images shown in slices by ximtool

[marclg83]

I recently installed the X11IRAF using the installer (Intel 64 bit) in a Mac laptop with Big Sur 11.7.8. IRAF works great (i.e., apall, imcombine, imarith, splot...), however, the ximtool displays only a section of 512x512 pixels if I attempt to use the imexam or display tasks.

I looked at the ximtool help and found that a different size can be defined by creating an .imtoolrc file in my home directory. Following the instructions I create this file and add the following line inside:

1 2 2048 2048

As a result, when I display an 2048x2048-pixel image, the tool shows slices of the image as the attached screenshot. I tried with different sizes in the .imtoolrc file, but it is always the same result with the exception of the 512x512 size, which shows a clipped version of the image.

Might you have any clue on what's going on here? I guess it's a stupid mistake, but I cannot figure it out. Thank you very much in advance for any help that you could provide!

[olebole]

Creating a local imtoolrc is usually unnecessary and dangerous, because its entries must match the assumtions IRAF has about the device. Specifically your single line makes the first configuration of ximtool as a 2048x2048 image, while IRAF still assumes a 512x512 image, which results in the image you ave shown.
The default imtoolrc already has several image buffers pre-defined, so there is no need to re-define them. It is enough to set the stdimage variable in IRAF to the 2048 one:

ecl> set stdgraph=imt2048
ecl> imexam myimg 1

However, the use of SAOImageDS9 may be the better choice, as this program is much more flexible than ximtool.

As this is not a bug, I moved it into the discussion forum.

Finally, if you are just going to start using IRAF: It is not recommended to start new projects using IRAF nowadays, unless it is really unavoidable IRAF is an old package without institutional support and a shrinking user and maintainer base. Instead, it is really better to use f.e. the Astropy ecosystem which is already a good alternative for many use cases instead of investing time into a depcreated software tool.