I am curious as to why or when the order of e.g. "100 ASA" got reversed to "ISO 100".
Being a stubborn old git, I always write the exposure index number followed by a space then "ISO" ...
OT, but I always write f/4 as opposed to referencing a Douglas Phantom jet airplane ...
Something I also have been thinking. The ISO sign came in film roll packs in 1990 tale as an alternative of ASA. I still wonder the definitions of ISO and ASA are different.
And I wonder the definition(s) of ISO was also reason to much the confusion about "exposure" or "exposure triangle" in beginners discussions.
If somebody knows, answer please!
I can’t see that it makes any difference which comes first. There seems to be no confusion as to the meaning.
Since 1974. Film containers denote their speed as (e.g.) ISO 100/21°, including both arithmetic (100 ASA) and logarithmic (21 DIN) components. The second is often dropped, making (e.g.) ISO 100 effectively equivalent to the older ASA speed.
Obviously everyone knows what it means but that is not my concern.
OT but, along similar lines, it bothers me when someone who shall be nameless writes "a74" instead of "alpha 7 Mk. IV" ...
... or when someone elsewhere writes "SDQ-h", not "sd Quattro H" .. I could go on but Danno is probably circling ... :-)
You say po-tay-to, and I say po-tah-to.
I’m an ASA man, till the day I die.
Hope you've been keeping that in your freezer all this time...
I was referring to common usage in the literature.
I remain curious as to why or when the order of e.g. "100 ASA" got reversed to "ISO 100".
Note that on the Kodachrome II box it's ASA 25, not 25 ASA. The DIN index is the other way around.
missed that ... thank you!
Cool ...
Hi,
It's probably due to the way things are said in French vs English. Such as UTC for time when we say UCT....
Stan
My (faded) memories are of making and hearing references to “ASA 100”. I don’t remember the reverse being a thing — but maybe this was only true of the crowd I ran with.
The ISO standard (12232) mandates that 'ISO' should come first when reporting ISO values. I'm guessing that the order changed when it changed from specifying which of several national standards was being used to an international one under the jurisdiction of ISO. ISO likes to promote itself, so it comes first in all ISO standards.
So syntactically, the suffix 'ASA' was there to clarify which standard you were talking about. whilst the prefix 'ISO' is there to tell you that it's the real, international thing.
AKA someone who shall be shameless
Hi,
Ah, yes. Of course the ISO says thou shalt put our name first. :P
And that, right there, explains it all. ;)
Stan
I prefer Ella and Louis -
www.youtube.com/watch?v=J2oEmPP5dTM
Same difference 🧐
Stan, the French is TUC fr.wikipedia.org/wiki/Temps_universel_coordonn%C3%A9 ,,,
... not popular in England because of the infamous TUC (Trades Unions Congress) - well, not popular with the Tories anyhow.
Hi,
Might be why it's Universal Time Coordinated. Even the French time signal stations (for the radio frequency calibration standards) says UTC.
The US ones say Universal Coordinated Time.
We used to call it GMT, Greenwich Mean Time. But then I'm old! :P
Stan
The Why is trivially simple: Two different standards organizations wrote the standards. The When was detailed above in the Wikipedia quotation.
The question was more obout the order it is written, as in 100 ASA vs ASA 100.
I think that the manufacturers always used "ASA 100/ISO 100" but the public often preferred the 100 ASA/ISO version.
The earliest I can find printed on a film box has that ASA first version and was like that since.
But I cannot think of many customers saying "I'll have an ASA 100 film" as opposed to "I'll have a 100 ASA film"
Unless they meant "I'll have an ASA 100 film ASAP"
