Laura Shoe's Lightroom (and Occasionally Photoshop) Blog for Digital Photographers

Archive for August, 2011|Monthly archive page

Important Message to My Readers

In Uncategorized on August 13, 2011 at 8:25 pm

The Digital Daily Dose  (Laura Shoe’s Lightroom and Occasionally Photoshop blog) has moved to!

Have no fear, the Digital Daily Dose will continue.  I  simply decided to integrate my website and blog, to bring all resources together into one easier-to-use site.   I am still working on some of the details, so look for even more new features soon.

Please update Google Reader or other content readers/feeds that you use to include this site,   If you were an email subscriber on the old site (or not!), please subscribe again at in the sidebar to the right — scroll down to the Follow Me section.

I hope you enjoy the new site, and will visit often!    Feedback is always appreciated — on the new site, please leave a comment if you have any suggestions or thoughts.

8 versus 16 bit — What Does It Really Mean?

In Uncategorized on August 9, 2011 at 8:00 am

(If viewing from blog home page, click on the post title to view the post larger.)

You may be shooting in raw rather than jpeg because you know that raw files contain more information and because they are unprocessed, giving you more flexibility.  But how do they contain more information?  Among other things, raw files are captured at a higher bit depth — depending on the camera, 12, 14 or 16 bit, compared to 8 bit for jpegs.   Whether 12, 14 or 16, these higher bit-depth files potentially contain much more information than 8 bit files.

What’s the big deal?   For each pixel in your image, the tonal value or brightness of the scene you are photographing  is stored in the image file on your memory card, along with the color.   Computer files store information in zeros and ones.  Bit depth refers to how many digits  the tonal information for each pixel is stored in.   Imagine if your camera used a bit-depth of one:  you would have one digit to store how dark each piece of the scene was, the only possible values would be 0 and 1, and the only two tones that could be represented are black and white:

Image From File with Bit Depth of One

This image of course has very little detail, since it contains no shades of gray.

If the file had a bit depth of two, there would be two digits, and the four values of 00, 01, 10, and 11 would be possible, so the image could have black, dark gray, light gray, and white:

Image from File with Bit Depth of 2

Notice that we have gained some detail, but that the image is still very choppy.  In the histogram for this image, below, we see huge gaps between the tones, confirming the choppiness or posterization.  (The histogram is a graph of the tones in an image, going from pure black on the left side to pure white on the right side.)

Histogram for File with Bit Depth of 2

Let’s jump to a file with a bit depth of 5, which allows 2 to the 5th, or 32 possible values from 00000 to 11111:

Image from File with Bit Depth of 5

We gain alot of detail, but there is still obvious posterization in the sky (click on the image to see it larger).  The histogram supports this:

Histogram for Image with Bit Depth of 5

Now let’s jump to 8, which allows 2 to the 8th, or 256 values, and is what a jpeg supports:

Image with Bit Depth of 8

Histogram of Image with Bit Depth of 8

This image shows the full detail of the scene with no visible posterization, even when viewed at full size, and the histogram looks much better.  (If you see any posterization, it is not real, but rather just the result of my blog save process.)  So why not stop here, with 8 bits and 256 tones?

The problem is that as soon as you start enhancing your image, you start compressing and expanding the tonal range.  This creates choppiness in the histogram and potentially, visible posterization in your image.  To show this, I took this 8 bit image into Photoshop, and added contrast and darkened it:

Darkened and Added Contrast to 8 Bit Image

Notice how this pulled apart the histogram:

Result of Working 8 Bit Image

The more heavy-handed your adjustments, the more and wider gaps you will end up with in your histogram, and the greater possibility that you will see posterization in your image.  256 tones is often not enough for the fine detail in the image to hold together.

