exposure iso to schnieder

[robert fallis]

I've just got a Johnsons exposure calculator, but the film speed is marked in Sch. is that schnieder? what I need to know is the iso equivulant of 36,33,30, 27 24 degree.sch.
can any one help?

thanks
bob

[Nick_3536]

Isn't that what became DIN?

http://www.film.project-consultant.n...a_din_iso.html

Why not use Sunny 16 to check out the meter?

[Dan Fromm]

Schreiner, I believe.

[Bob Salomon]

There have been several film speed idexes.
Weston
ASA (now ISO) these are BSI arithmetic scales.
ASA Additive
B.S.I. Log - what you are asking about - Schneiner.
DIN

For an ISO of 100 the various systems would be set at:

Weston 80
ASA Additive 5°
BSI Log - Scheiner 32°
DIN 22

for 400 ISO they would be:

Weston 320
A.S.A. Additive 7°
BSI Schneiner 37°
DIN 27

Since there is no numerical correlation between the systems the corresponding values can only be approximate.

The Photo Lab Index does have a chart of approximate conversion values on page 10-01 of supplement #137.

[Helen Bach]

Rudolf Kingslake suggests this approximate conversion:

Scheiner = DIN + 8,

or Scheiner = ISO logarithmic + 8

Convert from ISO arithmetic (or ASA) to ISO logarithmic (or DIN) = 10 log ISOarithmetic + 1.

So for ISO arithmetic speed of 100
DIN = 21
Scheiner = 29

According to Kingslake the Scheiner - ISO correlations you are asking about would be roughly
36 - 500
33 - 250
30 - 125
27 - 64
24 - 32

Best,
Helen

[FrankstaPasta]

Hi, I'm very new here and just made an account and posted because I wanted to be useful
So I bought a Agilux Agifold today (It's a beaut) and I found advice on the internet hard to follow as there were many contradictions and lots of waffle
So I was messing about, using my SLR as a comparison I set the ISO on it to 400 and figured out that it was the same as the "30" setting on the old bellows camera
I don't know if this is for all cameras with a SCH dial, but I figured out that:

100 ISO is 24
200 ISO is 27
400 ISO is 30
800 ISO is 33

That's all there is on the camera, I've got some 400 ISO film I'm gonna use so I'll report back if it's all good Happy LF-ing

[Jim Jones]

The previous chart seems closer to an ISO to DIN conversion than to a Scheiner conversion. A conversion chart on some Gossen meters gives this:

DIN = ASA = Scheiner
15/10 = 25 = 25
18/10 = 50 = 28
21/10 = 100 = 31
24/10 = 200 = 34
27/10 = 400 = 37
30/10 = 800 = 40

[Jim Noel]

There is a difference in American Scheiner and European Scheiner. Later I will look up my comparison chart.