In article , Me says...

On 28/05/2017 9:11 PM, Alfred Molon wrote:
In article , Me says...

On 28/05/2017 1:31 AM, Alfred Molon wrote:
In article , Me says...

On 27/05/2017 5:19 PM, Alfred Molon wrote:
In article , Me says...
Oh nice.
Bill Claff has produced an interactive chart showing comparison between
set ISO and measured ISO.
Olympus OMD E1 MkII overstates real ISO by 1.23 stops!
Something many fanboys won't want to accept I guess - those ISO3200
shots are actually only ISO 1365 - LOL.
He's also measured base/native ISO is ISO 200.
http://photonstophotos.net/Charts/Measured_ISO.htm

He measures ISO 83 both at ISO 64 and ISO 200 with the Olympus E-M1 II.
But the exposure time at ISO 64 is three times longer than at ISO 200,
so clearly this Bill Claff is wrong.

DXO say the same, so no, Bill Claff is not wrong:
https://www.dxomark.com/Cameras/Comp..._1136_1070_909
Olympus lie about ISO. Big lies - Trump style lies.

No.

If the exposure time at ISO 64 is *three times* the exposure time at ISO
200, then both ISO settings do not have the same "true ISO" of 83.

That is a *fact* and if DXOMark or whoever say otherwise, they are
wrong.

Don't be silly.
Base ISO (set in camera) is 200 = real ISO 83. This answers your
original question about "native" or "base" ISO of the sensor.

If you don't want to believe that Olympus OMD EM1 real ISO is 1.23 stops
below stated ISO, bully for you.
I don't really care.

You should stop parroting what you read on the web and start using your
brain.

If the exposure time at ISO 64 is three times the exposure time at ISO
200, then both ISO settings can't be the same "true ISO" 83 as claimed
by DXOMark.

Or do you have an explanation why the exposure time at ISO 64 is three

The answer to your question is obvious - so use /your/ brain - instead
of assuming that everybody who disagrees with you or questions what you
states are as stupid as you are - and insulting them.
*Olympus overstate ISO as a deliberate con for marketing purposes. Much
the same as VW (and other car makers) understate emissions.
The fact that few people seem to give a **** about deception by
dishonest companies isn't the issue.
Don't whine that I'm being nasty by calling you stupid - I may have been
nasty about a deceptively marketed product you're a fanboy of - but you
started with a personal attack.

*all the makers tend to overstate ISO, but none as consistently extreme
as bull**** artists Olympus.

You are just bull****ting around without addressing the real issue.

Once again: explain why at ISO 64 the exposure time is THREE times the
exposure time at ISO 200.

The DXOMark site you are referring to claims that both at ISO 64 and ISO
200 the real ISO is 83.

But if the real ISOs at ISO 64 and 200 really both were 83, the exposure
times should be the same. They are not, so DXOMark and you are wrong.
--
Alfred Molon

Olympus E-series DSLRs and micro 4/3 forum at
http://tech.groups.yahoo.com/group/MyOlympus/
http://myolympus.org/ photo sharing site