Making black and white captures can sometimes be difficult. Especially if there are colors in the scene that you’d like to enhance with traditional filtration. The T2 does allow the capture of grayscale images through any of the 4 filter wheel apertures; clear, red (Wratten 25A), Green (Wratten 61) and Blue (Wratten 47B). There are many reasons why you won’t want to shoot grayscale images as grayscale. Shooting them in color is much more flexible.
Consider if you will, the ability to filter a scene after the exposure has been made. Consider using more than one filter, and consider applying any of these multiple filters on any reflectance you choose. Pretty cool you might say. How do I do it?
To start, let’s look at how a filter works photographically. Most photographers might surmise that a filter lightens scene reflectances of the same color but it doesn’t. Photographic filters absorb specific colors and pass specific colors. The colors that are passed efficiently are colors that are the same or similar in color as the color of the filter. The colors that are absorbed are colors that are complementary (or opposite) to the color of the filter. A filter cannot lighten its own color because all filters have some density, a filter cannot amplify, or manufacture, light. Filters work by absorbing the “other” colors. When the exposure is increased to make up for the absorption of light by the filter (that’s the filter factor), the color that is passed gets more exposure (because its not absorbed by the filter) than the absorbed colors (those that need extra light to be exposed properly).
The digital filter can be applied in RGB, in R, or G, or B. Additionally the “filter” can be applied as a selection, such as a product or object. Further, the “filter” can be applied as a curve, a selective color adjustment, a saturation adjustment or any other image editing edit possible. How do you make the right adjustment?
Begin by making a color photograph of the scene you’re interested in rendering to grayscale.
As soon as the capture is made, save the RGB to disk. The file can be edited most efficiently in Photoshop, so open the saved file in Photoshop. Using the Control Strip, click on the colored monitor icon and slide the cursor up to 256 grays.
Your image will be viewed as grayscale but it’s still an RGB. Edits can be made to each of the channels. You can make selections and edit the selections. View your edits as grayscale. When you are finished, make a mode change to grayscale; Image>Mode>Grayscale.
Save the file and name it differently than the RGB or you’ll overwrite the RGB. If you plan to take more than one image to grayscale, you may want to save the edits. Photoshop requires that you save the application of an edit before
This methodology is a real boon to those soft, pastel reflectances we need to separate when rendering in grayscale. Too often important values of different hue render the same grayscale value. Now you can filter each of the objects separately, by using a color channel. Add contrast with curves, add value with saturation, remove black with selective color. Experiment to hone this technique, it will come in handy whenever you need it.