That sounds complicated enough (and ever-changing, as Tulon seems to be ongoingly addressing such issues in the current dewarping thread in the Scan Tailor forum) to require a separate test page.kasslloyd wrote:Do we want to test functionality of say content selection algorithms like in ST for the Mixed mode?
My logic for the predominance of the b&w images (they are four copies of a photo, not a painting, if that matters) was two-fold: 1) b&w images are more common in books, due to the expense of color printing and 2) just my barely educated guess, b&w is better for determining even lighting, because human brains translate colors as lighter/darker in ways not always related to their lightness/darkness, still, as I say, jsut a guess. Thus, for the two reasons, in a choice of the b&w image or a color image spread more predominantly around the test page, I chose the b&w. Btw, a good feature of this particular b&w image is that it goes from near complete white (the shirt collar) to near complete black (the nearby tie). I understand that is a good feature of images being used to test photographic range.kasslloyd wrote:if it's just to test the quality of cameras and resulting books then pictures would be good like those, but also maybe an actual modern color picture over old bw/paintings.. A very dark one where black extends to all the borders and a very light one where white extends to all the borders, to see how it handles the two, imo.
A third, more minor, rationale for more b&w than color image on the page square-inch-wise is that color is not as reproducible as b&w. We have settled on the test page *not* needing to be true to some given original, since we a) per Daniel's last post, don't care that much about that to begin with, and 2) want to accommodate people printing the test page on their own, with inevitably varying results quality-wise. But, taking those two criteria as given, I think we still would like a printed test page as common to all of us participating in this electronic community as possible, and my guess is that b&w is more likely to be similarly produced than color will be. Thus a b&w-dominated page will overall be more similar as produced around the country (or world) than otherwise.
Whatever we decide on the issue of the predominance of color vs. b&w on the test page, the nature of the images remains an issue. I selected the b&w image on the basis of a vague idea about the needed characteristics of a b&w image for the defined testing purposes (all contributions on that score welcome). But I can't say the same for the color image. I just picked it because it seemed to have lot of different colors. Kasslloyd, can you say more about the benefits of the two kinds of color images you are proposing?