ANSI standards and Exposure metering

[pankaj_dubey1]

<p>Sorry, I have to start a new thread but I had read somewhere that the ISO ANSI standard of 1974 for calculating metering is a paid document .<br>

I have found the equivalent free Indian standards Institute document which claims to be based on ANSI 2720:1974<br>

.<br>

It is here:<br>

ive.org/download/gov.in.is.10917.1984/is.10917.1984.pdf</p>

<p>I have not been able to find the 2011 revision of the NASI document.<br>

HTH</p>

<p>Pankaj</p>

[BrianS1664879711]

<p>I believe the 2011 version is just a revalidation of the earlier issuance.</p>

<p>ISO 2720: 1974 (the ISO instantiation of ANSI PH3.64) was revalidated in 2011. If it was just a revalidation and not a revision (which I believe it was) only the date on the front cover will have changed. But I'm not interested enough to spend the $50 or $88 price to buy a copy. :)</p>

<p>The Indian standard is quite interesting. They violated ISO copyright and then put their own copyright on it using a "freedom of information for disadvantaged communities" philosophy. But times appear to have changed because now they charge many rupees for "bootlegged" standards.</p>

[pankaj_dubey1]

<p>This pdf is not made available by ISI but by another oragnization under the RTI rule of 2009.<br>

The ISI version is 211 rupees(USD 3).</p>

<p> </p>

[BrianS1664879711]

<p>Ahhh, thanks for the correction. And thanks for doing the currency conversion. I looked quickly at the list of other engineering standards at ISI and thought I saw thousands of rupees... but did not know the exchange rate until now. It is a lot less expensive to buy the ISI version of 2720 than the ISO version!</p>