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Asteroid labels, custom xeph, for video

Karen F
in PixInsight
I intended to make a video for the recent flyby of 2013NK4.   I'm satisfied with my first video except for the label of the asteroid.     When I used the asteroid downloaded files as input to render (custom catalog, xeph files) a label, that label is not in the right place.   I wanted to put that label on every frame perhaps using the image container, but the location of the asteroid from the downloads is not right and not over the asteroid.    I assume these orbits need to be updated.   I made I picture to show the difference from where the asteroid is (with painting-annotation) , and the label location  with the "+" is from script-render-annotateimage.      

is there a way to get a correct location label from render?   

Comments

  • BlockHeadBlockHead
    Karen,

    You are bumping up against reality here. You are seeking to apply a label who positional accuracy has uncertainties! I am guessing (though I do not know for certain) that an interaction with the Earth will certainly alter the orbit of this asteroid in such a way it could not be calculated to the kind of precision you are expecting from ephemerides (orbital parameters) generated many months ago.

    If you want to know there is a reason I suspect you can compare the output of PixInsight positions with something that likely more up-to-date like JPL Horizons.

    As a practical matter you can certainly move the label in the frames that make up the animation you are constructing. This could be tedious. You can also simply create your own label on each frame (easy in Photoshop)..but still tedious. 

    This isn't a way to force a better calculation given the XEPH files you have... this is the fundamental issue and these files are updated by PixInsight on a semi-yearly basis as far as I know. 

    One last thing...I will tell you the Adam Block solution... of course I have not done it... but it should work in principle. If you align the images on the Asteroid using CometAlgnment... this will put the asteroid in the SAME position for every frame. You then just need to paste the label you make in the same position on each image (this is easy to do in Photoshop manually or with actions). Then you will align images again but this time based on the stars using StarAlignment. Viola! Now you will have labels that move with the asteroid in your animation.

    -the Blockhead 
  • Karen F
    Ok,  I suspected that the asteroid position would have uncertainties.  My video now just has the paint label at the very first png file.   I will work on a new video, putting the asteroid at the center of the field of view using the cometAlignment.    
    thanks


  • Karen F
    Here is the new video.   I wish I could get a galaxy or something interesting for an asteroid to pass through. 
    I gave the Adam Block classes credit on the Facebook page.



  • BlockHeadBlockHead
    I want to see!
    (You might have your FB content only shared with friends or a specific group...I can't see and did not have a mention notification.)

    So you aligned on the asteroid?
    That is great..
    -the Blockhead
  • Karen F
    Oh too bad you can't see it.  everyone gave me great comments.   But after looking at the video again, and realizing that I have compressed the time of 4 sec frames down to .1 sec display in my movie, I wondered if there is a way to pull the timedate stamp out of the header and past it to the bottom of each image, so it shows the flow of actually time..   Do you have an idea or method?   I am going to fix the link so you can see the aligned video.   

     I will post it in the PixInsight beginners group since I think you are in that group.   
    I mentioned your classes....    thanks
  • BlockHeadBlockHead
    Really well done on the video!
    I do not know an easy way to get the timestamps in there.
    Actually do I know a way, but it uses Python programming. 
    Non-trivial.
    -the Blockhead
  • Karen F
    Oh.. I will ask my son about it.  He uses python and maybe he will want to impress me.  Maybe, there will be a great script/tool in PixInsight in the future.    There are so many cases  for time-lapse label such as eclipse, star trails, meteor showers,  rotating sun images.   Maybe some super nova that dims over a month.  Time stamping would be so cool.    

    Thanks!
  • BlockHeadBlockHead
    With astropy you can access the FITs header.
    Then when you have string (datetime object) you can convert to an image of the timestamp and finally insert into the image. Not much fun THere probably is an easier way.
    -the Blockhead
  • Karen F
    Thanks.  I will discuss with my contacts.  They might be inclined to help me out.  

     I had another asteroid flyby which had a tiny galaxy near by.  I have been trying to bring out the galaxy in the new video.    Anyway, I have been playing around with elliptical masks and gradient masks.   I downloaded the process "Perfect_galaxyMask1"  from your website which is a solid mask and it works fine.   I was trying to recreate the gradient elliptical mask you demo'd in one of your videos.   I can't find that video.  I keep looking in the mask section and I can't seem to find that section so I can read the equation and watch it again..     My pixelmath version will create a gradient eclipse, but as soon as I start rotating it, the position jumps. It's not lining up with my offsetx and offset symbols.   90 deg will be right where I want it, rotate to 45 degrees and the x and y don't line up with my input offsetx and offset.  It's making me very frustrated.  My formula must be missing something.     Could you put the working pixelmath/process on your web site?     I have uploaded my  Karen_Galaxy_mask.xpsm to google drive.    as soon as I figure out how to share with you I will put a note back here.  If you can look at it maybe you can see what is wrong.
    Thanks



  • Karen F
    Adam,
    please when you can look at my pixel math 'Karen_Galaxy_mask.xpm"   and tell my what I am missing in my elliptical gradient mask,     (it only seems to work with 90 degrees!).  
    Thanks

  • Karen F
    Update.   it's kinda working.  But I don't understand how the offsetx and offsety work.    Once I get my fuzzy ellipse on the image,  I can move it by  adding/subtracting to the offsets to move it around.   I thought I could get my origin for the ellipse by using x/y from my cursor but that doesn't work.    The angle change from 90degrees changes how x & y should be input.    
  • BlockHeadBlockHead
    OK... I guess I need to see some screenshots to see what you are doing.
    But, today (unlike years ago) you can now use the GAME script to draw your ellipses and things.
    Have you given this a go??

    -the Blockhead
  • Karen F
      I was logging on to delete my confusing set of comments!   Obviously I need to rewatch something,   
    I did  find that video  on the gradient ellipse,  but I'm still not getting it.  
     I haven't looked at the GAME script yet.  I will give that a go.   

    This is my first attempt to do something with masks for my own data.     I'll give it a go..

    Thanks
     
  • Karen F
    WOW.   That was a lot easier.    I have my mask.  Now I will try and use it.    Thanks

  • BlockHeadBlockHead
    Yes, the GAME script uses that expression I came up with. 

    But here is the important part. I think you were watching the video on this page:

    Please be certain to read any text I write above the videos. In this case, you would have been made aware of the GAME script (for which there are many videos covering this).

    Thanks,
    -the Blockhead
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