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Old 06-12-07, 17:12
Don Hoey's Avatar
Don Hoey Don Hoey is offline  
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Join Date: Dec 2005
Location: Norfolk
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As promised.

To check the movement of Control Points including Black/White/Neutral I resized an image to 2000 wide. I then added a grid at 100 pixel spacing.

Three crop zones were added.
The crops were actually done on the white grid to ensure they were in exact units x 100 pixels. The colour marks being just inside the grid.

Control points were used in these samples, but tests show Black/White/Neutral points behave in exactly the same way when a crop is done after they have been placed. All movement of points on the image is a result of the selected crop.

These show quite conclusively that the points reference the top left of the image. On a crop all points maintain a reference to that position and do not move radomly.

Images attatched.

1) Resized copy of the test target.
2) Placement of control points on the uncropped image.
3) Yellow Crop
4) Green Crop
5) Purple Crop

Don
Attached Images
File Type: jpg Grid test resized.jpg (135.1 KB, 2 views)
File Type: jpg Control point placement.jpg (117.1 KB, 3 views)
File Type: jpg Yellow Crop.jpg (91.9 KB, 4 views)
File Type: jpg Green Crop.jpg (103.8 KB, 3 views)
File Type: jpg Purple Crop.jpg (105.2 KB, 3 views)
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