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Asher this one is for you!
EF 50MM f1.2L Prime 1/80 f4.0 ISO 400 1DsMKIII MR14EX Ringlight

EF 50MM f1.2L Prime 1/80 f4.0 ISO 400 1DsMKIII MR14EX Ringlight
My tools show (for the image as posted) the embedded profile to be sRGB IEC61966-2.1 and the (declared) color space to be sRGB.And there is something strange in your EXIF colorspace info, the picture seemte to be made with a profile named Z009, but EXIF states that it is sRGB. When one 'picks' colors directly from a non-colormanaged web-browser they probably get wrong readouts.
Of what? I've lost track of the bidding.More proof:
That could well be.http://regex.info/exif.cgi
Nice tool. Thanks for the link.
I think I found it, Z009 seems to be the Canon's own profile that resembles sRGB. So it probably is no problem substituting one for the other.
Ah, yes. Thanks.I used the direct link to the black-grey-white image Will posted.
I used the direct link to the black-grey-white image Will posted. The other pictures have sRGB attached, but that one gives a warning
WARNING: Embedded color profile: “Z009”
All Windows web browsers (except Safari) and many Mac web browsers ignore an embedded color profile . . .
Doug:
My Eyedropper says =425, but then I think it is calibrated in ml or cm3.
Why? The gray here is arbitrary, and the "exposure" was set to place black at the bottom and white "above the top". The gray, whatever gray that is, will fall where it falls.The center spike should be at the center.
Nothing "went wrong" - Will pulled the handles until it came out that way.If this was the calibration target, do you think the image was overexposed or something else went wrong?
Why? The gray here is arbitrary, and the "exposure" was set to place black at the bottom and white "above the top". The gray, whatever gray that is, will fall where it falls.
By the way, what does the center of this particular histogram scale represent (in terms, for example, of relative photometric exposure - we often say "relative luminance")?
Nothing "went wrong" - Will pulled the handles until it came out that way.
In any case, it is an unwarranted assumption that:
• all "gray" targets (or the gray portion of a black-gray-white target) have the same nominal reflectance. (The value R=0.18 is often tossed about in this regard, but many targets, especially if primarily intended for white balance color correction purposes, have nominal reflectance much different from that.)
• the camera metering system will always call for an exposure such that the gray portion of the target will have a certain photometric exposure (for example, as a fraction of "saturation") for any camera, in any operating mode.
• the exposure result of that photometric exposure will fall in the middle of the exposure axis scale of any given histogram.
If you want proper exposure, you want the gray in the middle. In fact, when I spoke with an **engineer** (just like you and I) of a major light meter manufacturer to calibrate my light meter, he suggested using the black, gray, white gray card to ensure that the gray was in the middle. This can be especially helfpul if you are using filters on your lens and want to ensure you have the proper adjustment factor on your light meter.
To suggest the gray spike can be anywhere is odd, at best. Watch the video I that I referenced.
Will pulled what? Maybe stop pulling would be a good idea?
The exposure is off and nothing in your post refutes that. The whites are blown, and hence we're seeing in the photograph that the red channel looks clipped. See how this is all coming together?
The black and white need to be at either end of the histogram and the outer curves should hit baseline. Actually, the end to the right, in the bright areas is not the end. The camera MFRS, TTBOMK, add a little buffering space to prevent clipping. so essentially you are correct with the caveat that more data may be stored in RAW than the sRGB histogram appears to show.
Only problem, of course, is that the final result that was posted shows a clipped channel. Otherwise, excellent comment concerning expose-to-right. If the red channel were not clipped and eye whites were at least warm (I'd settle for off-neutral), then this whole discussion would never have taken place.
Perhaps you and Will can help me understand the photograph process. In your post above you discuss gels. And I believe Will discussed reflections. And now we have gray cards for white balance. I am not sure if Will's use of a gray card was to set his exposure, set custom white balance on his camera, or set a white point in post production.
And I assume that the card was used with the gelled flashes and ambient reflections? If true, then reflections should be neutralized?
Anyway, I am done. Will is happy with his photograph. So I am happy. I trust the model is happy too. Everyone wins.
The difference being, of course, is that when others create creamy waterfalls or whatever, they delilberately play with the post-processing to create an effect. They do not say in effect (paraphrasing), "the color is true, here's the gray card." They know the color is not true because they deliberately altered it to create a correct pleasing effect.Following the example of creamy waterfalls and rivers, they are beloved by the world although entirely wrong in terms of accuracy! That's how I think about Will's color here. He like's it and that's his choice.
Odd color? I have no clue. I would have to know ~exactly~ what Will did. As far as the software is concerned, it just assumed r=255 where blown. It has no other information to work with. It's like a 10V meter measuring a voltage of over 20V. It has no clue as to the true value other than it exceeds 10V.One issue is that the software might look at the clipped higher end and not take into account that only one of the 3 channels is truncated. That, perhaps is a source of the odd color. It might be just what will likes, but to me it's odd.
Or, does anyone know better on how the various RAW processing software teats the high end when there's uneven clipping?
he over-exposed beyond the right edge of the histogram more between 1/3 to 1 stop but without getting marching ants evidence of blown specular highlights. That's all.Odd color? I have no clue. I would have to know ~exactly~ what Will did. As far as the software is concerned, it just assumed r=255 where blown. It has no other information to work with. It's like a 10V meter measuring a voltage of over 20V. It has no clue as to the true value other than it exceeds 10V.
@Kevin,
It's probably an 18% gray card, so why should it be in the middle of the histogram? I think you are confused because an 18% coverage of black ink APPEARS as halfway between white and black to us humans...
The location of the gray spike does not matter that much, PS or any other color-correction program just needs a spot with a gray. If it's a dark or light gray does not matter, only thing PS does is make the RGB values the same for that spot.
And in that respect the histograms are VERY informative! If you look at the gray spike in R, G and B separately, you will see that the blue spike is a little less wide to the left than the red and green spike. That means that towards the darker tones, there will be a tiny yellowish cast. Looking at the blue component of the black spike you see this confirmed, because there is less blue in what we suppose should be black then there is red and green (thus yellow). If you start probing the picture with the eyedropper tool (set to a 30x30 sample), you notice that towards the edges there is some color variation that could explain this shift.
When you try to correct this using PS's curves and eyedroppers, you will get this:
You can clearly see that near the blue spikes undershoot, PS lets the curve drop a little to make it a 'true' RGB gray. That is a correction for yellow cast. The green and red curves are a straight line, they need no correction.
You will also notice that the black are more defined, but that mainly is because there is no 'real' black in the picture. When color-correcting a daylight scene, I would only use the white and graypoint, and up the contrast later by hand.
I don't remember what target Will said he used for his now-infamous black-gray-white image, but as posted (and we have no idea how much white clipping is in play - maybe little or none), the gray appears to have a relative luminance of about 63%.
Actually, in this image, the rectangular overlay panel is "50% coverage gray" (in graphics arts terms), and is also 50% relative luminance (its sRGB coordinates are 219,219,219):If you would make a 50% coverage grey, it would appear in the middle of the histogram, but we would judge it as much to dark to be visually 'middle gray'.
LOLHere's the point Joachim, now she has blue in her hair and extra green eyes when you created them.
The rightmost of these is very nice.If I wanted to give her a life-like appearance, the result would be something like this...
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