There are times when I have a large number of images to process, and I need to do it quickly (or at least efficiently). I am at that point right now, having shot almost 3000 photos with my new Canon 30D and just thrown all of them into one project. Going through so many images in a reasonable amount of time boils down to locating chunks of similar images and comparing them against each other to pick the good ones. So how to compare as many images as possible at once?

First I make the workspace as big as possible. I go to Window > Layouts > Maximize Browser (option command B), press W to get rid of the project browser pane if it is still present, and press shift T to remove the toolbar at the top. Now the screen is full of thumbnails.

With hundreds of thumbnails on the screen it can make sense to arrange them into groups. If I'm going to compare pictures of a cat against each other then the job can be made much easier if they are all together, so either I drag them so they are adjacent, or even better select all the cat images and press command L to make a new album out of them.

But however I have these thumbnails arranged, if I have hundreds then they are too small for proper comparison. So I move the slider on the lower right all the way to the right to make the thumbnails as large as possible:

The large thumbnails are of a lower quality than the original, but it is possible to make judgements on them at this reasonable size. I can reject many right away by selecting them and hitting the 9 key.

To compare the images that remain I need more detail, and there are a couple of ways of doing this: Multi mode and Three-Up mode.

First I make sure I am in Multi mode:

Multi mode allows the viewer (and full screen view) to show multiple images at once. Primary mode shows just the currently selected image.

Then I select four adjacent images thumbnails that I want to initially compare:

By going to full screen with the F key I can make each fill almost a quarter of the screen:

To display more images I hit command left arrow or command right arrow twice, quickly. This scrolls the images up and down two at a time:

For a bigger view of one image, I can switch into Primary mode temporarily. Pressing option R fills the screen with the selected image. Pressing option U puts it back in Multi mode. To repeat with another on-screen image I click it and use option R, option U again.

Of course the loupe is always at hand, but can only look at one part of one image. No use for comparisons.

For even larger views, I use the zoom function. The disadvantage with using zoom is that with the limited VRAM on my machine (24" iMac with better graphics), going into zoom mode arbitrarily reduces the number of images from four to two or three, so losing my selection.

If four images is too many, how about three? There is another display mode called Three Up that I can use for comparisons:

To use Three Up mode, I select one image:

And then go full screen with F:

The selected image is in the center and the adjacent images are shown to either side. It's wasteful of screen space, but does the job. As I hit left or right arrow keys, the images scroll left and right. I can also click on the left or right images to make them scroll to the center.

To narrow down to just the center image and one other, I command click on the image I want. That adds that image to the selection and prevents Three Up mode from doing its magic. Command click on it again to restore the Three-Up display.

Pressing Z to zoom from Three Up mode gives me three full-size images that I can freely scroll around for comparison. Command space drag moves single images and shift command drag moves all of them together.

I've gone from roughly comparing hundreds of tiny thumbnails to comparing just three images in great detail. By rating or keywording I can pick the ones that I think are the best and then move onto another group of images.

Tags: Aperture, Comparing, Speed, Thumbnails