CHROMiX

Sampling images in ColorThink Pro

Hi

When I open an image of for example a ColorChecker, the image is in the right orientation and the sample dropper picks up the colours correctly. However, the multiple sample mechanism, when set to ColorChecker, generates a list which is not in the usual order, or at least not the order that Measure Tool uses. The list goes along the rows rather than down the columns. Is there an option I am missing to create lists with the x and y inverted?

Secondly, when I open a Reference file created in Measure Tool, the image has the right aspect ratio of horizontal to vertical squares, but the colours go the wrong way, with x and y inverted. But further, in this case if I use the sample dropper on the image, it picks up the colour that should be in the square rather than the one that is shown.

The issue of the reversed x and y for the sample dropper also happens for lists created by ColorThink, eg the list of gamut boundary coordinates you get when option double clicking a gamut entry in grapher, so it is not just a compatibility issue with Measure Tool Reference files.

Am I missing some option here or is it a bug. I am using version 3.0.1b20.

Incidentally going back to the ColorChecker case, the colours I read in from an 8 bit Lab image have integers for the a and b values as expected but the L values aren’t exact multiples of 100/255 as I would expect. As an example, one entry has an L value of 38.15 in ColorThink whereas I’d expect the value to be 38.04. Is that an inaccuracy and is there a reason for it?

Thanks Nigel

Yep, it looks like you’ve found a bug there.
I believe certain colorlists are hard-coded to fit a certain orientation. From the looks of this, I’d say the eye-dropper tool has its x / y orientation switched around.

Steve might have more to say about this, but he’s on his way to a trade show this week.

Thanks for bringing this up, and I will create a feedback report for you describing this issue.