Camera histogram vs LR histogram

I generally adjust dslr expose using the histogram on the camera (doesn't matter what kind), so that there are no or minimal blinkies.
Since LR3, I've noticed that I have a third to a half stop of exposure remaining to the right of the LR histogram.
Anyone else notice this, and if so, what are you doing about it?

This is standard. The histogram on the back of the camera is based on the JPEG preview the camera generates from the RAW file. The histogram in Lightroom, if you're shooting RAW, is based on the RAW file itself, and thus you're going to have some more headroom.
If you want it to be closer, adjust the JPEG settings in-camera to be as flat (low-contrast) as possible, and you may get a smidge more, but still, this is SOP and LR is behaving correctly.

Similar Messages

Histogram – LR vs. in-camera

I had learned not to trust the in-camera histogram, especially regarding highlight clipping. Usually those areas turned out fine in LR.
Then I came across this article: Settings for an Accurate Histogram
It totally made sense, and I adjusted my camera's setting accordingly. While images now look even more flat on the internal screen, I get much less of those clipping warnings, and I can confirm that from examining the images in LR.
It certainly brings the in-camera histogram more in alignment with LR's.
Just wanted to pass this on for others.

martin-s wrote:
Then I came across this article: Settings for an Accurate Histogram
I would suggest you interpret the title of the article as "Settings for a *more* Accurate Histogram". No matter what settings you make in the camera you will still not see a histogram of the *raw* data.

Camera set to sRGB, Opens as Adobe RGB

I have a Canon 5D, color space set to sRGB. When opening RAW file in Camera Raw 5.0, it opens as Adobe RGB. How can I fix this?
Thanks!

> Wouldn't that be true only if you were targeting a smaller space, like sRGB?
Factual clipping, i.e. pixel saturation on the raw level has nothing to do with the intention regarding the processing of the raw image. If pixel saturation is reached, then the raw pixel value is invalid.
The issue is, how one can achieve an in-camera conversion, which resembles the closest the raw data, in order to be able to tell how the actual exposure was. There are several steps, which can not be neutralized for the in-camera conversion, one of them being the color space conversion. Furthermore, the spectral characteristics of the color filters play a huge role in this question, so my suggestion is camera model related.
For example re the Nikon D300 I suggest using Adobe RGB in-camera. This is, because Nikon changed the color filters for the D300 sensors from the previous models very much. They are almost always changed from one model to another, but this change was extraordinarily big: the transmissity of the red range is much larger in all three filters than with other sensors. This has lead lots of photographers believe that the "red channel overexposes" (which occurs very seldom, practically nie before green saturation). Thus my (unproven!) suggestion is, that the in-camera histogram and clipping indication of the D300 gets closer to reflecting the raw data with Adobe RGB than with sRGB.

Information in Histogram in Adobe Camera RAW

Since I capture my images in RAW, when I open them in Adobe Camera RAW (via Elements 11), what information is displayed in the image and the histogram I see?
Is it showing me the jpeg created in the camera? If so, the jpeg settings in my camera are not only important in viewing the LCD and the histogram in my camera at the time of capture. They would also be important in viewing my image when it first opens in Adobe Camera RAW.
Thanks for some input.
Mary Lou

I have an answer to this question supplied to me from a forum on www.luminous-landscape.com. It is as follows:
Re: Understanding Camera RAW article
« Reply #3 on: September 30, 2013, 05:20:22 PM »
Reply Quote
Quote from: mlfrost on September 30, 2013, 05:14:21 PM
Perhaps you can answer a related question on Camera RAW. When I open an image captured in RAW format, I see an image and histogram in Adobe Camera Raw. Am I correct in assuming that the opening image and histogram are created from the camera's jpeg settings?
No...Camera Raw rips the entire raw image and does a demosaic and application of ACR defaults to generate the preview and the histogram (which is displaying the resulting graph based on the output color space set in ACR Workflow Options). ACR doesn't use ANY settings from the camera's JPEG settings and the only thing that ACR uses from the raw file is white balance info and the ISO metadata...

