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.

Similar Messages

Apple please rework the auto exposure adjustment

90% of the time, the result is worse than before. It seems, Aperture's auto exposure adjustment is based on an average of the whole picture. So in its effort to get a well distributed histogram over the whole range, it happily blows the brighter parts of the picture.
I usually try to recover most of the highlights except small reflections etc. and then lighten up shadows and mid-tones with the appropriate tools to get a well exposed picture.
So I would prefer, that the auto exposure adjustment would be more sensitive towards blown highlights especially larger contiguous areas of highlights.
If you can't find an algorithm that works reliable, probably give me two separate auto exposure adjustment buttons. One adjusts to overall good exposure, like it is currently, the other tries to prevent blown highlights.
An even more advanced auto exposure adjustment would be, to combine the current exposure adjustment with some shadow and mid-tones adjustment, in case the exposure adjustment with preserving highlights led to an underexposed image.
I don't expect this to give perfect results, but it would be a real timesaver to use it as a starting point for manual fine tuning.
Not to bash Aperture but to encourage you to improve it: ACR's auto exposure mechanism is doing a much better job than Aperture's current one.
Peter
Quad G5 Mac OS X (10.4.8) GT 7800

Well, obviously all your photos are already exposed perfectly!
(Seriously: when you say "nothing happens", do you mean absolutely nothing? Does the "Exposure" panel's check-box become checked after you hit the Auto button? If so, then it made SOME adjustment (though perhaps not enough for you to notice, see initial comment!) If not, then yeah, something is not working right for you.

Exposure adjustment layer for 32 bit HDR images

I know I can adjust exposure in Camera Raw. I can use the adjustment brush to make local exposure adjustments in ACR too. Is it possible to make exposure adjustments to 32 bit images in Photoshop? My attempts at using the exposure adjustment layer weren't successful. Although I'm told "exposure" was designed for 32bit, the adjustment layer doesn't seem to be to access and manipulate any of the exposure data thats I know is in the file, but is not visible. It would be should be so useful, but from what I gather the exposure adjustment is totally useless for 32 bit images. Are I doing something wrong?

Thanks for the reply. I'm struggling to explain so i'll try and illustrate instead. Basically the Exposure adjustment layer does not work on the 32 bit file in the same way that ACR does. ACR changes exposure in the predictable way it should (like a raw file). The Exposure adjustment layer in photoshop doesn't work the same way. Or at all?

Add second Exposure Adjustment

Hey there,
I was wondering if you could somehow add a second 'Exposure' Adjustment as you can add multiple times for example curves or so.
Thanks.

Hi Nikolas.
Nope . Exposure Brick adjustments, per Image, are global and singular. Once you set them (I recommend setting them so that they give you not the _the exact_ final results you want, but rather the latitude to make other adjustments that give you the final result you want), you use other adjustments to further refine the "exposure".
See this page in the User Manual. (Added: Actually, that page isn't as helpful as I had expected. Use "Exposure" to give you the broadest range of usable data. Then use either Curves or Levels to re-map that data where you want it for the whole Image. Then use Quick Brushes and/or additional brushed-on Curves or Levels adjustments to re-map local subsets of your global data. At least, that what I do .)
HTH,
--Kirby.
Message was edited by: Kirby Krieger

Is it possible to define a global keyboard shortcut for Exposure Adjustment?

I often find myself having to get out of full-screen mode or having to pull up the Develop or Library module from the hidden right panel just to adjust exposure and nothing else (it is my most common adjustment).
Is there some way to globally define a key so I can adjust exposure without having to exit full-screen?

Globally? No.
However, if you click on the word exposure, you can indeed adjust exposure with the + or - keys.
I believe you'd have to do this on each photo, and if you click on another word in the Basic panel then that slider is now controlled by + or - (for example, if you click on contrast, then the + or - keys adjust contrast).

Problem with exposure adjustment in Camera Raw

I'm a long time Photoshop user, currently on CS6. Recently I've been having problems with adjusting exposure in Camera Raw. For some reason, it now only works in full stops. Nothing in between works. Same problem with the adjustment brush.
I updated today to the latest version but the problem remains. All other adjustments are working as they should.
Can anyone explain what happened and how I can get back full funcionality?

I have found an acceptable solution to the issue (already posted in this thread: http://forums.adobe.com/message/5920583#5920583 ) after invaluable tips from forum members.
The problems are indeed caused by the Nik plug-ins, and specifically by the Selective Tool plug-in. But you don't need to uninstall anything.
Solution: In your applications folder, choose Photoshop/Plug-ins/Google and you will find the various Nik plug-in folders. Add a tilde sign to the Selective Tool folder (like this: ~Selective Tool). Close Photoshop and open it again. Camera Raw should now be working without issues. The Nik plug-ins will lose some funcionality, but nothing really serious. You will have to manually duplicate a layer before using a Nik filter and the filters won't work with multi-layers. If you desperately need full funcionality, close PS, remove the tilde sign and open PS again.

