When adding a TIFF image to a View, the following error occurs:
TAG THRESHOLD=3 is ignored
The image is true black and white and has been saved as a gray-tone or color image.
TIFF images have a THRESHOLDING tag that lets you treat a black and white image as shades of gray through dithering and halftones. If the image is true black and white, the color and grey-tone threshold settings are ignored by ArcView.
Save the image as true black and white. This will set the THRESHOLD of the image equal to 1.
The error is a non-fatal error and occurs every time ArcView needs to
re-read the image.