Comet Alignment Problem

[GrantBoxer]

Hi All,
I have taken a series of 50 images of Comet Lemmon, which is up in our southern skies at the moment, and when I try to intergrate these after using the Comet Alignment module, I get a horizontal line of comets. It appears as thought the program is working only in one axis. Any thoughts or suggestions?
I have used the batch pre-processing script to do the image calibration and debayering but note that the images do have their date and time stamp intact.
Regards Grant

[Ignacio]

Hi Grant,

I have used that module several times lately with no problem. Did you click on the comet's core for the first and last image in the sequence? Did you check (by opening the in between images) that the interpolation went well?

Ignacio

[GrantBoxer]

Yes, I checked the intermediate images and they seem to been registered OK. I think it is in the Integration step where I am having problems. I am using the standard intergration tool. Is that correct?

[Ignacio]

Yes. Make sure that the output files from comet alignment have the comet core registered at the same (x,y) position.

Ignacio

[nmontec]

Is there a tutorial anywhere for processing the comet and using this script?

thanks
Nicola

[astroedo]

Probably a stupid question 

Are your images star aligned before doing comet align?

Bye

[RoStm]

Hello,

I too have a (beginner) problem with CometAlignment:

I'm just yet a newbie with PI and want to learn dealing with the CometAlignment tool. When I start with "Add Files" I get the message *** not found DATE-OBS in file ... (FITS file of course).

Looking into the headers of the corresponding files, I clearly can see the correct entries under keyword DATE-OBS.

So what is going wrong here? Can someone please give me a helpful hint?

Thanks,
Rolf Stadelmaier

[pfile]

are you running under 1.8? the javascript engine has changed from 1.7 to 1.8 and some scripts do have problems. i guess you can test this by downloading 1.7 and seeing how the script behaves there.

i've used this script under 1.7 successfully but have not tried on 1.8.

rob

[RoStm]

Yes, I'm running under 1.8 and your suggestion obviously is right.
Now after going back to 1.7 CometAlignment is loading the pictures correct.

Hopefully the author of this script will bring it into line the next time?

Thank you for clearing this up,
Rolf

[RoStm]

Now it becomes rather strange to me.
I went back to PI 1.7 a second time to have a picture for documentation issues. But there is no longer a CometAlignment script available. At least I could'nt find it again. Has there changed something in the meantime or is it me? 

Thanks,
Rolf

[astroedo]

UH!! 


Anly an idea: Try to reset the Pixinsight settings using the shortcut in the start menu.

Warning you will loose all the customizations like tool bars position recent files and so on.

Ciao

[pfile]

Now it becomes rather strange to me.
I went back to PI 1.7 a second time to have a picture for documentation issues. But there is no longer a CometAlignment script available. At least I could'nt find it again. Has there changed something in the meantime or is it me? 

Thanks,
Rolf

sometimes PI can lose track of the scripts. it's fairly easy to add a script back into PI. but you have to know where the scripts are in the filesystem and for windows, i don't know where they live. on the mac the scripts are inside the application bundle.

[RoStm]

I want to warm up this topic (CometAlign not found DATE-OBS ...) some few.

By chance I tried to load up older pictures with the CometAlign tool (running PI 1.8  RC7) and to my surprise this was successful. Analysing this behavior brought up that different entries for the keyword DATE-OBS is causing this odd result.

I'm using the ccd camera Atik 314L+ and in former times I did image acquisition with the proprietary software Artemis Capture. Later on I changed to AstroArt 5.0. The difference between the two keyword entries for DATE-OBS is that AA5 writes the seconds of the observation time with fractional digits whereas Artemis Capture writes plain seconds. So this must be the reason why the CometAlign tool doesn't find DATE-OBS in the corresponding image files captured with AA5.   

FWIW,
Rolf

[GordonH]

I had the same issue with version 1.8. I capture images using CCDSoft and it writes the DATE-OBS entry with decimal seconds (nnn.ddd) I manually edited the entries leaving only whole seconds. That corrected the problem. Now to figure out how to make CCDSoft leave of the decimals in the first place!

Gordon

[cwiede]

Hello,
I took some images of comet Brewington a few days ago and encountered the same problem. I use a SBIG ST8-XME with CCDSoft. The time in the fits-header has decimal seconds and Pixinsight says that it can't find the DATE-OBS data for the comet alignment. Is this problem not yet resolved? Are there any suggestions how one can batch-remove the decimal part of the time?
Christof