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Provides: Raw image processing application
Developer: Adobe
Requirements: Mac OS X v10.5.7 or greater, Intel processor (1GB ram), 2GB of hard disk space
Premium Retail Price: Provided for free with any application that provides Adobe Bridge.
Once you start "shooting raw," you'll never go back. And once you start working with ACR 6.1, you won't want to go back to earlier versions. Yes, it's that good. From Lens Profile Corrections to the new Noise elimination tools, to the enhanced Post Crop Vignetting and new Grain feature, this is a powerful update.
Perhaps a quick background because the whole concept of a raw image can be a bit (or a lot) confusing if you are not familiar with what a raw image is. First off, every digital camera collects data in a raw format, but typically only dSLR or upper-end point and shoot cameras can save this raw information. What you get from any camera as a JPEG started out as a raw image and is demosaiced into a JPEG by the camera and that is then stored on the camera's memory card. What you want to do if possible, get that raw image before anyone or anything has mucked with it.
So what's the difference and why should anyone care?
The simple and quick explanation is that a raw image contains a LOT more information than a JPEG can because the raw image is a minimum of 12 bits per channel (as opposed to the 8 bits per channel JPEG) thus there is more data to refine and define the image. Plus, any changes you make in a raw image is only an "interpretation" of that image because you cannot change the pixels of a raw image. Thus, for example, if you inadvertently left your camera's white balance on Tungsten, with a JPEG image there's limited options available. However, for a raw image, this situation is no problem. If you've done this, all you do is to change the interpretation of which white balance you want on that image. If you shot one or fifty such images, correction is a few clicks away.
Probably the best thing I can do is to link you to a short monograph that explains what a raw image is, what's demosaicing, what the limitations are of a JPEG and all this should explain why you should care. The monograph was written by the late Bruce Fraser and can be downloaded here. At the very end of Bruce's article is an very prescient comment by Bruce where he mentions that since your raw image is never altered or changed in ACR (or any raw converter for that matter), if there are improvements in the raw converter, those benefits are always available to you. Now in ACR 6.1, that statement has come true: Adobe has done a significant update to its raw engine and you can take full advantage of the new capabilities.
[By the way, even if your camera cannot save raw images, that doesn't stop you from using ACR. As with earlier versions, you can open JPEGs and TIF images in ACR and do all of the alterations and enhancements that can be done to a raw image although you do not have as much control (there's less information in a JPEG than a raw image so there's less to work with) and since white balance is already locked in, you do not have the same options for correcting and enhancing white balance. But, despite all that, everything I'm about to discuss can be done to a raw, JPEG, or TIF image. Keep in mind that if you do adjust a JPEG or TIF image with ACR, any alterations on that image are stored with that image and the pixels themselves are not changed. Thus, to see the changes, one needs to open that image with ACR UNLESS you re-save that image into a new JPEG or TIF image.]
If you have any images that you've processed in the past, when you open those images now, you will see an exclamation point in the bottom right corner below the image as shown below. In addition, if you move to the "Camera Calibration" tab of ACR, you can see that there's a new Process popup menu that gives you the option of which Process (2003 or 2010) you wish to work with that image with. You can either select the popup or click on the exclamation point, it doesn't make a difference which way you make the change.
After the conversion, you may or may not notice a change with your image. So why do this? Simple, you now have access to the new tools and features in ACR 6.1 which include one of the best noise reduction tools available in the industry. For years, Adobe noise reduction was OK at best. Now in the updated Detail tab, shown below, there is not only luminance noise reduction (that works) but color noise reduction (that works without desaturating the image).
As seen in the image below, on the left is an original image. On the right is the same image that I've processed. The important thing to note is that often noise reduction often leaves the image looking plastic and/or neutered. Here, the image still maintains a texture and depth. (These images are at 100% viewing.)
