ASA Film Speed


TPF Noob!
May 23, 2006
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What exactly is ASA film speed? is it some sort of rudimentary ISO level? Thanks
why must they fiddle with everything??

but americans use ISO now dont they because europeans used Ghost when americans used ASA?
ISO is the International Standards Organization, rather than just a national's newer than the old a lot of things have gone over to ISO.
that is totally strange how the ISO levels are an organisation's name! i thought the S stood for Sensitivity and the other two something else. How weird. Thanks - Big Mike has been ever so patient with me being a noob!

I am really beginning to get the hang of it and i am having a lot of fun with all the lenses.
There'se always been a lot of confusion regarding these abreviations.


Plus I think the the Japanese had their own at one time.

ASA = American Standards Association
DIN = Deutsches Institut für Normung
ISO = International Standards Organization
GOST = Gosudarstvennyy Standart ( as found on Zenits and Feds LOL )

Actually sensitivity is one of the few American measurements that the world has embraced. The European standard was for the most part DIN. ISO is an agreement by all countries to use a standard form of measurement to avoid confusion. The clock is ticking on the USA and the UK switching to kilometers.

To refer to sensitivity as ISO is a bit ridiculous, you may as well say you were driving at 60 ISO or that you weigh 92 ISO.

But that's how it iis, we've all got used to it I guess.

Well I'm off to heat some water to 100 ISO and enjoy a tea :)

To say it simply: yes, ISO film speed is the same thing as ASA film speed. They mean the same thing, and can pretty much be used interchangably. It just depends on how american you are ;)

Generally these days most people in America call it ISO anyway. I think ASA is falling out of use these days.
OK, thanks. It just worried me that my camera had no ISO settings and the manual obviously couldnt tell me about the changes as it isnt prophetic.

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