Tag: Noise reduction

Switching between old process and new process in Lightroom 3

Lightroom 3 is built around a new, improved demosaicing engine (the raw converter code that makes a full-resolution, full-colour image out of your raw file). It also includes the older conversion engine used in Lightroom 2 and earlier so to see the full power of Lightroom 3, you need to make sure you’re using what Adobe calls the 2010 process (that’s the new raw conversion engine) on each of your raw files. The old engine is referred to as the 2003 process. (In Lightroom 3 public beta 1, they were called process version 1 and process version 2—the new names are a definite improvement.) This is a per-image setting so you can choose which images use which process and can mix old and new in one catalogue.

How do you tell which process you’re using?

As of Lightroom 3 public beta 2, the main sign that you’re using the old (2003) process is the unmissable presence of an exclamation mark in the lower right of your image when you’re in the Develop module. The symbol appears next to any image that’s using the old engine and looks like this:

To switch to the 2010 process, just click that warning symbol. You’ll get the chance to review the before-and-after changes and to apply the changes to the whole filmstrip. Comparing the the changes side by side at 100% can be a useful way to understand the differences between old engine and new.


Above; the box you see when you click the exclamation mark in the Develop module

A warning about noise reduction and sharpening

In Lightroom 3 public beta 2, released today, local sharpening controls (brushes, gradients) and luminance noise reduction are both much more powerful than they were in Lightroom 2. You might find some settings for sharpening, negative sharpening and luminance noise reduction that you’d used previously to be way too high for the new versions so carefully review as you update your work.

To switch back to the 2003 process

To remind yourself of how a picture looked using the old demosaicing engine (aka process version 1 or the 2003 process), you can always switch back. In Lightroom’s Settings menu, go to Process, where you’ll see a choice between the 2003 version and the 2010 version. (The old process is labelled 2003 because Adobe Camera Raw—or ACR—dates back to that year. Even though Lightroom was only released in 2006 as a public beta, it shares code with ACR, which means that at some point, there will be a version of the ACR plugin that has offers this new raw conversion engine, too.)


Above: switching between processes using the Settings menu

Alternatively, you can now choose your process version from a new menu item in the Camera Calibration section of the Develop module (lower right).


Above: the new Process menu inside the Develop module’s Camera Calibration section

Use virtual copies and the compare function

When you begin to use Lightroom 3, it can be useful to make a virtual copy of a picture and use the old engine (2003 process) and the new side by side on the same image to get a feel for the difference between the two raw converters. For the full effect, choose a high-ISO image, with local sharpening applied. The second public beta now includes an option to view images side by side when you convert from the old process to the new but it can be useful to do it manually, particularly for images in which you’ve used many brushes. Compare results at 100% using the compare function (hit C in the grid, with both versions of the picture selected) and you should see a significant—and sometimes dramatic—difference in quality.

Why do some or all files use the old process version in Lightroom 3?

If Lightroom 3 can tell that you’ve done some work on a raw file in Lightroom 2 or a pre-v6 release of Adobe Camera Raw, it will keep using the 2003 process for that image so that the picture continues to look just as it did in Lightroom 2. That’ll happen if it sees an XMP sidecar file next to the raw file and can tell that the XMP file was created by Lightroom 2 or ACR 5.x or earlier.

What are the main differences between the 2003 process and the 2010 process?

The new 2010 process uses the new demosaicing engine in Lightroom 3, offering finer detail and better rendering of high-ISO work, among other things. Dramatically improved noise reduction, too, and much more powerful local sharpening controls. (Brushes, gradients.)

For an early and subtle example of the difference in quality between version one and version two with default settings, even at low ISO, see an earlier post on protecting fine colour detail in Lightroom 2. Towards the end, it contains some Lightroom 3 screen shots of the example image—there’s a clear difference in the way that colour noise reduction works.

Now that Lightroom 3 beta 2 is available and contains working luminance noise reduction, we’ll post more example files soon. Initial testing suggests very impressive NR results but it will take more time to be absolutely sure.

Edge Detail in Lightroom 3 beta: what does it do?

Adobe Lightroom 3 beta offers many refinements and some new features over Lightroom 2. One of the most intriguing is a control labelled Edge Detail. The slider is intended to deal with the smearing of colour that you sometimes see in very high-ISO shots, when noise reduction has reduced the sharpness of edges and the colour might leak from one part of the image into another.

The edge detail slider at work

Here’s a very mundane picture. It wasn’t taken at very high ISO (just 500) but was pushed to about ISO 2,000 equivalent during post-processing and was taken on an older camera that has a very noisy sensor by today’s standards. (As a point of reference, any of you shooting the new Nikon D3S would probably need to go to ISO 25,000 or 50,000 to get anything quite this noisy.)

Edge_Detail_Shoot_Raw_Full

Now take a look at a detail from the image, first with the new Edge Detail slider set to zero and then, in the second crop, with the slider set to 100. Look at the way the edges of the orange indicator lamp are defined against the car’s bodywork.

Edge_Detail_0_Shoot_Raw_Crop

Edge_Detail_100_Shoot_Raw_Crop

You can see the effect of Edge Detail quite clearly—it appears to be adding sharpness and clarity to the colour edges, emphasising colour boundaries in a way that regular sharpening doesn’t and getting rid of much of the orange mush that you can see in the top picture. (In Lightroom, regular sharpening acts only on the luminance data—i.e., the brightness—and not on the colour. That’s intended to prevent colour shifts.)

Digital photography allows us to work in very low light but the level of colour noise reduction going on often smudges the colour; Edge Detail has been designed to counter that where it matters and can be quite effective—it just needs a better name.

Indoor, ambient-light photographer?

