Hello, I've made my first attempt following the directions you posted, and got through everything quite easily. It was a rather large stack of 265 images, so some steps took fairly long, and I got out of memory errors, but it still processed and made a master of my final stack. However, now that it's all done, I'm looking at the quality, and have a gradient that didn't get removed (due to moon light), and I can't seem to stretch it that will with the histogram as it is. I'm used to using a histogram that has a Dark, Mid, and White point, and only moving the mid and dark points to stretch without blowing out the stars.
See attached image.
Also, here's the same image processed in the traditional applications.
(http://astrob.in/319722/0/rawthumb/gallery/get.jpg?insecure) (http://astrob.in/319722/0/)
The Flatten Background adjustment estimates the background level using either a plane or a higher-degree polynomial surface. By default it uses a plane surface. Did you also try with the other settings? Also, since there is a lot of nebulosity in the image, you may need to lower the rejection sigma for these images.
Right now you can indeed only adjust the black and white points.
I'm having some trouble getting match to work. I've had it work on only a handful of images from the stack, but it will not work on the final stack, nor can I get it to work with a new set of images that I stacked (13 images). Also, because the dialog resets and closes on fail, you have to redo the search parameters again to start over. It would be more convenient to have it fail back to the match settings, so you can adjust, and make another attempt.
Could you please share the two stacked images (exported as FITS) using DropBox (share with the support email address), and a selection of images for which it works and for which it doesn't? That way I can include them as test cases for the matching improvements of the next maintenance release.
Good point about not closing the dialog when matching fails. I'll change that.
I sent the e-mail.
I'm also wondering if there can be a preference "process stacks automatically" that can be turned off.
I found when clicking around next to stacks, sometimes I click one, and then it begins processing with no way to stop it. If it's a large stack (in my case 265 images), it sits there for about an hour before I can get out of it, or force quit the app. So a preference to stop processing, or being able to hit the 'esc' key to abort a process would be helpful. If you had a preference to turn off automatically process stacks, you could add a right click option to "process now" for the stack.
Thanks.
Thanks!
The "Stop Tasks" button in the toolbar or keys ⌘. will stop the processing. It will do that gracefully, so it may take a few seconds.
I just loaded the two stacked images into Observatory, and had no trouble matching them. The steps I did were
- Select image and choose Match.
- Reset it to its default settings if needed (bottom right button).
- Enter name of object (Heart Nebula, and Pacman Nebula) and choose the top object from the list.
- Because both images cover a large field of view, I then unchecked "Frame size" and moved it back one notch. This makes the plate solver only use the center 75% of the image.
- I clicked the Match button.
In both cases it was successful right away using the built-in Tycho-2 catalog. I had to match them individually, because they are of different objects. Could you please try again?
Worked great! Looks like I just didn't understand all the settings and how they have an effect on matching. Thanks!