About ATV.PRO
 

Contents:


Introduction.

Back when I started using IDL a lot, around 1998, one thing I wanted which didn't really exist at the time was an interactive image-display tool optimized for viewing astronomical CCD images.  There are a lot of nice image viewing programs out there, like SAOimage , which are usually designed to work with IRAF or as stand-alone applications (see here for a list of other image viewers), but for working in IDL it would be far easier to have a display routine written as an IDL procedure.  In order to learn how to use IDL widgets, I started writing an image viewer which would do some of the things I wanted.   It seemed like something that would be useful to other IDL users, so I made it available here.  The program is written entirely in IDL.  It's very easy to use within an IDL session and it's also very simple to add new routines, buttons, menus, or whatever.   It looks a lot like SAOimage or DS9, so if you're used to using those programs, then you'll probably get used to ATV quickly.  

For detailed instructions on how to use atv, see the instructions page .

ATV version 3.0 requires IDL version 8.0 or greater.  If you are still using an IDL 7.x version, you can still use the older 2.3 version of ATV that's posted on this site, but you will likely find incompatibilities and funny behavior related to recent updates to the IDL Astronomy User's Library.  Upgrading to IDL 8 is highly recommended.

One nice thing about ATV is that you, the user, can easily add new features or link your existing IDL programs to ATV.  For example, you can easily define a keyboard shortcut that will pass the current cursor position in data coordinates to an external IDL routine.  Also, all of the ATV internal variables are stored in common blocks, so you can have another program access the ATV variables by declaring the ATV common blocks in your program.

I have been told that as of late 2015, ATV will work with GDL, if GDL is compiled with the wxWidgets library. I haven't tried this myself, but this may be useful as an option for those who don't have an IDL license.

What atv can do for you.

A quick list of ATV's main features:

In comparison with some other image viewing applications, ATV has some nice features:


Currently known bugs, problems, and workarounds.

Since I don't have all that much time to debug and test ATV, it's likely that there are some bugs hidden in the program which I haven't discovered yet.  If you find a bug, send me an email and tell me what went wrong, and please be as specific as possible about what you were doing and what IDL version and platform you're running.  Currently known bugs in ATV or general IDL issues that affect ATV are listed below.

August 2020: Problems reading FPACK-compressed FITS files? ATV can read in FPACK-compressed images, if you have the funpack routine installed as part of a cfitsio installation. Make sure that you've installed the funpack executable in a directory that's part of your PATH so that IDL can find it.  If the unix/linux command "which funpack" returns a valid path to the executable, then IDL should be able to use it.

One problem that can come up is that the IDL Astronomy User's Library FITS-reading routines will automatically recognize a FITS file as FPACK-compressed if it has the .fz suffix. However, if the file is missing the .fz suffix in the filename, there isn't a simple way for IDL to automatically detect whether the file is FPACK-compressed or not. If you have an FPACK-compressed image whose suffix is just ".fits", then ATV won't be able to read it directly. I'd like to find a way to fix that, but for now the quickest workaround is just to rename the file to add the .fz suffix. That is, change the filename from "image.fits" to "image.fits.fz" and then it should read in properly. This can be an issue for images coming from a variety of sources, like the Subaru HSC public data release for example. If you have a compressed image that you can read in with DS9, but ATV won't read the image, this is what might be happening, and it's just that ATV doesn't know how to automatically recognize the image compression without the ".fz" suffix.


November 2016: Fix for MacOS XQuartz Widget Problem:  In the most recent update to XQuartz (version 2.7.10 or 2.7.11), something happened that causes IDL widget programs to crash IDL completely. The symptom of this problem is that if you try to run ATV or xloadct or other widget programs, you'll get an error message saying "Error: attempt to add non-widget child 'dsm' to parent 'idl' which supports only widgets", and your IDL session will crash.  The fix for this problem is explained here:
http://prod.lists.apple.com/archives/x11-users/2016/Oct/msg00030.html

The short version is that you need to issue the following two commands at the terminal prompt:

sudo mv /opt/X11/lib/libXt.6.dylib{,.bak}
sudo cp /opt/X11/lib{/flat_namespace,}/libXt.6.dylib

After that, widgets seem to work fine again. Thanks to Phil Appleton for diagnosing this problem and pointing out the solution.


Other bugs/issues:

If you are having trouble getting ATV to work, here are the first things to check:


Known issues.

These are peculiarities of the program that can't really be classified as bugs.  Some have to do with inherent limitations of IDL widgets, and others have to do with how IDL behaves differently under different platforms.



Disclaimer.

This software doesn't come with any warranty.  It may contain bugs.   Please bear in mind that this program is a work in progress, and it is gradually being updated and improved, but I don't have a whole lot of time to work on this.

The photometry and spectral extraction routines in ATV are intended primarily for quick-look analysis and not for publishable results.  They work very well in many circumstances but users should be aware that they are not as sophisticated, or as rigorously tested, as some other available tools for photometry and spectroscopy.

Comments, complaints, suggestions?

If you've tried atv and have any complaints, comments, bug reports, or suggestions for further improvements, write to me at barth [at] uci [dot] edu.    I don't promise to add every feature that people request, but I do keep a list to keep track of suggestions and I try to handle bug fixes relatively quickly.


Last updated August 5 2020
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