Histogram inconsistencies with Camera profiles - Camera Raw

Hi,
I've been going nuts with this issue for a year now since Adobe released the camera profiles for Camera Raw. Something tells me this shouldn't be happening.
Well exposed pictures taken with the D300 show an inconsistent histogram in camera raw when using the Adobe camera profiles for the D300.
This is a shame because I prefer the colour rendering of the camera profiles to that of the adobe standard profile.
This is the problem:
With the D300 I get a correct histogram in Camera Raw only if I choose the ACR 4.4 or the Adobe Standard profile. By correct I mean with black and white points filled to the edge of the histogram.
If I choose the camera neutral, standard, portrait or vivid suddenly there's an empty area in the histogram's blacks. Effectively the black point has been shifted quite a bit and I need to push up the slider for blacks up to 30 or so to get the black point back to the right place. While with Adobe standard the blacks are correct at 0 or so. Check out the pics here below.
Is this normal behaviour, or is there something wrong in my settings?

Nice pic of brain Bill. Still, I would take it without any harsh light and rather use longer exposure with tripod. You can see some sort of light source in left bottom part of brain. I assume it was a flash gun or above by lamp. Then you may get much better result ;-)
Thanks. The shot was taken using the Nikon R1C1 closeup flash unit using the diffusers to help eliminate glare. With such specular sources, one must adjust the light sources carefully to avoid glare, but the only sure way to eliminate the glare is to use crossed polarizing filters. Still, the subject is short scale and one must set the white and black points.
Now, to discuss your posted shots. If anything, your posts confirm my initial assertion, since you are correcting post processing and not by changing exposure in the camera. The corrected images are from the same raw expsosures with postprocessing. By the way, if you post your screen shots as PNG, you will eliminate the artifacts around the text.
I put some links of images to explain my point since we still talk about something else. (cannot insert pics via adobe).
http://hajes.org/img/acr/cairngorn.jpg
Brilliant example of screwed up "I have been there" photography. Exposed not very well and at worst light possible. Must go there once again and fix my incompetence.
http://hajes.org/img/acr/cairngorn2.jpg
Cairngorn is short scale because of atmospheric haze. There is no way to correct that with in camera exposure, but you could have exposed more to the right. Nonetheless, you have captured the whole dynamic range of the scene and exposing to the right would only improve the signal:noise. You had to use the exposure and black slider to set the white and black points, which only confirms what I said in my previious posts.
somehow "fixed" previous image. just for fun and learn PS CS4.
http://hajes.org/img/acr/hrad.jpg
overexposed image at first glance by untrained eye.
Hrad is a high dynamic range scene with blown highlights. Your use of the exposure control to bring down the highlights darkens the rest of the image to an undesirable degree. It would have been better to use recovery to tame the highlights. A better approach might be to deveolp for the highlights and shadows separtely and merge the results as shown below. Again the correction is in postprocessing. There would be no way to do that with a camera exposure. The use of +1EV in ACR in HRAD3 only worsens the highlight clipping.
http://imagingpro.wordpress.com/2008/12/03/expanding-the-dynamic-range-of-a-single-raw-fil e/
http://hajes.org/img/acr/hrad2.jpg
same image with 1EV extra without of any detail loss. miracle of digital sensors.
http://hajes.org/img/acr/hrad3.jpg
final image. it is just for web, so no bother about burned sky...
http://hajes.org/img/acr/tunka.jpg
again, overexposed image at first glance by untrained eye. we don't care about clipped shell in the left middle of image. it is not main interest of pic...
http://hajes.org/img/acr/tunka2.jpg
..and we again get 0.50EV extra which corrects clipping.
I don't see any evidence of overexposure. The highlights are well short of clipping and the shot is grossly underexposed--not exposed sufficiently to the right. Nonetheless, the full dynamic range of the short scale scene has been captured and the shadows are well above clipping.
In case some will wonder about weird setting of ACR. It is just for web and I still don't know all tricks of PS. Furthermore, I prefer to spend time in nature rather than in front of computer.
The settings of ACR are indeed wierd. Thomas Knoll recommends setting the highlights with the expsoure slider and the midtones with brightness. An alternative way of doing this, introduced with Lightroom, would be to set the midtones with exposure and control the highlights with recovery. A black point setting would likely be required as well. Again, no way to do that with an in camera expsoure, validating my previous assertion.

Histogram LR vs Camera Raw

Why the histogram between Camera Raw and lightroom is different? When I make the black point and white point, the point of clipping, result different for the the same photo with same value.
Let me know
Thank's

Lh 5.7 and CR 8.7!!!! How you can see same value but different result on histogram clipping

Camera data. Histogram and light meter

I'm trying to find info on how to tap into data from the iPhone camera. I want to develop an app that uses histogram data and to build a light meter. Can anyone help me out?

