
Bryce
Well-known
Shutterfiend- Surely you've got a camera with a working, built in meter that you can use? Anyhow, sounds like JLW has offered a direct solution.