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Re: Single step mode

Posted by karenacollins on May 14, 2019; 6:15am
URL: http://astroimagej.170.s1.nabble.com/Single-step-mode-tp1152p1155.html

Hi Tiffany,

The special auto-operation of Multi-Aperture within DP unfortunately doesn't currently support single step mode. However, I can see that that mode could be useful and will add you request to my to-do list.

In the meantime, you will need to work around the issue in one of four ways:

1) If the images are plate-solved and have a WCS solution in the FITS header, turn on "Use RA/Dec to locate aperture positions" and the apertures will now follow the stars in the shifting images and you will not need Single Sep mode. If the images are not plate solved, you could do that in AIJ. That could take some time, but you can turn it on and let it run while you are doing something else. Be sure and update to the latest "daily build" version of AIJ, single an update was made to address a timing out problem.

2) To save time in the plate solve process, if you have the latest daily build version, you can simply plate-solve the first image, and any other image that have a large jump (or even the image after a meridian flip). Enable the "Use RA/Dec to locate apertures" option and siable "Halt processing on WCS or centroid error" (both in the Multi-Aperture set-up panel). Then the apertures will follow the RA  and Dec positions when RA and Dec are available, and will assume the same position as the previous image if the current image is not plate solved.

3) If the images are not plate solved, use the "Stack Aligner" icon above the image display and use a larger aperture on well isolated stars to align the images. Then run photometry on the aligned image stack.

4) I think this option is what you are trying to do in the last paragraph, but maybe the second option mentioned below is enabled. For this option, first calibrate the images in DP (but do not run multi-aperture photometry), then load the calibrated image stack into AIJ and run Multi-Aperture directly. Single Step mode should work when running Multi-Aperture directly. Be sure an disable "Allow aperture changes..." in the Multi_Aperture set-up panel so that the images will automatically advance (the option directly under Single Step). If the "Allow aperture changes..." option is enabled, you will need to right click (or equivalent on a Mac) to advance to the next image in the sequence.

Karen