How to Get Three RGBL Readouts, Plus an Image Tooltips Box Tip

by Andrew Darlow

One of the most important tools to have when prepping files is a RGB on-screen color value readout (a.k.a. floating densitometer). This is especially important when working on files with a lot of highlight or shadow data. As we get close to R255G255B255, we risk losing important image data, which can result in pure white areas in our files and prints. Conversely, as we get close to R0G0B0, we risk losing important shadow detail. Of course, this is image dependent, but in general, the two extremes are not favorable. Having the color value readout is also great for determining whether specific areas are neutral (RGB values will be equal in those cases).

Aperture gives us a few different options for displaying color value readouts. The first is at the top of the Adjustments HUD (circled in Red below - Fig. 1). The H key shows and hides the whole HUD. Anywhere your curser travels, an RGB and L value is displayed in real time. The L value represents the luminosity values from 0-100 (similar to the readout you would get from a grayscale image).

To reduce the number of dialog boxes showing, you can move the Adjustments HUD all the way down so that only the top part peeks above the bottom of your screen (see bottom right area of Fig. 2, circled in red).


Fig. 1


Fig. 2 - Image © Andrew Darlow

Another tool that does a good job of showing us an on-screen color value readout is the Centered Loupe. By choosing "Color Value" from the Centered Loupe's contextual menu (shown in Fig. 3, below), or by choosing View>Show Color Value in Loupe, you will see the RGBL values inside the loupe. I prefer to then set the Centered Loupe to "Focus on Cursor," so that it is easier to read precise areas. The "Focus on Cursor" option is also available from the Centered Loupe's contextual menu. Another feature of the Centered Loupe is that it can be moved quickly to the area of your cursor by holding down the carat/tilde key for about one second. The carat/tilde key (`) is in the top left hand corner of your keyboard. Thanks to Scott Bourne and some Inside Aperture readers for pointing that out a few weeks ago!


Fig. 3

Using just the Centered Loupe in this way gives you a very clean workspace, with the ability to move the loupe anywhere on the screen. In the screen shot below (Fig. 4), the Centered Loupe is set to the smallest allowable size in which the color value will still be displayed. Another interesting item is that if the referenced image is not online (the images below are just previews of archived photos), then a small alert message comes up inside the loupe that reads "not found." This is displayed whether or not the color value readout is enabled.


Fig. 4 - Image © Andrew Darlow

As you can see below (Fig. 5a), you can show both the Adjustments HUD and the Centered Loupe on screen at the same time (even in full screen mode), which can be helpful for those who use multiple and/or large displays, or for those who just want to be closer to their RGBL readouts.


Fig. 5a - Image © Andrew Darlow

But that's not all. How about three on-screen color readouts at once..that can't be possible! Well, yes it is. By choosing Window>Show Adjustments when not in full screen mode, a gray Adjustments window will appear "inside" the main interface. You can then add a floating Adjustments HUD that will mirror in real-time the adjustments made in the gray window. Then add a Centered Loupe and you've got the power of three (Fig 5b).


Fig. 5b - Images © Andrew Darlow

Another on-screen readout that gives us information is the Image Tooltips box (circled in red below - Fig. 6). The default behavior is for the Image Tooltips info box to pop up shortly after you rest your cursor on any image. The T key allows you to quickly display or hide this box. However, the esc key (top left corner of your keyboard) does something very similar. If you press the esc key while the Image Tooltips box is showing, it will instantly hide the Tooltips box. However, shortly after you move your mouse and pause, it will reappear. If you do a little "cha-cha" with your mouse by keeping it in motion, the Image Tooltips won't appear. For some people, this will be the preferred way of showing and hiding the Image Tooltips box. I'm still debating which way I like more. And while we're speaking about the esc key, it will also get you out of Full-screen mode (the standard shortcut is the F key).


Fig. 6 - Image © Andrew Darlow

Another interesting item to note is that when you are in Standard or Centered Loupe mode, the Image Tooltips box will not be displayed on top of your images.

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