Aperture 2.1 Sluggish Exposure Adjustment Sliders

Description of Problem:
1. When the Straighten Brick is applied to an image being adjusted, the Exposure Brick sliders become erratic and do not track mouse movement or the Wacom Tablet Stylus tip.
2. This condition substantially worsens when the Highlights and Shadows Brick sliders are also applied to the image simultaneously.
3. A similar condition appears with the combination of Crop and Highlights and Shadows.
4. This condition is so severe that I took my Mac Pro 2 x 2.66 GHz Dual-Core Intel Xeon with 4 Gig's of Apple Ram and NVIDIA GeForce 7300 GT 256 Vram Computer to the Apple Store Genius Bar for diagnosis and possible repair.
5. After my having demonstrated the problem, the Genius Team took my set of internal hard drives out of my computer and installed them in a brand new Mac Pro in the Apple Store, where the problem persisted, thus eliminating my hardware as part of the the problem.
6. It was then suggested to me by the Genius Team that I create a new Aperture Library, trash my Aperture Preferences and re-import my images into the new Library. The sluggish and erratic Exposure sliders problem persisted!
7. I then, on my own, created a third Aperture Library and imported only a few images. As long as the Straighten Brick is not part of the adjustment pallet, the Exposure Brick sliders behave normally, tracking the mouse or Wacom Tablet Stylus Pen tip.
However, when the Crop and or Straighten Bricks are added or combined with the Highlights and Shadows Brick sliders, the Exposure and White Balance sliders become erratic, sluggish and nearly useless.
Of note, the Enhance sliders, however, are unaffected by the above combination of Adjustment Bricks.
8. I then tested this scenario on both the 2 x 2.8GHz Quad-Core Intel Xeon and 2 x 3.2GHz Quad-Core Intel Xeon Mac Pro models in the Apple Store, with extremely similar results. The later, 3.2 GHz Mac Pro with the NVIDIA GeForce 8800 GT 512MB Video card installed and having 4 Gigs of Ram.
9. I tested the scenario with my images as well as with the the sample images installed within the Aperture Application Library, both with identical results.
10. Clearly, this phenomena is a defect in the Aperture Software, as it can easily be demonstrated independently of specific Apple hardware, and as it is very common to apply the Straighten, Crop, Highlights and Shadows adjustments to an image, renders the Aperture Application useless, as an effective workflow solution. A Professional Photographer cannot guess at the Exposure settings and or wait and hope for the adjustment slider to track mouse movement while it jumps around erratically in the process.

What you're doing simply requires more calculations than your processor can perform in an acceptable amount of time. The tradeoff of the non-destructive image editor is that every transformation you apply has to be recalculated and effectively re-applied every single time you make any change to any one of them on the stack. Given the average size of a modern camera raw file, this gets very expensive very quickly.
There are certainly ways of caching intermediate data in the interest of drawing speed, but the white balance and exposure sliders fundamentally change every aspect of the image data's interpretation and are some of the most expensive operations you can possibly perform. Not only does it have to loop through every single pixel in the image to calculate the various gamma encodings you ask it to with every little nudge of the slider, but it also has to rotate them all by however much you've asked the straighten tool to. Top that off with the fact that Aperture has never been widely regarded as a "speed demon" and you've got laggy sliders.
Try Lightroom. You'll probably find it lags at times, too.
Now try sharpening a 1MB file in Photoshop 2 running on a Quadra. Not so long ago we had to wait hours for every single trivial adjustment to our low res and completely unprintable images to complete only to discover that it wasn't what we wanted at all. This wasn't a defect, it was the result of pushing the available technology beyond its limits. I have no doubt that Aperture could and should be optimized significantly, but the fact of the matter is that artists will always find ways to saturate the bandwidth of any computer on the market, however powerful.

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.

Does the Z1 have manual exposure adjustment when recording videos?

Looked all over the internet but can't find an answer to this question. When recording videos with the Z1, is it possible to manually increase the exposure by way of a slider (usually a range of -2 to +2)? I know there's an option to choose spot/centre weighted etc, but can this variable by set in advance with a slider? I film a lot of indoor videos that often end up completely underexposed when left in auto mode, therefore manual override is a must for me.
If not, does anyone know of any third party camera apps that add this functionality?
Solved!
Go to Solution.

