PixelAlley

Tips and Tutorials


How to Convert an Image to Black and White
to Check Values


Written by Jinny Brown

Question:

How can I convert an RGB (or CMYK) image to B/W to check values?


Response:

Corel Painter only works in RGB so there's no CMYK or true greyscale available. However, you can convert the image to Greyscale in Photoshop if you need to.

Here are a couple of ways you can simulate greyscale in Corel Painter, using a Clone of your working image. See the original image below.



In Painter IX.5, Painter X, and Painter X.1:

1. Use File > Clone.

2. With the Clone active, use Window > Show Underpainting.

3. In the Underpainting palette's Style drop down list (Painter IX.5) or the Underpainting palette's Photo Enhance drop down list (Painter X and X.1), choose Black and White. If you want to keep the Clone image in "greyscale", click the Apply button. See the result below:



In Painter IX, IX 9.1 and IX.5; in Painter X and X.1; and in earlier Painter versions:

1. Use File > Clone.

2. With the Clone active, use Effects > Tonal Control > Adjust Colors.

3. Move the Saturation slider all the way to the left.

4. Click the OK button. See the result below:




After changing the image to "greyscale" using the two methods above in Corel Painter, I made two Color Sets from the resulting images and in both cases, the Color Sets contained 60 colors ranging from black to white:



The result when changing the Mode to Greyscale in Photoshop 7:




If you want to avoid going back and forth between Corel Painter and Photoshop just to check values, I think the methods suggested above for Corel Painter should do the trick
. You'll need to test the methods yourself as this example image has a limited number of values and using your images, the results may be different.


© Jinny Brown
September 6, 2007