On Mon, Sep 12, 2016 at 02:35:25PM +0000, Erika Callagon wrote: > I want to do a Mutual Crop on my VSI .dat images to remove lateral shifts > between the two images. I have successfully done this with other data, but > I don't know why it I can't do it for the two new images that I have. When > I go to 'cross-correlation', the 'Correlate with' drop down option is > disabled (the other options are active). The images are taken with the same > setup, and should have the same dimension of pixels.
For correlation the images do not need the same pixel dimensions. Instead one pixel must represent the same area in both (otherwise the correlation makes no sense). In other words, the ratio of physical size in metres and pixel resolution must be the same for both images. You can make the images compatible by resampling one (presumably that with larger pixels) using Scale. It only changes the pixel resolution, leaving physical dimensions intact. If you did that and the images still do not seem compatible you can use Match pixel size in Dimensions and Units to enforce equal pixel sizes. Only do this after you ensured the pixel sizes are equal, but some minuscule differences possibly remain due to rounding. Regards, Yeti P.S.: The other two compatility conditions for Mutual Crop are that the dimensions and values have the same units for both images – but I suppose you do not have problem with that. ------------------------------------------------------------------------------ _______________________________________________ Gwyddion-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/gwyddion-users
