Bryson Leidich

Photography |Photoshop | Fine Art Printing

Photoshop Essential Tools - Measuring Tools

There are six tools in the Measuring Group (I), two of which are valuable to photographers. Two others may be useful, and two can be eliminated until or unless you discover a use for them. The two primary tools in the group are the Eyedropper tool and the Color Sampler tool. The secondary tools are the Ruler and Note tools, and the ones I would eliminate from my toolbar are the 3D Material Eyedropper and the Count tool.

The Eyedropper Tool (I) serves to read the values of the pixel(s) under the tool, the area sampled being set with the Sample Size setting. This can be set to a number of values and the most useful is usually a 3x3 or 5x5 area which sets the size of the array surrounding the center pixel. Higher resolution files may benefit from samples from larger arrays chosen from the drop down list. A Point sample is of little value to a photographer as it samples a single pixel and may not accurately represent the color of the area. Adding the Shift key to the eyedropper and clicking on an area in the image sets the sample color as the foreground color.

The Sample options are to use the current layer, current and below, all layers and to ignore adjustments. If sampling a color becomes an issue for some reason, making a merged visible layer at the top of the stack can resolve the issue. A sample can be made which then represents the current state of the image. That merged layer can be turned off or deleted as suits your purposes. Merged layers can be valuable in making certain types of selections in addition to color, but you need to be careful of their location and visibility.

The Color Sampler Tool sets a sampler at the location you click so the color at that point can be referenced as you make changes to the image. Color samplers are numbered and show in the Info pallet. Up to 10 samplers can be placed in an image. In previous versions the limit was 4. In the Info pallet the means of reading out the color values can be changed to reflect the information you need, normally RGB, but there are others of use. Samplers can be dragged to new locations, or deleted using the Alt [Option] key with the eyedropper (Look for the scissors icon) or all deleted with the "Clear All" button in the options bar when the Sampler tool is active.

The Ruler (I) tools allow you to drag over a part of an image and discover the length of the line and the angle at which you drew the line. These show in the Info pallet. The height and width of a rectangle which would be created by the start and end points is also referenced. The Note tool simply allows you to put notes on your image at whatever point in the image you place the cursor. This is normally of greater value where images may be shared by more than one person, but can also be used as reminders. They do not print with the image.

The 3D Materials Eyedropper Tool samples information from a 3D image. The 123 Count Tool allows you to click on objects in an image and tallies a count of the clicks.