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I have a longslit spectrum that I'm trying to take spatial cuts of. That was simple enough, I changed the dispersion axis and used 'apall' to get my cuts. However, the units and orientation are wrong. Orientation would be simple enough to fix by editing the original image, but I can't manage to flip the axis or change the x-axis coordinates of my "spectra" in any way. imcopy, scopy, dispcor, all failed when I tried setting w1=30 w2=0 (trying to flip the axis and change scale). In splot, I can use 'p' to flip the axis, and it works fine, but then if I switch between apertures using () it crashes with a segmentation fault. Also, I'd like to change the x-axis units from pixels/angstroms to AUs. In principle, I think I could manually go through each cut and use splot's p, save the file, and then use hedit to change the units, but should there be some simpler way? And... why is it that "scopy a b w1=100 w2=0" (for example) doesn't flip the x axis of my spectrum?Finally, is there any way to flip spectra/change axis units, scale in spectool? The :coords commands all did very strange things when I tried them, none good or effective, and they only worked on one spectrum at a time.Thanks,
Adam

Hi Adam,I need a little clarification. There is often confusion about whether someone is refering to a physical image file or a graphics display. So when you are "trying to take spatial cuts" do you mean physically extract the pixels to a file or just graph the spatial data? Also what is it you are trying to do in the end. If it is to view and an graphically analyze it then maybe even if you intended to extract the pixels you really only want to be able to graph the data.I am also not clear if the coordinates you want along the spatial axes are pixels or some conversion to arc seconds?Before going on I need to also tell you that tasks like SPLOT will automatically display axes with increasing coordinate values independently of the order of the pixels in the file. You must then use the cursor commands to flip things.Let me start by getting to where you can view the spatial cuts of a 2D images (presumably calibrated with LONGSLIT.TRANSFORM). I would use SPLOT (let's skip SPECTOOL for the moment). Run SPLOT and then type ":dispaxis N" where N is the image axis for the spatial dimension. This will then start showing you spatial cuts where the "aperture" is the line/column number. Note you can also interactively set "nsum N" to sum spatial lines/cols (or you can set these in the package parameters). Now you may still be seeing wavelength units because the reductions may not have placed units information for the spatial axis. To get rid of this go to pixels with '$'. To flip this use the combination 'w'+'f'.There well may be a bug with the 'p' option for assigning a new scale but let's get there later.So let me know more precisely what you want and if my description of viewing spatial cuts is not enough for your needs.Yours,
Frank