You can build your own histogram from any image. I very highly doubt you'll be able to construct anything even remotely resembling an accurate light meter as the camera's driver and/or firmware most likely already has one that is continually making adjustments before you ever get any data at the application level.

Histogram handling of camera-generated DNG files

I'm using a Ricoh Caplio GX100 camera which produces generic DNG files. Is it because Aperture doesn't officially support this camera that the main histogram doesn't display the separate RGB channels, regardless whether set to Auto Levels Separate?

Dennis-H wrote:
Is there a utility that can verify the integrity of a suspect DNG file?
his page explaines how to do that usingAdobe DNG Converter:
http://www.dpbestflow.org/node/382

Using the histogram and RGB values in camera raw

This question was posted in response to the following article: http://help.adobe.com/en_US/photoshopelements/using/WS287f927bd30d4b1f5548d97812e28a69a90- 7ff4.html

K so no one has been able to help me. When I open a raw image all my highlighted areas are pink. I cannot turn it off by clicking the little triangle. I'm losing my mind. I've been trying to figure this out for months!

Lightroom's 4 color "spaces"

I’m working on designing an advanced photography course. This course makes use of Lightroom and Photoshop in the photographic workflow.
I’m learning and researching myself as I go along, and I feel I have reached a ceiling on what I can work out from the sources at my disposal thus far.
So I am turning here for help.
I am trying to clarify how tones and colours are affected from the actual scene through to the printed page. This might seem like overkill to some. However, there is a lot of misunderstanding and confusion, not to mention heated discussions amongst photographers about these issues. I’m experimenting with metering and colour / tone targets and my calculations are only meaningful if I understand how tones and colours are affected at every stage of the workflow.
Here’s how I understand it:
There are 4 (sort of) Colour “spaces” in Develop where a real-time dynamic preview of an image is rendered
1.       The “viewing space” (ProPhotoRGB Chromaticity co-ordinates, sRGB gamma)
2.       The “computational space” (ProPhotoRGB chromaticity co-ordinates, linear gamma – “MelissaRGB”)
(Martin Evening’s Lightroom 3 book published by Adobe press - Appendix B, section on color space page 628-632)
Below that, things get a little fuzzy. According to Jeff Schewe (Real World Camera RAW for CS5, page 32) there is a sort of
3.            “Native Camera Space” and of course there is the
4.            RAW data in the file on disk.
So to generate the dynamically rendered preview, the image goes through the four “layers” as follows (from bottom to top). This is almost certainly flawed, but one has to start somewhere when trying to work things out :-)
1. The RAW file is read from disk. Colorimetric interpretation is performed using a camera profile (e.g. Adobe Standard for whatever camera it is you are using). This process puts the image data into “Native camera space” (“Plotted” onto CIE XYZ with D50 white point)
2. In “Native camera space, the scene white balance (as selected by user, guessed by Lightroom or reported by camera) as well as additional camera calibration panel matrix tweaks “informs” the colorimetric conversion into Lightroom’s “computational space” e.g. Melissa RGB. The colorimetric definition of camera RGB primaries and white is re-DEFINED. The demosaicing as well as chromatic aberration corrections are performed in “native camera space”
3. Almost all image processing calculations occur computationally in the “MelissaRGB Lightroom computational space”
4. What is displayed on the screen, however, has an sRGB tone curve applied. This represents the “viewing” space. The histogram is generated from this and the RGB colour percentage readouts are generated from this as well. In addition, some slider controls from user input are weighted back through the tone curve into the computational space below.
Could someone from Adobe kindly help me to clarify the steps? Eric are you reading this? :-)
Thanks in advance

Sandy - Thanks for the link. The spreadsheets you posted on your site is quite helpful.
Jao – I think what you said goes to the heart of what I am trying to achieve here: “Photograph a grey target at the exact same exposure with the exact same lighting but with different cameras and you'll end up with different values in the raw files” Which is why I encourage photographers to experiment with their cameras in order to understand exactly how the camera will respond in the heat of a real shoot. Set up a scene; take a picture, open in Lightroom. What is clipped and why? Use a reflective spot meter. Repeat. Use a hand held incident meter. Repeat. How much can you reliably recover? Are you happy with what your meter considers the mid-point (and what you set your exposure for on the camera) or do you need to compensate? Just how much latitude do you have between what your camera histogram shows as a blown out highlight and what Lightroom shows as a blown out highlight. This relates to tone. I could go on with more examples, but by now, I am (hopefully) making more sense.
I’m merely trying to clarify that which is already public in order to form a coherent mental picture. And by mental picture I do not mean an accurate representation of the minutiae and maths involved. Think of a subway map. It represents a bird’s eye view of a transportation system in a logical fashion, yet it bears almost no resemblance to the cartographical reality of the physical topography. I really don’t care where the tunnels go, how they were dug, how they are maintained or where they twist and turn. What I AM looking for is a logical (not physical) map. This map tells me where the different lines begin and end, and where I can change from one line to the other. The most important quality of the map as a whole is that it provides context. You can tell, at a glance, how different lines interact with each other and even how it links to other entities such as bus stations or public landmarks.
As many have rightfully pointed out, I should not have to care about the maths/secret sauce/internal calculations. And I don’t. In addition, I am a very happy Lightroom user and I am very comfortable using it. I know what a user needs to know to get his picture from A to B. There is no shortage of information on how to accomplish that.
It might help if I illustrate what I am trying to do below:
Please excuse the low resolution, the maximum height allowed for upload is 600 pixels. The picture below goes on the bottom left of the "layer" picture above.
Even though there are certainly many mistakes in my diagram, this is a helpful visualisation. I derived this diagram from publicly available information. As the subway map, this is a logical (not physical) representation that provides context in a visual form. With a little help from people like Eric I am sure I can correct and expand it. The net result is an enhanced understanding of Lightroom and ACR and where it fits into the photographic process, both in terms of tone and colour.
I am not posting the entire chart here since I am not even certain that a 4 “layered” representation is an appropriate logical representation. I posted the spine of the chart with the 4 “layers” and one part that elaborates on the colorimetric interpretation between the two bottom layers. Comments and corrections are welcomed. And I am convinced that this can be accomplished without divulging anything confidential.

Exposure to the right results in different TRC than normal exposure

Exposure to the right is advocated by most experts to improve tonality and dynamic range. On the Luminous Landscape a photographer noted that ETTR all the way to the right followed by negative exposure correction in ACR produces a different image than is produced by normal exposure, and that he preferred the latter image.
Luminous Landscape Thread
Most responders to this post postulated that, since ACR is operating on linear data, underexposure by 1 EV followed by a 1 EV boost in ACR would produce the same results.
I had some exposures of a Stouffer step wedge. The first was exposed so that step 1 has a pixel value of 250 when converted with ACR at default settings into aRGB. This is exposed to the right as far as possible. A second exposure placed the same step at 221, and this step was brought back to 250 in ACR, which required an exposure compensation of +1.05 EV.
If you compare the resultant images in Photoshop using the difference blending mode, the differences too dark to make out on the screen, but can be detected with the eye dropper. In this image, normal exposure to the right is on top, and the difference between normal exposure and underexposure followed by a boost of 1 EV in ACR is shown on the bottom.
The different resulting tone response curves are better shown by Imatest plots of the two images. As is evident the TRCs are different, contrary to my expectation. Comments are invited.

The ETTR Myth
ETTR is short for expose to the right. Some folks have promoted it as a replacement for traditional exposure metering. The premise is that you can validate camera metering by simply reading the histogram in the cameras preview window.
Unfortunately, it is based on some basic misunderstandings about digital photographic technology. The first misunderstanding is the premise that each bit level in a digitally encoded image represents an exposure stop. The second misunderstanding is the premise that all digital cameras capture light in a perfectly linear fashion. The third misunderstanding is the premise that the histogram represents the raw image data captured by the camera. I will briefly address each of these.
Any correlation between exposure stops and digital bit levels can only be accidental at best. The total exposure range in a scene or an image is correctly known as the dynamic range. The dynamic range of digital cameras is wider than most folks assumes and usually equal to or better than film or paper. It can be defined in terms of tone density, decibels, or exposure stops. It is a function of the optics and sensor electronics in the camera. The few cases where an accurate range is provided by the vendors, it varies from 8 to 12 f/stops.
The image data is converted from analog measurements by the analog/digital (A/D) circuits early in the capture. This can wind up as an 8-bit, 12-bit, 14-bit, or even 16-bit digital value depending on the camera and its user settings. It is simply a number that has been digitized. Any correlation between bits and exposure levels is pure speculation, end of subject.
Second, the digital capture of light is not strictly linear. It is true that the silicon sensor itself will capture light in a very linear fashion. But this ignores reciprocity at the toe and heel of the extremes, the quantum efficiency of the substrate, and most importantly it ignores the optical filters in front of the sensor. If the color filter array were linear it would be impossible to reconstruct colors. And these are not the only optical filters in your camera. Then, the A/D circuits have gain controls based on the current ISO setting. And some A/D circuits perform some pre-processing based on the illuminant color temperature (white balance) and limited noise reduction based on the ISO setting. The point is that there are many steps in the pipeline that can introduce non-linearity.
Finally, the image in the preview window has been color rendered and re-sampled down to a small size. This is the data shown in the histogram. The camera can capture all colors in the spectrum, but the rendered image is limited to the gamut of an RGB color space. So, in addition to exposure clipping the histogram will include gamut clipping. This is also true for the blinking highlight and shadow tools. This might imply an exposure problem when none exists. There is no practical way to map all the data in a raw image into a histogram that you could use effectively in the preview window.
If you capture an image of a gray scale chart that fits within the dynamic range of the camera, at the right exposure, you can create a linear graph of the raw data. But if you underexpose or overexpose this same image, the graph will not be linear and it is unlikely that software will be able to restore true linearity. End of subject.
If you typically shoot JPG format, the histogram will accurately represent the image data. But clipping can still be from either gamut or exposure limits. If you typically shoot RAW format, the cameras histogram is only an approximation of what the final rendered image might look like. There is a significant amount of latitude provided by the RAW image editor. This is probably why you are shooting RAW in the first place.
So, in closing, I am not saying that histograms are bad. They are part of a wonderful toolkit of digital image processing tools. I am saying ETTR is not a replacement for exposure metering. If you understand what the tone and color range of the scene is, you can evaluate the histogram much better. And if you master traditional photographic metering, you will capture it more accurately more often.
I hope this clears up my previous statements on this subject. And I hope it explains why I think ETTR and linear capture are based more on technical theology than on technical fact.
Cheers, Rags :-)

Canon 1D MkIV images too dark

Hi there
Having a problem here. The RAW images from my Canon 1D Mark IV come in a stop too dark!
When I open them, they lookfine; a second later they switch to a too-dark version. I am using Camera Standard, and no other adjustments.
It's not just visual: the histogram of the opened file is shifter a stop to the left compared to the same phoito's histogram on the camera.
Any ideas? This is a major issue for me since I rely on both the 1D MkIV and Lightroom to make a living...
Many thanks
Michael
www.michaelwillems.ca

Hi M, the question is simple, but the answer is complex. I'll provide an example to try to illustrate. The attached image is a downsampled version of a JPEG from the 1D Mark IV. It's a test picture of a color chart. I've drawn a red circle around the 2nd gray patch in the 4th row. When I take a picture with the 1D Mark IV zoomed into this patch at this exposure, I get a histogram all the way to the right. And indeed, when I open the file in any image editor (e.g., Photoshop, or DPP), and use a color picker / eyedropper to sample the values, the average value of that patch is (255,255,255). So this is like in your example when you say you look at the histogram (e.g., in DPP or on the camera LCD) and it's all the way to the right. In other words, the histogram effectively says this patch is clipped to the max value.
However, if we look at the average raw values in this example for that patch, they are actually (on an 8-bit scale) about (72, 209, 187). In other words, the actual camera-recorded raw values are still pretty far away from clipping to 255. (I should also mention that the camera-recorded raw values aren't white-balanced, which is why the green value is much higher than the red & blue values, above.)
So you can see there is a discrepancy between the camera-produced JPEG and the actual raw values. In this example, the camera histogram and JPEG values indicate a clipped patch at (255,255,255). If you are going by that histogram, then you would conclude reasonably that this patch is overexposed and clipped -- when actually it is not.
More generally, there are always discrepancies / differences between camera-recorded raw values and the histogram shown on the back of the camera (as well as the JPEGs rendered by the camera). This isn't error. This is preference. Cameras and software apply "preset" exposure and tone curve processing (and possibly sharpening, noise reduction, etc.), and the histograms you see on the back of the camera are based on those presets (not the actual raw data). This is why your histogram on the camera will change depending on your in-camera settings of white balance, tone curve, contrast, etc.
There is nothing wrong with the 1D Mark IV. Many Canon DSLRs currently leave a lot of highlight headroom, i.e., when metering they will be conservative on the highlight side, and expose a little less. As I recall (don't have my full notes in front of me), the 1D IV spot meters about 3.5 stops below the actual clipping point. In other words, if I had spot-metered that gray patch in the attached example, and started with the meter needle in the middle, I could then increase the exposure by about 3.5 stops before I actually clip that patch. That's quite a lot.
To summarize: you have to be careful when interpreting camera histograms. In many cases, it is easy to interpret that something is clipped when in fact it is not. If you see a histogram that appears bunched up to the right, the tendency is to decrease the exposure, and therefore make the histogram move to the left (so you aren't overexposing). In reality it is possible the original exposure was fine (without overexposure), and all that's happened is that now the image is even more underexposed.

Aperture 3 and underexposed RAW conversion

I run Aperture 3.03 with CameraRAW 3.3 and OS 10.6.4. I use a Nikon D300 and download as referenced images into Aperture via a SanDisk card reader.
Somewhere around the time I upgraded to CameraRAW 3.3 and OS 10.6.4 (not exactly at the same time but within a short period of time) I have noticed in Aperture 3 that my newly imported images appear significantly underexposed. In fact, I can watch as a batch of properly exposed imported images darken one after the other as they are processed. This has never been a problem before. At present I have resorted to manually adjusting the images in Aperture, usually requiring anywhere from 1 to 2 full stops of exposure adjustment to make a correction. Even with lift and stamp this is a very tedious process with 200 to 300 images at a time.
I expose my images with care and always view the on-camera histogram to check against over/under exposure.
Am I missing something obvious that i should be doing differently? Could it be my camera?
Any thoughts would be greatly appreciated.
Bob

First thing to look at is the histogram, you say that it is correct in camera. It should look much the same in Aperture. You also say the images darken, this is normal behavior as they get processed. If they look ok on the histogram the are ok. Raw can record a little more of the light and dark areas of a scene, than is represented on the histogram and these areas can be pulled in with adjustments.
Any adjustments that you want to make as the images are imported is easy. Presets allow any adjustments to be applied during import. Make the adjustments to a typical image, go to Presets at the bottom of the drop down list is Save. Click and these adjustments can be selected on the Import Panel Presets and applied to every image as it is imported.
If using the Lift and Stamp, select the images to be adjusted, with the Shift and Apple (command) key, ensure the Primary only is not on, in the bottom right corner of the Viewer. Allthe images get processed one after another automatically.
The exposure is what it was at the time the image was captured. Aperture cannot change that.
If a preset has been darkening the images the last paragraph will solve that.
Allan

ACR Overexposure with Nikon D3

Exposure to the right (ETTR) is a standard technique that requires placing of the image highlights just short of clipping in the raw file. Such exposure is often judged by the histogram or blinking highlights in the camera preview of the image, but is best determined by examining the raw file, since the camera preview is derived from a JPEG image to which the camera settings (white balance, tone curve, etc) have been applied. When one brings the raw file into Camera Raw, the white balance setting is applied, but the other camera settings are ignored. If the ACR histogram shows clipping of the highlights and a negative exposure adjustment is needed to recover them, this usually indicates that the image was overexposed. However, with the D3, the default ACR tone curve places the highlights too high and clipping occurs in the rendered file even when the highlights in the raw file are intact.
I exposed a Stouffer step wedge so that step 1 was just short of clipping with the Nikon D3 using 14 bit NEF and the results are shown in an Imatest plot using the built in DCRaw converter. The results are linear as expected.
http://bjanes.smugmug.com/photos/271579079_BGUhM-O.png
Next, I split off the the green1 channel of the raw file with Iris (a freeware astronomical program)and examined the results in ImageJ (a freeware program from the National Institutes of Health). This plot shows that step 1 is just short of clipping:
http://bjanes.smugmug.com/photos/271460382_RqUdu-O.gif
and this is further confirmed by the histogram:
http://bjanes.smugmug.com/photos/271460379_qwjtR-O.gif
However, when the file is brought into ACR, with the default tone curve, the highlights are clipped as shown:
http://bjanes.smugmug.com/photos/271460363_jMYHL-O.png
and -0.6 EV of exposure compensation is required to bring Step 1 in range:
http://bjanes.smugmug.com/photos/271460357_vDqYZ-O.png
Nikon Capture NX renders the highlights of this file correctly.:
http://bjanes.smugmug.com/photos/271569001_ZJwqX-O.png
The conclusion is that the default ACR tone curve for the D3 is too "hot" and indicates overexposure when none exists.
Next, here is the camera histogram of the properly exposed image. The histogram shows some clipping which is not really present in the raw file and which is eliminated by exposing 0.3 EV less. The conclusion is that the camera histogram is slightly conservative.
http://bjanes.smugmug.com/photos/271460374_mRjof-O.png
http://bjanes.smugmug.com/photos/271460388_WDMpW-O.png
The blinking highlight display is even more conservative and indicates overexposure by 0.6 EV:
http://bjanes.smugmug.com/photos/271460368_iFDsP-O.png
For optimum results with ETTR, it is best to perform your own tests to determine the accuracy of the in camera histogram and blinking highlights so that these aids may be used for optimum exposure. Since the camera tone curve affects the results, it is important to use the same tone curve each time. Furthermore, one should be aware that the ACR default tone curve is too hot and that one does not necessarily have to reduce exposure when a negative exposure compensation is needed to bring the highlights into range. This ACR overexposure has been noted by others, but I do not know if it occurs with all D3s. If so, then the default tone curve should be revised by Adobe.
http://www.nikonians.org/forums/dcboard.php?az=show_topic&forum=147&topic_id=53935&mesg_id =53935&page=2

Lawrence,
> How do you open a DNG that would be different than .nef?
The difference between the native raw and the DNG (in this case created by Adobe's DNG converter) is not in the raw data itself but in the metadata; BaselineExposure is a creature of the converter (and if the converter interprets the raw data this way, then ACR too is doing it this way).
I mentioned the DNG format, because *in the DNG file* (as metadata) the adjustment can be seen *explicitely*, in contrast to ACR's processing, which is lying about it: the "Exposure" slider is at 0, despite having adjusted the intensity. (Note, that ACR does not show the adjustment with DNG either.)
> Are you suggesting that converting a suspicious file having highlight clipping might be saved by converting to DNG?
There is no need to convert the file. The data is not lost - it is the same, as if you process a well-exposed image and adjust "Exposure" by (in this case) 1/2 EV: some pixels may become clipped. You can counter this several ways (beside by resetting the exposure adjustment), for example by Recovery (even though there is nothing to recover here, for nothing was lost in the first place), Contrast, etc.
The issue is not, that ACR woud lose image data, but
1. the auto-adjustment is not justified in this case (it is nonsense, that a Nikon D300's exposure should be adjusted to some imaginary "standard", even if that causes loss of part of the image),
2. it can be destructive if the user is not versed enough,
3. it is not indicated explicitely.

Nikon D700 Opens .6 to 1 stop over exposed in ACR 5.2

My D700 histogram shows the pix to be properly exposed but when I open them in ACR all images are .6 to 1 stop over exposed. While I can reduce exposure in ACR I have not had this problem in CS3 with my D100 & D200 cameras. What's the fix?

>The histogram you see on your camera is NOT based on your raw image directly, but on the JPEG preview created by the camera's built in software and to which adjustments are automatically applied.
What Ramón says is quite true, but you can compare the raw histogram to the camera histogram, With the Nikon D3 set to Adobe RGB and the standard Picture Control, I have found that the camera histogram and blinking highlights are slightly conservative but are generally reliable indicators of the raw histogram. Since the D3 and D700 have essentially the same image processing, I would think that this would also be true for the D700. (since inline images are not allowed in these forums, the message is hard to read since you have to click on the link to see the image. Ramón has figured out a way to have thumbnails with Pixentral, but I have not found a way to do this with my site, Smugmug)
Bill Janes, "ETTR and ACR" #3, 12 Nov 2008 6:37 am
One must be aware that the black and white camera histograms are luminance histograms which are strongly weighted towards the green luminance, whereas the ACR histogram is an RGB histogram and is similar to the color histograms of the camera superimposed on one another.
Both of these histograms reflect white balance. The red and blue channels may appear blown on the camera histogram or ACR histogram when in fact these channels are far from clipping in the raw file. Some users load a UniWB into the camera to get a better approximation of the raw channels.
Since the widest space in the camera is aRGB, the camera histogram may show saturation clipping with intact raw channels. It would be nice if Nikon would also provide ProPhotoRGB as a color space.

Camera histogram vs LR histogram

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