Now that you have removed noise, ACR provides an improved feature to return some grain back into your image. Sound confused? What the issue is is that (digital) camera noise is considered not desirable while film grain is. Perhaps sometime in the distant future, digital noise will be just as desired (in the proper circumstances) as film grain is now, we'll see. Meanwhile, digital noise is caused by the electronic device trying to amplify what isn't there, similar to the hissing/humming noise you get from turning the volume up on your stereo system when there's no music playing. In this case, the electronic bursts show up in a digital image as speckels of white or color. Film grain is caused by the larger crystals used in the photographic process in faster film. The larger the crystal, the less light is required to activate the film. Thus, both digital noise and film grain are both created by the same need: make the film or the sensor more sensitive to light so the image can be captured at a faster shutter speed.
As shown below, the top image is very clear and crisp. The problem is that by not having any texture, the image almost seems flat and without character. In the bottom image, by applying some grain into the image, I've brought out some edginess to the image that otherwise was too clean. Ironic isn't it?
In the past there has been manual lens correction capabilities, but now it can be automatic if you check the "Enable Lens Profile Corrections" as shown below on the left. If Adobe has processed your camera and lenses, your image's EXIF data will tell ACR what camera body and lens you have and make a variety of Distortion, Chromatic Aberration corrections, and Lens Vignetting. If you want/need further enhancement, you can flip over to the Manual tab and futz away as you so chose.
If your camera is not listed, and you are ambitious, you can download the Lens Profile Creator yourself from Adobe Labs here. And even if you are not so motivated, if you consider the incredible number of Photoshop Users, you have to figure/hope that someone might be so motivated because once their work is uploaded, you will be able to update your profile collection. [Note: while these profiles are supposed to be sensor agnostic (that is, it shouldn't make a difference if you have a Canon 30D or a 50D), you will get better results from a raw image than a JPEG. Once you (or anyone) has created new lens profiles, this data can be uploaded to Adobe and at that point it can be added to the full list so that other's with your camera and lenses can take advantage of the corrections.
Post Crop Vignetting has had a problem in the past where it tended to alter the colors within the vignette regions. Now there are three options and you can see the differences in the cropped image below (you are looking at the top right quarter of the image). The top image has no Vignetting at all. 2nd image down is Highlight Priority which has the color shifts in the darkened regions. 3rd image down displays the Color Priority which maintains color but can lose details in highlight regions. Lastly, the 4th image down shows the Paint Overlay that simply adds a black or white overlay. These new options provide an excellent range of effects on Vignetting.
In the long run, you might be wondering why one would want to add grain, remove noise, make image corrections, and many other image enhancements within ACR rather than Photoshop? There are several reasons for this, but most of all it all goes back to the issue that any changes made to a raw image are only "interpretations" of that image and are not changes to the pixels. In addition, if you have 2 or 200 images that you want to give the same changes to as you did the first, it's a simple matter of copy and paste (or synchronize, or other techniques of making changes of one image the same as changes in other images). Does all this make Photoshop less necessary? Not at all because ACR cannot do layers or text or many many other of the wonderful things that Photoshop can do.
I should also point out that version 6.0, the one that was shipped with CS5, had performance issues when opening many images into ACR. This updated release, 6.1, restores the performance to essentially version 5 levels.
In short, ACR has come from a wonderful raw image processor to a wonderful advanced image enhancer. While there are no "layer" features within ACR, by utilizing Smart Object layers from within Photoshop allows you to manipulate multiple layers from the raw image within Photoshop. With applications like these, there are always options. Thus, ACR and Photoshop provide an image-working duo that creates a wealth of photo-manipulation, enhancement, and control. Even if you are using ACR on JPEG images, you will find increased functionality at the initial stages of image correction/enhancement that will carry through to the end of the process.
[Because this is not a product that can be purchased, there is no rating.] See:___________ Gary Coyne has been a scientific glassblower for over 30 years. He's been using Macs since 1985 (his first was a fat Mac) and has been writing reviews of Mac software and hardware since 1995.
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