On mine, running Android 4.4.2, before recording I can do it using the row of icons on the left. Make sure 'SCN' in the top left corner ('scene', in other words) is set to 'off'. This is like selecting 'manual' rather than one of the automatic, scene dependant, modes and it opens up the use of the next settings icon below it, the one that looks like 3 sliders, which would otherwise be 'greyed out'. So now that it's white you can tap it, go in, and manually select your 'white balance' setting (I use 'auto') and also the slider that you mentioned that goes from +2 to - 2. The slider in this case is labelled as 'EV'. Did this help?

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.

HowTo? Script to adjust new PV-2012 sliders in ACR?

I've used ExtendScript with CS5 to browse and modify the "CalibrateAcr" scripts developed by Thomas Fors, and modified by Rags Gardner.
http://www.rags-int-inc.com/PhotoTechStuff/ColorCalibration/
Some of what they were doing was "over my head" ... I didn't fully comprehend what they were doing. The scripts were able to work with an image opened in Photoshop, and somehow adjust the ACR sliders for that image.
Those scripts assumed ProcessVersion 2010 or earlier, and had routines to modify Basic and advanced settings, such as Exposure, Contrast, Shadows, Blacks, etc. The point of the scripts was an alternate way to calibrate a camera sensor. The scripts are not maintained and considered obsolete, with better approaches to camera calibration now.
I'd like to figure out how to update those scripts to work with PV-2012, particularly changing "new" sliders on the Basic tab like "Shadows", "Highlights", and "Whites". My uninformed speculation is that routines to modify sliders for "Exposure", "Contrast", and/or "Blacks" may still work.

FrankMazz wrote:
Often I like to get solutions. But, often I'm just happy to know I'm not alone - misery loves company. Thanks Rob.
Thanks Frank. And I concur with Robert Shomler: auto-toned settings may not be usable "out of the box", but it can sometimes help to see what auto-toner would do with the various settings, especially whites, but also contrast and highlight/shadows (and blacks).
Sometimes I get stuck in a rut, and hit auto-tone, and go oh-yeah, I'm banging my head against a wall because I need more whites and less exposure, etc... (at which point I usually undo the auto-tone and continue manual toning, but more enlightened...),
Cheers,
Rob

While editing photos in Aperture, I'm trying to make an "auto" adjustment to the exposure but the button is grayed out and consequently doesn't perform any function, please help! Thank you, Mike

While editing photos in Aperture, I trying to make an "auto" adjustment to the exposure,
but the "auto" button is grayed out and will not allow any auto function to take place.
Please help!
Thank you,
Mike

Mike, are you working with raw images?
For some raw images auto exposure is not available, have a look at this manual page:
http://documentation.apple.com/en/aperture/usermanual/index.html#chapter=18%26se ction=9%26tasks=true
Note: Automatic exposure adjustment is available for Aperture-supported RAW images only. If you want to adjust the exposure of another file type, such as JPEG or TIFF, see Working with the Exposure Controls. For a list of supported RAW file types, go to the Apple website at http://www.apple.com/aperture/specs.

Exposure vs. Levels vs. Brightness/Contrast Adjustment Layers?

I have some photos that are a bit underexposed and I'm trying to brighten them up a bit and I made a Levels adjustment layer and also experimented with the Exposure adjustment layer. Are these essentially doing the same thing OR are there reasons to have a Levels adjustment layer along with an exposure one and a Brightness/Contrast one?
Thanks in advance.

The Exposure adjustment in Photoshop is primarily meant to correct tonal values of High Dynamic Range images, which are 32 bits. This command makes tonal adjustments using a linear color space or gamma instead of your image’s color space. You can use it on 8 bit or 16 bit images too, but the adjustments may seem rather drastic.
When rescuing poorly exposed 8 bit or 16 bit images, I prefer Levels or Curves because you have greater control. Brightness/Contrast, isn't something I use much.
Nancy O.

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.

Aperture hangs when adjusting the exposure....

After upgrading to Aperture 3, I've discovered that it often hangs when I try to adjust the exposure...have to force quit....happened three times today. Is this a known issue?

Yes. Read other threads on this. I work around by first clicking on an exposure adjustment without moving a slider. Just clicking sets Aperture to 'process.' Once you see 'processing' has stopped, you will likely be good to go. Also, if an image freezes Aperture, after relaunching the application, go back to that image and force a regeneration of the thumbnail (or preview). This too will help. And report to Apple. The more they hear, the more likely to repair the issue.

Exposure Adjustment in ACR

Similar Messages

Maybe you are looking for