Jerry Sedgewick

Color Integrity: Is What You See What You Saw?

Introduction To microscopists, the image is everything. Th e fundamental reason we establish Koehler illumination in light microscopy is to optimize resolution and contrast, setting a baseline so that our images are reliable, consistent, and comparable. However, the microscope is only the front end of an imaging system. Is there a better way to standardize the color we see in the digital image so that it more consistently and reliably matches what we see in the microscope, especially for bright-fi eld images from colored specimens? An answer to this question would not only reduce the potential for missing critical information in conventional color bright-fi eld images [ 1 ] but could be especially important when using metachromatic stains where biochemical properties such as a change in pH can dramatically aff ect the color.

Creating Pseudocolored Images in Photoshop

Photoshop Jerry Sedgewick University of Minnesota sedge@Limn.edu The method for creating pseudocolor in Photoshop can be done in few steps, but the image will not be colored in the conventional way. The conventional means for producing pseudocolor comes by using a look up table (LUT). This LUT is an overlay for making a range of colors according to choices provided by the software. The colors are matched to levels of brightness and darkness in the image (grayscale pixel values), typically from a short to long wavelengths. In that scenario, violet colors are matched to the black and near-black pixels and red to those dose to absolute white. Blue, yellow, green and orange become the mid-range pixel values.