You may have been told that a “good” histogram looks like this – all the way from black blacks (left) to white whites (right):

So this one is bad: no blacks, no whites:

As they say: it ain’t necessarily so. Not at all, in fact. The second histogram belongs to this foggy image:

While if we changed the histogram to what you thought was a “good” one, we get this:

Which is all very well if you intended that – and you might well, but it is not how that morning looked. It looked like the first image.

So here’s the skinny:

The histogram should go all the way to the left (pure black) if there are (or if you want there to be) blacks in the scene, and it should go all the way to the right (pure white) if there is (or if you want there to be) pure white in the scene.

When you import images in (or handle images in) Lightroom4, you can choose the “Process version”: 2010 or 2012 (or even older). The new default is 2012, which gives you all sorts of new tools and a new interface.

In the Develop module, the first choice under “Camera Calibration” looks like this (2012 being the default):

The old edit basic pane with LR 3 was like this:

The new one is very different and looks like this:

The problem is that the new process version (“PV”) has “auto highlight recovery”.

So when I shoot an image with a blown out background, as I do in many shots like this, I used to see:

The red areas are Lightroom’s way of indicating a blown-out area where all detail has been lost.

Just as I like it.

But in PV2012, Lightroom assumes that blown-out highlights are a mistake, and automatically, without giving me the option to disable this, brings them back! Which is quite easy from a RAW image, so now I see detail where I do not want any:

So now the only way is to set “Whites” up (by perhaps +50 to +80 on the slider), or do a curve adjustment. The Whites adjustment gives me this:

The drawback is that now I need to do this manually, and that it does affect the rest of the image.

So here’s my tip: one way around this is to go back to PV2010, which you can do with individual images or with entire shoots. That way you get the old controls – and the old behaviour – back for the images you choose to handle this way.

When converting, you may want to convert to the new PV only on an image by image, or at least a shoot by shoot, behaviour.

Another way to “disable” the automatic conversion that has been suggested to me (but that I have not tried – it may take a little work to get to the same appearance as in PV2010):

1. Create a curve that is linear 1:1 from lower-left to somewhere close to upper right, and then curves straight up to the top.  You may need a few points to get this to stay straight below the curve.
2. Save the curve.
3. Import a fresh image or reset one that’s already in, and apply that tone curve.
4. Now create a preset that just has that tone curve.
5. Now, anytime you want to “disable” the automatic highlight recovery, just apply that preset.  You can do it to any number of images at once, even applying it on import.

And you should probably convert at some stage – Lightroom 4, although it has a few minor issues and is slower than LR3, is very good and has some compelling new features.

It’s out now (Thanks Jerzy for the tip). Link here.

I am waiting with my production system of course… a few days or longer until we see any issues. But I am upgrading as soon as I feel comfortable: on the laptop first.

An advanced computing tip today on speedlighter…:

Have a Mac or UNIX-like computer? Then you can use a simple little command to synchronise disks. Let me explain.

I have two hard disks next to the Mac. Two 3TB disks (I just upgraded them).  I work on one: all my images and Lightroom files and office admin files live there. Then I have the other.

Whenever I work, as soon as I am done on one and am sure it’s all good, I run the following command on my mac:

I.e. the following is the actual commands; the lines preceded by # are just comments:

rsync -a –verbose –progress –stats –delete /Volumes/MVW-3TB-1/Lightroom/ /Volumes/MVW-3TB-2/Lightroom/

rsync -a –verbose –progress –stats –delete /Volumes/MVW-3TB-1/MVW-Docs/ /Volumes/MVW-3TB-2/MVW-Docs/

rsync -a –verbose –progress –stats –delete /Volumes/MVW-3TB-1/Photos/ /Volumes/MVW-3TB-2/Photos/

The rsync command intelligently compares the two disks and adds anything to disk 2 that was added to, or changed on, disk 1, while deleting anything from disk 2 that was deleted on disk 1. A perfect backup in seconds (the first time can take a day of course, depending on how full your first disk is).

Using the nano text editor, I put these commands in a little text file called “syncdisks”, and I make that file executable using the chmod command (chmod 755 ./syncdisks). I then call that file by typing .syncdisks every time I want to run it.

I could automate further but this is good for me – and it shows the power of the command line, doesn’t it? Of course you would modify this to reflect the names of your disks and your folders to be copied.

(If this was all a bit techie for you, ignore this post and move on to tomorrow!)

In Lightroom, the catalog (the .LRCAT file) contains all your edits. But what if it gets corrupted?

In that case you can retrieve edits – eg edit the file in another app,like Photoshop – from small XMP “sidecar” files – IF you make these! This is off by default – turn it on in LIGHTROOM – CATALOG SETTINGS:

If that third tick mark is OFF in your Lightroom, then I advise you turn it ON right now!