Although this slider is a feature of the beta version of Lightroom and could change (or even disappear) before the final release, it might be worth an early look if you’re an event photographer shooting with only ambient light and sometimes end up working in some challenging, low-light conditions. If the Edge Detail feature makes it through to final release, you’ll also see it in the corresponding version of Adobe Camera Raw (ACR) for Photoshop, which is rumoured to be ACR 6.

Workflow and notes

  1. All the processing for the image above was carried out only in Lightroom 3 beta, and designed to show the effect of the Edge Detail slider as clearly as possible.
  2. The only difference between the two crops is that the Edge Detail slider was moved from zero to 100—no other control was touched.
  3. Lightroom 3 beta is a free download for Windows and the Mac, even for users who have no version of Lightroom currently installed. It’s beta software so it has bugs and some performance issues that will be ironed out before a final release. It will expire in April 2010.
  4. All the images used above show lots of noise because Lightroom 3’s luminance noise reduction is disabled in the current public beta.

Training

In case you were wondering, our training is not this geeky—it’s about workflow rather than esoteric details! We put this stuff in the blog so we don’t have to spend as much time covering it in regular courses. If you find this kind of thing useful or interesting and know others who might, we’d love it if you could pass on details of our site.

Protect fine colour detail in Lightroom 2

The colour noise reduction slider in Lightroom is set to 25 by default. In Lightroom 1 and 2, that value is often too high.

Screen shot of Lightroom noise-reduction sliders

Colour noise reduction is subtle

There are some controls in Lightroom that have clear and immediately visible effects but colour noise reduction isn’t one of them. Slide the saturation control a little and you’ll get a pretty good idea of what it’s doing to your image but with colour noise reduction, any change can often be very slight or invisible, particularly at low ISO and certainly as you slide it between its default and zero. So it’s very tempting—particularly if you only shoot at low ISO—to quietly ignore it…

Resist temptation

Left to its own devices, colour noise reduction can remove significant colour detail from some of your images, even when there’s no little or no colour noise present—and you may never know what you’re missing. Take a look at the simple test shot below; it was taken with the camera set to base ISO and f/8, using a sturdy tripod and the fading light of a late November afternoon in London. (If you’re reading this in your e-mail client and see no images, click on the heading of the message to continue reading the piece in your browser.)

Origami_colour_noise_reduction
Above: the complete image, resized for the web

Below is a 100% crop from the photograph, presented in two versions—one with colour noise reduction left at default (25) and the other with it set to zero. The Lightroom settings are otherwise identical in every way. The difference is quite striking: with the colour noise reduction gone, the subtle colour pattern printed on the paper is suddenly clear and becomes an important part of the picture’s texture. Take a close look.

Origami_crop_noise_reduction_25
Origami_crop_noise_reduction_00
Top photo: colour noise reduction slider set to 25.
Lower photo: slider set to zero. No other changes.

The only thing it took to reveal that subtle printed detail was to move the colour noise reduction slider away from its default. It’s the same raw file, same sharpening, same JEPG compression on output—same everything. That should give you an idea of how colour NR might affect the fine detail in your work, whether you shoot landscape (subtle tonal variations and detail in in grass and foliage), portraits, product shots or fashion (think of fabric detail). If you offer large, fine-art prints in colour or display large images online, it may pay dividends to pay attention to that harmless-looking slider.

How about Lightroom 3?

As of November 2009, the current beta version of Lightroom 3 has a completely reworked noise-reduction algorithm; like its predecessor, it comes set to 25 by default but that and the name of the slider seem to be about the only things carried over. The new version in Lightroom 3 removes far less valid colour detail from the photograph. Here’s a crop from the same raw file, this time processed in Lightroom 3, with all settings unchanged.

Colour noise reduction at 25 (default) in Lightroom 3
Above: in Lightroom 3 with colour NR set to 25

This time, with the slider left at its default, you can see the printed pattern very clearly. There’s more good news, too: as well as being far less intrusive, the new noise reduction routines in the beta version of Lightroom 3 are also more effective. (We’ll have detailed examples coming up in articles on noise reduction, in which we’ll also look at the surprising differences between a few of the dedicated noise-reduction packages available.)

Our recommendation for Lightroom 2

When you begin to work in Lightroom 2.0, (Amazon UK link), start by leaving the colour NR slider set to zero, increasing it only when you see colour noise. You can best identify colour noise when viewing your work at around 100% to 200% magnification. (That sounds excessive but try it—it makes life easier, particularly when you’re getting started.) In a short time, you’ll be able to choose values for noise reduction that depend on the camera’s ISO setting for the shot, your approach to setting your camera’s exposure and the importance of fine colour detail in your work. Remember to take the images all the way to final output (meaning print, if that’s how the images will end up) before you settle on your starting values.

Presets

When you’ve found your way around these settings, build one-click presets for your commonly used noise-reduction settings and your workflow will speed up considerably. Good use of presets is a big help in achieving a fast, easy raw workflow while maintaining image quality.

Noise reduction, edge masking and sharpening

Even if the odd default value might be a little off, the noise reduction functions in Lightroom (including version 2) are already a lot better than most Lightroom users realise when should be used in conjunction with Lightroom’s edge masking and sharpening controls. When you make the most of these controls, they can produce excellent results. More on that coming up in future articles.

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One-on-one training

And another reminder. As always, we’re available for one-on-one training at your studio, home or office and we still have free slots in December 2009 and January 2010. In a day, you can easily get enough information to get you up and running confidently using a raw workflow; alternatively, you can choose to concentrate on particular aspects that are proving a little tricky. Our minimum booking is a half-day in the London area and a full day elsewhere. We’re also putting together phone support packages. Call 0333 577 5703 (regular London landline number) or drop us a line for details.