So... I finally come to a decision to go with the OM-D... Is there any big hand users out there?

Started Mar 13, 2013 | Questions thread
texinwien Veteran Member • Posts: 3,326
Re: Issue 1: inconsistent in-camera ISO labelling

Jack Hogan wrote:

texinwien wrote:

My gosh, so many words, so little time. There are two issues here:

"The issue is that if you take in-camera ISOs at face value you end up comparing apples to oranges, especially with the EM5 which is a relative outlier in its ISO interpretation"

Ok. Point out the misconception and erroneous conclusion here.

No sir, we're going to do this the other way. I have pointed out the error in your first 'proof' that your idea is correct.

Yes you did, misrepresenting my post.

Please point out the misrepresentation. Your proof offered two images - one (the G3) that was exposed based on the ideal (saturation sensitivity), and one (the E-M5) that was exposed based on camera ISO Setting, one full EV lower than the ideal.

And you thought that was proof that the variance between saturation sensitivity and camera ISO setting that is allowed by the standard could be used by Olympus to 'fake' better noise performance.

It looked good. Convincing to someone who doesn't take all of the variables into account. But the fatal flaw was your failure to equalize exposure.

And your train jumped the tracks when it stopped in at the station where you thought that underexposing a file (compared to the ideal) could ever possibly be used by a camera company to 'fake' better noise performance than a camera actually offered.

When the reality is, in the truest and most literal sense of the word, the exact opposite.

You can't underexpose a file to fake better noise performance. No, underexposing a file 'fakes' poorer noise performance. That's right, underexposing by a full EV, then boosting the gain (as the E-M5 does, according to DxOMark) amplifies noise. It actually makes it look as if the E-M5 is worse regarding noise than it actually is if carefully and ideally exposed.

Dastardly Olympians, eh?

To follow a train of thought one needs to read all of the posts in a thread from first to last, not just a snippet here and one there, otherwise they may miss context.

Ok, shoot - point out my error above. Why did you drop that 'proof' like a hot potato after I picked it apart? Why haven't you addressed the context I missed along the way?

Which is why, to help us, I summarized them in these two simple posts.

Yes, both wrong.

Issue 1 is pretty straight forward and hard to argue against, isn't it?

Not at all, and I already have. Comparing any number of cameras based on camera ISO Setting, as long as we know that all of those cameras have had their ISO settings measured and verified by a trusted third party using the SOS method (as DPReview does) is completely valid, as long as exposure was set carefully and correctly in all cases.

And, since the vast majority of consumers will only ever expose based on camera ISO Setting, it's not only a valid method of testing, it's also the one that's most useful for the audience who will be buying and using the tested devices.

Let's move on to Issue 2).

Yes, let's. I'm so excited!


 texinwien's gear list:texinwien's gear list
Panasonic Lumix DMC-GM5 Olympus E-M5 II Olympus 12-40mm F2.8 OnePlus One Canon EOS 300D +20 more
Post (hide subjects) Posted by
(unknown member)
(unknown member)
(unknown member)
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow