Exposure Curves in ACR

Using ACR (CS3), I find that I can get decent expansion of dynamic range by using one raw file and creating 3 different files from it by varying the exposure setting: 1 under-, 1 over, and 1 normal exposure. Then of course those 3 files are composited in Photoshop using the usual techniques of either masking or the HDR plug in.
But I would like to see an additional curves dialogue that affects exposure. Boosting shadows in ACR’s current tone curve dialogue does not, for example, bring out the hidden detail that really is present in the raw file. The affected areas will of course be brightned but flat, often monotone, while compositing 3 different files with differing exposure settings of that same raw file would bring out all the recorded detail.
Does Adobe have plans to make an exposure curve dialoge box?
Thanks

The Exposure slider is indeed in stops (-4 to +4 EVs) but you will find that it isn't completely equivalent to changing the exposure in the camera due to other settings in ACR also coming into play, although you may be able to find a set of brightness/contrast/black-point/toning-curve/camera-calibration that come close.

Similar Messages

Exposure Adjustment in ACR

I am conducting some camera & lens tests and would like to hold the shutter speed at a constant and vary the exposure over an approximate 5 stop range of apertures. I'd like then to correct the exposures as closely as possible in ACR. Are the values shown for the exposure slider in stops or something other? In the end with respect to exposure, contrast and brightness I would like all of the images to very similar without repect to sharpness.

The Exposure slider is indeed in stops (-4 to +4 EVs) but you will find that it isn't completely equivalent to changing the exposure in the camera due to other settings in ACR also coming into play, although you may be able to find a set of brightness/contrast/black-point/toning-curve/camera-calibration that come close.

Levels, Exposure, Curves - another explanation attempt

The exposure slider in Aperture does pretty much the same as moving the right bottom sliders in Levels. One difference is that one naturally can move the right slider in levels only to the left. The exposure slider can be moved in both directions.
The brightness slider does the exactly the same, except that it acts on the left bottom control in Levels. The contrast slider acts on both the right and left control.
In general, Levels is a much more powerfull tool [than the Exposure section] but can be trickier to use (and it is easy to spoil an image by making it look anatural). Its sliders can create much more drastic changes, e.g. extremely high contrast. And by offering midtone and quartertone controls, different tonal ranges can be adjusted differently. By moving the top sliders the these controls can be moved to any point in the tonal range.
When moving the right or left slider in Levels to the start of the histogram (to create pure blacks and whites), particularly when moving them quite a bit, one often might get better results by doing this separately for the three channels than on the luminance channel.
Generally, I have the impression that Exposure/Brightness/Contrast do a better job at balancing the three colour channels than the levels adjustment set to Luminance to maintain a natural look.
Comparing with the Curve tool (in e.g. Photoshop), one can state that levels and curves do exactly the same, the top controls on the diagram in levels in Aperture are the output of curves (y-axis) and and the bottom controls in Aperture are the input of curves (x-axis). The level controls in Aperture, however, 'only' have five control sliders at the bottom and only three at the top (and none at endpoints there).
An attempt to explain why all controls do more or less the same:
Take a B&W image (that makes things easier to understand). Any global image manipulation does nothing but remap luminence values. Every lumininence value in the original image gets translated into a value in the output, e.g., adding 20 (on the scale 0-255) to all brightens an image (probably not in a very smart way). This remapping is given by a functional relationship that can be illustrated by the curve in Curve tool. But there a lot of ways to represent that functional relationship, with levels being just another one (and one that I find more intuitive).

The exposure slider in Aperture does pretty much the same as moving the right bottom sliders in Levels. One difference is that one naturally can move the right slider in levels only to the left. The exposure slider can be moved in both directions.
The brightness slider does the exactly the same, except that it acts on the left bottom control in Levels. The contrast slider acts on both the right and left control.
In general, Levels is a much more powerfull tool [than the Exposure section] but can be trickier to use (and it is easy to spoil an image by making it look anatural). Its sliders can create much more drastic changes, e.g. extremely high contrast. And by offering midtone and quartertone controls, different tonal ranges can be adjusted differently. By moving the top sliders the these controls can be moved to any point in the tonal range.
When moving the right or left slider in Levels to the start of the histogram (to create pure blacks and whites), particularly when moving them quite a bit, one often might get better results by doing this separately for the three channels than on the luminance channel.
Generally, I have the impression that Exposure/Brightness/Contrast do a better job at balancing the three colour channels than the levels adjustment set to Luminance to maintain a natural look.
Comparing with the Curve tool (in e.g. Photoshop), one can state that levels and curves do exactly the same, the top controls on the diagram in levels in Aperture are the output of curves (y-axis) and and the bottom controls in Aperture are the input of curves (x-axis). The level controls in Aperture, however, 'only' have five control sliders at the bottom and only three at the top (and none at endpoints there).
An attempt to explain why all controls do more or less the same:
Take a B&W image (that makes things easier to understand). Any global image manipulation does nothing but remap luminence values. Every lumininence value in the original image gets translated into a value in the output, e.g., adding 20 (on the scale 0-255) to all brightens an image (probably not in a very smart way). This remapping is given by a functional relationship that can be illustrated by the curve in Curve tool. But there a lot of ways to represent that functional relationship, with levels being just another one (and one that I find more intuitive).

Why curves in ACR acts so different in comparison on other programms?

Similar question I made in LR forum but realize that in here more suitable place.
"Does anybody knows, why Adobe made adjustment of curves in lightroom so different in comparison of curves Photoshop? I mean not of adjustment method, but colour shifts. Darkening by curves in LR makes skin tones very dirty yellow-orange, while photoshop's tends to red, and when lightening in LR skin tones becomes _unpleasant_ pink-orange while in PS becomes acceptable uniform yellow hue. This I checked on the same file (tif). Differenses of colours shifts (LR vs PS) happens even while adjust other sliders, such as brightness and contrast, for example"
As to my taste and preferences, I dont like LR behaviour.
ps. In attachment you can see huge differences. Question is why? For what reason? And will I got this in future versions?
pps. camera profiles and untwisted variants of them have not relation to this behaviour.

>Sounds like you're using and comparing other image editors as a profiling device for your camera that just happens to make your edits fit your taste in color. That's not a recipe for consistency.
Simply I often used curves in PS and when LR has appeared I expected same behavior of curves. I have mistaken.
I see that many PS actions like TRA or Kubbota`s uses this property of PS curves (skin tones darkening shifts to red, lightnening shifts to yellow) to make photos great/pop looking. But I do not want to use PS. Again it requires making aside tiff.
>You're going to have to do some adjustments on every image.
Yes. But most light still incandescent: concerts, private rooms, cafes.
>You might try quick adjustments to the orange and/or yellow sliders in the Hue panel in LR's HSL panel. That's what I have to do to get that reddish hue to skin.
Yes, I do this, but when I touch curves on opposite side I have to adjust hue sliders again. This is not very quick. But for this case I have made many presets of HSL sliders for different curves and simply apply them
>Why not profile the camera shooting Raw under these lights using an X-rite color chart and the DNG Profile Editor or some other camera profiling package?
I will repeat again (do not take offence): Curves still act the same way in spite of right colors achieved by this calibration.
>They seem to lean toward a reddish rendering with better definition out of the box which isn't accurate but is pleasing.
I will read about this technology. Thank you.
In case I have to get correct/right colors now I use self made icc profiles by X-Rite Colormunki device and freeware profiling software (argyll) and custom made color checker with at least 108 patches instead of standard 24. But I have to follow these conditions: 1. Same light. 2. Same settings in developing software (that means I cannot touch any curve, contrast, hue and other sliders therefore why to use LR in general? ). 3. Developing program must operate with icc profile (sadly LR can't do this).
Some addition information about right and pleasant colours: Now I have Canon`s SLR camera, but very love nikon`s colours (camera profiles). By dng profile editor I have applied for my cr2 files nikon's camera profiles and have got truly nikon`s colors without buying nikon camera. Colours exactly the same as in Capture NX in default settings until I start to adjust contrast, curves in LR...
>Also you might try Lightroom 3 Beta which has a new preview rendering algorithm which might include the color effect you see in Photoshop.
I have tried LR3 for a long time ago but see it still have same algorithm of curves and contrast. May be developers add in final release some color manage preferences for choosing working colour space or so.

ACR - exposure slider

I notice when I use the exposure slider in ACR and back off when I see just the initial red clipping my image is way way over exposed... Anyone else experience this problem?

The clipping highlights are only an indication. Your best exposure will probably have some elements of red and blue; so trust your own eyes.
Use the recovery slider and black slider if necessary.
The vibrance slider is also useful - it will enhance subtle colors (e.g. sky and leaves in a landscape) without blowing out more saturated colors e.g. (red and orange flowers)
Have a play around with all the sliders and experiment - no permanent changes are made to raw files or jpegs in ACR.

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 :-)

ACR and dynamic range tests

I have been looking at dynamic range tests on dpreview.com for different cameras. I'm particularly intrigued by the "RAW headroom" graphs. They have things like "ACR Best: Exp. -0.85 EV, Shadows 0, Bright. 70, Contrast -25, Curve Linear" (Pentax K10D), "ACR Best: Exp. -1.3 EV, Shadows 0, Bright. 70, Contrast -50, Curve Linear" (Canon 30D) "ACR Best: Exp. -1.0 EV, Shadows 0, Bright. 70, Contrast -50, Curve Linear" (Canon 400D). The "RAW ACR Best" curves for all these cameras are very different, and I don't think I understand their real meaning, so here are a few questions:
- What is a "linear curve" in ACR? Does it mean no curve at all is applied to the RAW data, and so what we see is the actual sensor response? Or, does ACR apply a standard curve to RAW data from all cameras, even when a "linear curve" is selected? Or even yet, are there different default curves (even with "linear curve" selected) for different cameras in ACR, and what implications would this have when comparing graphs from different cameras?
- Since these cameras have most likely been processed with different versions of ACR (since they were released at different times), could ACR's algorithms and defaults have been changed in any way that might prevent these tests from being readily comparable? For example, the noise reduction and highlight recovery algorithms might have been improved in the latest versions of ACR.
Thanks,
Marcos

>- What is a "linear curve" in ACR? Does it mean no curve at all is applied to the RAW data, and so what we see is the actual sensor response? Or, does ACR apply a standard curve to RAW data from all cameras, even when a "linear curve" is selected? Or even yet, are there different default curves (even with "linear curve" selected) for different cameras in ACR, and what implications would this have when comparing graphs from different cameras?
ACR will not give you the actual sensor response with no white balance or gamma encoding; for this purpose you need a specialized program such as DCRaw. If you convert into sRGB or aRGB, the image is encoded with a gamma of 2.2, whereas a gamma of 1.8 is used for ProPhotoRGB.
If you want to linearize the tonal response in ACR you can set the sliders on the basic tab to zero (Exposure, Brightness, Contrast to and Shadows). Curves was added in ACR ver 3.X and you should also set the curve to linear. The Medium and Strong Contrast in the curves tab adds to the Contrast slider in the basic tab, and I think that the two were not merged for reasons of backward compatibility. In all cases, the resulting image is gamma encoded. To learn more about these controls, I would recommend Bruce Fraser's Real World Camera Raw for PSCS2 book. The Exposure and Black sliders set the black and white endpoints respectively. The contrast control applies an S curve around the midpoint, which is set by the Brightness control (see p 81). Jeff Schewe is revising the book for PSCS3 due out shortly.
Dynamic range is limited by the noise floor and improvements in noise reduction in the current version of ACR could affect the results. Phil's dynamic range measurement uses highlight recovery with the Exposure slider (negative values). ACR 4.1 also has the Recovery slider, but he apparently does not use this control.

ACR Defaults and Dynamic Range

The tone curve in ACR has a profound effect on the dynamic range of the rendered image, and often this is not appreciated by users. To demonstrate the effects of the tone curve on DR, I photographed a Stouffer step wedge with the Nikon D3 and rendered the image into a TIFF with various tone curves and determined the resulting dynamic range with Imatest.
Here is the target rendered with the ACR defaults for this camera, which include a black point of 5 (downsampled and shown as a JPEG):
http://bjanes.smugmug.com/photos/422699368_FRdKT-O.jpg
Shown below is the resulting characteristic curve as determined by Imatest along with the DR and other data. The total dynamic range is only 7.64 stops. This low DR results from the default black point of 5, which rolls off the darker tones as shown on the graph.
http://bjanes.smugmug.com/photos/422697342_tnUFo-O.png
By setting the black to 0, the total DR is increased to 12.3 stops and the useful photographic DR according to various quality levels is shown.
http://bjanes.smugmug.com/photos/422697338_5e8pv-O.png
One can also use a linear tone curve by setting all the basic settings to 0 and the point curve to linear.
http://bjanes.smugmug.com/photos/422697332_u59B5-O.png
For convenience, the tone curves are shown together here.
http://bjanes.smugmug.com/photos/422697328_26BFV-O.gif
One might wonder why Adobe chose a default black value of 5 for the D3, since it severely limits dynamic range by rolling off the blacks. The probable answer is that the full DR can not be reproduced on screen or in print without using a tone curve that would give the image a flat and unattractive appearance. Note that the darker steps of the Stouffer wedge are not distinguishable on the screen but differences can be noted if one measures the values with the eyedropper in PS. The default setting of 5 rolls of shadows which would not be reproduced and enhances contrast in the remaining image.

>Why? Real World Camera Raw is platform agnosticaside from the fact that most all of the images contained in the book happen to come from cameras Bruce and I had/have and those are Canons. To the best of my knowledge, there is nothing in Camera Raw that is camera model dependent except for the DNG Profiles and the baseline demosiacing and noise reduction which vary camera by camera. Why should I care about the Nikon D3 specifically?
In 35 mm style dSLRs (which I would venture to say are used by the vast majority of ACR users) Nikon and Canon are the two major brands. One thing that is camera specific is the baseline exposure offset that ACR uses for these cameras. For the Nikon D3 (and other recent Nikon cameras), ACR uses a baseline exposure offset of +0.5 EV. If you don't know this and try to expose to the right as much as possible, the histogram will appear overexposed in ACR when in reality the channels are far from clipping.
This is demonstrated in the following screen capture using ACR defaults with an Exposure value of 0. The highlights of the target appear blown.
http://bjanes.smugmug.com/photos/423897106_wvzqw-O.png
They also appear blown using the new beta profile, which does not take the baseline exposure offset into account.
http://bjanes.smugmug.com/photos/423897066_xeHoi-O.png
Looking at the raw histogram with Rawnalize, we see that the channels are not blown:
http://bjanes.smugmug.com/photos/423898181_md3kC-O.png
And here are the actual raw values for the red, green and blue channels (highlighted) of Step 1:
http://bjanes.smugmug.com/photos/423901972_MguxL-O.png
The raw headroom in each of the color channels (as shown in the raw histogram) also has something to do with the amount of highlight recovery that is possible. I would think that these considerations would be of inerest to the readers of your Camera Raw book.

ACR and tiff file

I convert with a third party tool some images in tiff (linear gamma) and I want edit them in ACR.
Is better keep them in linear gamma or is better convert them to a gamma corrected color space before import them in ACR?
Internally ACR works always in linear gamma even with jpeg, right?
Marco

> my first edit in PS on linear image is tweak the exposure with a linear curve. Make the exposure slider in ACR the same thing?
These are vastly different.
1. The "exposure" adjustment in ACR increases the raw pixel intensities, like increasing the exposure would have done. This is a linear adjustment
b before the non-linear mapping.
Consequently, the linear adjustment becomes non-linear in the converted data.
Try it out: increase the exposure in ACR by one stop, then two stops, etc. and watch the displayed RGB values at the picker: very dark spots almost double, while bright spots increase only little.
2. The "linear adjustment" in PS works on the mapped data.
Try it out on several GREY spots: move the top right corner of the straight line in "curves" to the middle of the top edge (this corresponds to +1 EV). Make a selection on a dark spot and watch for the average under the histogram; turn the adjustment layer on and off. The RGB values got doubled. Now do this on a middle dark area: the same happens. Then pick an area close to but less than 128: you get close to 255. Try it with an area over 128, no matter how intense: you get 255.

The Zone System (Linear Tone Curve?)

Hi, I've been learning the zone system by Ansel Adams. I would like to take a photo and import it into photoshop so that each value in my scene matches the according grayscale measurements in photoshop (measured using Lab values).
I used my camera and took 11 exposures of a grey card: -5 ('Black'), -4, -3, -2, -1, 0 (Mid Grey), +1, +2, +3, +4, +5 ('White').
I then opened the files in Adobe Camera Raw (No adjustments)
I then opened them with Photoshop
I measured the Lightness values using Lab and plotted the points on a graph.
I see that somewhere along the line an S Curve has been applied to the input values! I would like an even distribution of the input tonal values.
How do I turn this S-curve off? Or, how do I achieve a linear curve when importing photos to photoshop?
Essentially:
I would like a linear response curve so that each tone (each 1 stop exposure from above) maps to the appropriate grayscale value in even increments (i.e., 10% steps).
Zone 0:     0% (Black)
Zone 1:     10%
Zone 2:     20%
Zone 3:     30%
Zone 4:     40%
Zone 5:     50%
Zone 6:     60%
Zone 7:     70%
Zone 8:     80%
Zone 9:     90%
Zone 10:   100% (White)
Can anyone shed any light on this issue? I'm really stumped with this one!

This looks like a typical response curve that you would also see with film. I'm not sure you would want a linear line, as your images would look flat. If you really want a linear curve, play around with the curves in ACR and adjust them so that they compensate for the curve that your camera sensor is creating.

How important are camera settings if you use ACR?

How important is it to properly adjust the settings on your camera when taking pictures if you can change white balance, exposure, etc. in ACR?
Just curious....

How important is it to properly adjust the settings on your camera when taking pictures if you can change white balance, exposure, etc. in ACR?
Just curious....
It is critical to get exposure right in the camera. If the dynamic range of the scene is less than that of the camera, you have some exposure latitude, but it is best to expose to the right so as to get a better signal to noise ratio. Some degree of overexposure can be corrected in ACR, but blown channels (the green usually blows first due to white balance) result in loss of data and the colors may not be accurate. The white balance set on the camera does not affect the raw data, but is merely stored as metadata. If there is no neutral reference in the scene (a WhiBal or similar card is better than a white T-shirt), the an accurate white balance may be hard to obtain. In this case, it is better to use a WB preset by taking a reading from a white balance card.
ACR ignores camera settings other than WB, so the contrast, saturation and tone curve set on the camera are of no significance.

ACR VS RAW Developer for image detail

I am an avid/loyal ACR fan who makes mural sized landscape prints from digital capture. I keep hearing on various forums how Raw Developer (Mac) is the best out there for extracting every ounce of discernable detail from a raw file to a print. I am to the point of considering purchasing the software to do the tests.
If it proves to be a real world benefit, I will likely have to use it.
What has been your experience with Raw Developer vs. ACR in terms of quality detail?
If the above is true, might ACR step up to bat and give us another optional algorithm for maximized detail (like a "maximize detail" button in ACR to choose a more detailed conversion)?
Feel free to comment on the issue however you want.
I want detail!

I was a big convert and advocate for Raw Developer. I paid my $125 to Brian and I don't regret it one bit. He's a cool and patient guy and answered my emails without fail.
However, the more I got into using the color editing tools on a number of differently exposed and composed images with varying color temps, the more I started not liking what it did to the color. The default settings were pretty good but whenever I adjusted color temp and the saturation and hue sliders including other adjustements I noticed a strange patina in the hues that showed up in my edits that bothered me.
For instance when adjusting RD's red/green tint slider the green looks more like a urine green where as ACR's hue is more pure. When I placed side by side previews of the same image between the two converters I noticed RD's deep shadows on a number of images were void of any color while ACR's retained it.
Some users like the look of neutralized shadows on their display, but from my experience it doesn't look too good on a print. I come from a painting background and charcoal neutral shadows is a big no-no when painting shadow detail on canvas. It ruins the 3D effect. This is the main reason why offset pressman will either include an extra cyan plate duplicate of the black channel or mix blue into the black ink on press. It adds pop to the image.
ACR's color engine is far superior in this respect.
Also I get odd zipper like sharpening artifacts along edge detail in some images with RD. It's still an amazing Raw converter in that it retains the simple interface as ACR with added color controls of Lab and RGB curves which ACR doesn't. But I found I had to work to much to get what I wanted compared to using ACR.
Your experience may be different.

Cropping in Lightroom and ACR+edit in Photoshop

Using the latest versions of Photoshop CC and Lightroom. After editing a raw file, including cropping, in either Lightroom or ACR and then
proceeding to Photoshop, the adjustments-exposure, white balance etc. are imported but not the crop! Very strange. Help would be appreciated in
solving this problem. Thanks in advance.

Thanks for the quick reply Graeme. That is correct. I have tested the issue with a representative from NIK/Google. The "selective tool" was causing the problem. I was dealing with other problems too, like the "exposure" slider in ACR was jumping back all the time. I have been following another discussion concerning this (http://forums.adobe.com/message/5806682#5806682). I have not tried it yet, but there they have had success tackling the problem by changing the Country/Region.
Regards,
Kamiel

Major differences between ACR and Aperture in red channel

Hi!
I did some printing a couple of days ago and the result was really not acceptable. At first we thought it was the printer and then the process of saving the files from tiff mac to tiff pc. After that we hade a look at the channels and the findings explained exactly why we got the result. After that I decided to compare ACR with Aperture and here are the differences in the Red channel. Camera is Canon EOS 350D, ISO 200. The image is 25% zoom. I don't know if it is possible to post images but a link is perhaps good enough.
http://www.d.kth.se/~vendelin/ap-acr.jpg
Do you have any ideas why Aperture gives me this result? If this is what I can expect from Aperture I'm afraid I'll have to use another raw converter for printing and that is a shame. The Image look fine in RGB but Red is destroyed and the printer in this case uses the red channel I'm told.
kind regards,
Edvard

Obviously that would be one way of doing it but
digging after every file in the aperture lib, opening
them in ACR, saving as tiff 16, importing to aperture
is a to painful process.
If you have to do it for every image it would be annoying, but if you don't often have blown out color channels it would not be too bad...
I actually use Aperture myself by importing TIFFs because my camera is not supported in Aperture directly.
As you pointed out the dark
area is in fact not dark grey but black. No
information there what so ever. Is this a common
problem with aperture? Has anyone else experienced
this or is this image an extreme example?
I'm not sure why that would be, that's a different issue. I have not seen anything like that as Aperture seems to recover as much detail as any other converter.
Are you sure there is no detail there, if you raise exposure some? ACR is set by default to automatically change adjustments, you may want to try auto-level or something like it.
<...>
Is this really a problem with Core Images or is it an
Aperture problem? Correct me if I'm wrong but
aperture uses the same RAW converter as iPhoto does,
in other words Core Images framework? I see why Apple
want Aperture, iPhoto and other to use their raw
converter that's built into the operating system but
when the performance is lacking perhaps the Aperture
team should consider to build one for them selves?
<..>
You are thinking about it backwards. What Apple is doing is to spend resources producing a pro level converter, which then every part of the system (including iPhoto) can use. If Aperture were going to build thier own RAW processor then why would you not want iPhoto to be able to use it as well?
And in fact that's pretty much what happened, before Aperture came out OS X RAW conversion was pretty mediocre. But after Aperture Apple spent a lot of resources improving RAW conversion and it's far better now - whcih also benefits iPhoto.
Is there any form of modified RAW converter for OS X
I could use to replace the one shipping default? I
would do anything in order to keep using aperture for
prints also.
Sorry, there's no way to swap out the OS decoder.

ACR errs in reading "as shot" WB from my D200

I am working with the latest release of ACR. Recently I have discovered that it does a very poor job of reading the white balance data in the exif from my Nikon D200. First I noted that when the in-camera WB was set to flash (5400K according to Nikon manual) the "as shot" WB temperature displayed in ACR was 6150K. Next I tried setting the in-camera WB to specific temperatures (from 4800K to 6300K). When the raw files were opened in ACR the "as shot" WB readings were all shown as lower temperatures, with a drop ranging from 11 to 14 mired. Compare this to the increase of 23 mired when WB was set to "flash" on camera.
Is it possible that I have some hidden setting somewhere that is interfering with ACR's reading of the exif WB? Or is this considered a normal deviation? I have searched the archive but find no information concerning this problem.
Thanks/Mike

G Sch
Thanks for your replies. It may well be that Nikon's color temperature values are off. However 5400K is a reasonable value for a flash exposure, and for ACR to "correct" this to 6150K does not seem reasonable.
If I set the camera WB to flash (5400K) and take an exposure of a white wall, when the raw image is opened in ACR the "as shot" temp shows 6150K and the image is obviously way too warm. Changing the WB in ACR to 5400K produces a neutral image. Using the WB eyedropper in ACR also shifts the temp to approx. 5400K.
I don't have access to Nikon NX. What would be the point of using the camera's WB preset capability if ACR is incapable of reading the metadata correctly.

Exposure Curves in ACR

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