OM-D needs more light, longer exposure times! (

Started May 15, 2012 | Discussions thread
Detail Man
Detail Man Forum Pro • Posts: 16,688
Re-inventing the Wheel over and over in The Vast Wasteland ...

Louis_Dobson wrote:

Yes, but that's working with RAW.

The camera maker's job is to produce an 18% grey in JPG while producing a picture with as little noise and as few blown highlights as possible.

And ISO itself (a JPG-referenced metric entirely) is defined as reaching a standard output brightness level for 18% grey illumination of the test-target (plus or minus 1/3 EV). Since ISO has meaning only in sRGB color-space and a non-linear Gamma correction curve is applied, this translates to an even lower percentage variation in output RGB color-channel levels (around 118 out of 255).

Since (JPG-referenced only) ISO is that output level (and nothing else), it cannot be "cheated" on

How much or how little he saturates the RAW ro achieve this is his business.

Now, if you step into the process at the RAW stage, you would get a lighter or darker file - except LR automatically compensates.

If the manufacturer chooses to heavily saturate the RAW file, he will tend to gain noise performance at the expense of highlight latitude (this is the GH2 approach, where there is little highlight headroom).

If the manufacturer chooses to lightly saturate the RAW file he will tend to gain highlight latitude at the expense of noise performance (this is the Oly approach - highlights are very well preserved, but surprisingly noise is good too).

So there is nothing to test. Nobody is cheating or not cheating because there is nothing to cheat AT. Provided the pictures develop correctly, how much the maker chooses to saturate the RAW is nobody's business but his.

And where it comes to RAW recording, UniWB configurations (and the like) allow users to come as close as they may dare to the actual RAW-channel saturation limits. Done. Over. Case closed ...

PS - I think that we should start invoicing the next yahoo who starts a thread about this dim BS ...

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