Unfortunately not accurate. A better account here;
garethdennis.medium.com/the-not-so-glamourous-origins-of-standard-track-gauge-2b5f1ae7e3bc
It was actually George Stephenson (hence 'Stephenson gauge') being an engineer and solving the problem he had at the time.
Thanks for that. I stand corrected. I'll fall back on QWERTY, though.
Ain't the Web great for misinformation?
sorry Jim here is the XZ1 posted the wrong link. the xz1 is 12 bit not 14 is how i picked up i posted the a74.
Jim. please stop. I'm too old and grumpy to be amused by one-line quips, however relevant, even though I do it myself. You know dam' well why I put periods in I.S.O.
Coming back thus at everything I say in this thread lowers my credibility, I reckon. If that is your intent ... I'm done.
Easy, there. The QWERTY reference had nothing to do with the periods in ISO. It had to do with the persistence of technical decisions into eras where the original reasons no longer apply.
You are missing the opportunity.
But it's I.O.S.
that would only confuse me more 😁id be posting the wrong images left right and center if i did that 🙄
The back of camera histogram has the red channel hotter than the green. But in the raw file, the red channel is significantly down from the green channels. So is the blue raw channel, which looks on the back of camera image to be close to the green.
Here is the histogram of the highlights:
- all channels are clipped in raw
- there are specular reflections
In-camera histograms didn't tell you that.
This may be irrelevant for the purpose of this shot, but it isn't universally irrelevant, far from it.
Have you checked what's going with red flowers?
of cause they are thats what makes white. and thats why i just clip the whites so everyone can see a clipping measurement. if i didnt want to clip anything
i would set 1/3 stop less exposure. but its its not part of the experiment.
No-no-no...
White in raw is not R=G=B. R=G=B on white is only true after the correct white balance is applied to raw data, and that happens in raw conversion.
BTW I doubt 1/3 would save the day.
from P1016721, clipped in all 4 channels, here is one of the greens:
No that is not correct at all.
If you fill the camera's frame with a near black object containing no whites at all you can still get clipping in the raw data if you leave the shutter open for long enough.
It is the demosaicing of the raw data and application of white balance plus whatever other number crunching is applied during the raw conversion into an rgb image that sets what is white.
While the shutter is open, the sensor's pixels are just collecting photons of light from the scene without knowing what the colours in the scene actually are. There could very well be no white in the scene at all and the raw data could still be clipped.
Yeh on a tiny part of the shiny peice of ribbon.