12 bit files have over 4,000 tones, and 14 bit files have over 16,000.  This is vastly better, and with almost any work you could do to an image, it would hold together.  Here is the histogram from the 12 bit version of the above image, with the darkening and increased contrast:

Histogram from 12 Bit Version with Darkening and Contrast Boost

To have this additional “editing headroom”, you have to capture a high bit-depth image, i.e. a raw file, and you have to enhance it as a high-bit depth file.  It does no good to convert a raw file into 8 bit as you move into Photoshop to work it.  While you are working in Lightroom or Camera Raw, your work on your raw file is in 16 bit (standardized to accomodate 12, 14 and 16).  When you move a file from Lightroom or ACR to Photoshop, you need to ensure that the Photoshop file stays in 16 bit.  In Lightroom, go to Edit or Lightroom>Preferences>External Editing, and set your PSD or TIFF preference to 16 bit.  In ACR, click on the workflow options at the bottom of the screen and do the same.

Higher bit depth files also potentially have a much larger number of colors:  an 8-bit  jpeg can represent around 16 million colors, whereas a high bit-depth file can represent over 28 billion.  Perhaps we could make do with 16 million, but if your photography is important to you, why not start out and work with the best quality image possible?

The downside to higher bit-depth is larger image files — all else equal, a 16 bit image file is twice as big as an 8 bit image file.  But large memory cards and hard drives are so much cheaper these days than they used to be.

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A Request to My Readers

In Uncategorized on August 5, 2011 at 11:46 am

Have you seen me teach in-person,  enjoyed my Lightroom DVD, watched a video on this blog (like this one on developing an image, or this one on using the adjustment brush), or just like my written tutorials?

Please consider nominating me to teach Lightroom or Photoshop for, a great online photography education site.  It only takes a moment — you can do so HERE.   They ask for my website — it is (and for those of you who know the Digital Daily Dose, but not my name — it’s Laura Shoe!)

Thank you!!

Stay Organized — Name Your Virtual Copies

In Uncategorized on August 4, 2011 at 9:09 am

If you want different versions of an image, such as with different crops or both a black and white and color one, you can create virtual copies.   These aren’t duplicates of your file — you will still just have one file on your hard drive, but multiple sets of Develop instructions for that file.  To create a virtual copy, right-click on your image and select Create Virtual Copy.  In the filmstrip you will see that the virtual copy has a turned-up page corner (if your filmstrip is big enough), and that Lightroom automatically stacks (links) the two together.

You probably already knew all that, but did you know that you can name them?  They are actually automatically named Copy 1, Copy 2, etc…  This isn’t the File Name, but rather the Copy Name, which is another metadata field.  As you hover over the virtual copy in the filmstrip, it shows the Copy Name after the file name (see above).   I always use this field to document what the virtual copy is for — otherwise I end up with lots of virtual copies that I can’t for the life of me remember why I created.

Changing the name requires going to the Metadata panel in the Library module — scroll all the way down on the right side.   Simply click  and type in the Copy Name field and then hit Enter/Return.

I also find it useful to display the Copy Name above my thumbnails in Grid view in the Library Module:

You can do this by going to View>View Options, and setting the following circled in Red:

When you export virtual copies, you can also rename the exported copies to include the Copy Name.  In the Filename Template Editor, Copy Name is under the dropdown called Original Filename.

I’m not going to go into how to use the template editor here, but I do have a video on using it  HERE.   It’s an old one, so (a) it uses Lightroom 2, but there have been no changes, and (b) you’ll need to turn the volume way up.  (I have of course since learned how to do this in the video production!)

So you can see how handy and easy it is to name your virtual copies — so I say, just do it!


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Blurring Backgrounds in Lightroom

In Uncategorized on August 1, 2011 at 9:19 am

I posted this tip a little over a year ago when Lightroom 3 came out, but I thought I’d post it again, since surprisingly it is one of my most-read posts.

Looking to blur out a background to reduce distractions?  In Lightroom 3, use the adjustment brush with Sharpness at -100.   If this is not enough blur, do it again:  click on New to start a new adjustment, and paint a second time.    If you blur out an object that you want to keep sharp, use the adjustment brush and paint back over the object with +100 Sharpness to restore its sharpness!

Also consider using the graduated filter with -100 Sharpness to simulate a shallower depth of field where the sharpness drops off gradually.

If you don’t know how to use the adjustment brush, here is a video on it.  It is a sample video from my new Lightroom DVD.