MosaicPlanner

[Andres.Pozo]

Hi,

this is the announcement of a new script that I am finishing. The script is currently a beta that can be used for testing the capabilities of the script.

MosaicPlanner in a script for planning how many tiles are necessary for covering an area and finding the position and rotation of the tiles. The script can also help with the orientation of the tiles for getting good stars for off-axis guiders or double-sensor cameras.

MosaicPlanner is designed for PixInsight version 1.8.4 or higher. It requires an image that shows the area that needs to be covered with tiles. This image must have WCS coordinates that can be calculated using the script ImageSolver or other applications.



The user interface of the script has two parts: a viewer shows the reference image and the position of the tiles. To the right there are several collapsible panels that configure several aspects of the mosaic plan:

• Camera geometry: This section allows to configure the focal length and dimensions of the sensor of the camera that will be used to take the images. When the camera has an off-axis guider or a second sensor, the dimensions and position of the guiding sensor can be also configured.
  
• Mosaic definition: The mosaic is defined as a rectangular matrix of tiles where one of the tiles is considered as the reference tile. The mosaic will have several rows and columns of tiles around the reference tile overlapped by a certain amount. The reference tile is defined by the coordinates of the center and the rotation angle.
  
• Tiles: The list of tiles shows the coordinates of the current configuration of the mosaic. Each tile can be rotated by 90 degrees increments in order to fit a guiding star inside the guider sensor.
  
• Guide stars: The script can draw the position and magnitude of the stars on the image. The stars are extracted from local or online catalogs and can be filtered by magnitude. The objective is to show only the stars that can be used by the guiding equipment.
  

The user can move or rotate the reference tile and change the number of tiles until the requisites are met. The button “Generate” writes the tile list in the console and generates a new image with the mosaic plan drawn on the reference image.

LIMITATIONS

The algorithm for generating the position of the scripts is very simple and currently is only useful for mosaics with a focal length of 150-200mm or more. I will probably implement a better algorithm for shorter focal lengths but I have to think a little about it.

The plan is only as good as the precision of the data of the geometry of the camera. It is really important to set the exact effective focal length of the camera.



HOW TO INSTALL THE SCRIPT

• Download the script zip file
  
• Decompress the file in any empty folder of the computer.
• Enter the “Feature scripts” dialog of PixInsight 1.8.4 (Menú “Scripts | Feature scripts”) and add the folder where the script was decompressed.
• The script should now be present in the menu “Scripts |Utilities | MosaicPlanner”.
• Documentation
  

[msmythers]

Andres

This is going to be very helpful.


Thank You!


Mike

[Andres.Pozo]

Thanks Mike!

This is going to be very helpful.

I hope so 

[llpastro]

Andres,

How does one get an image of wide enough field with a know plate scale to use this script?

Larry

[msmythers]

Larry

The easiest way is use the Andres CatalogStarGenerator. Here is an example where I made a 7500x7500 image of Cygnus based on a 50mm lens. The screen dump shows the Generated image that I annotated on the top left. The top right is a zoomed in look. The bottom is the output of the MosiacPlanner using a 200mm lens with a sensor size of 3072x4608. I've included the MosaicPlanner screen shot showing it using the CatalogStarGenerator image.

Mike

[Andres.Pozo]

Andres,

How does one get an image of wide enough field with a know plate scale to use this script?

Larry

Hi Larry,

the easiest way for getting a reference image is what Mike has explained: generating a synthetic image using CatalogStarGenerator and AnnotateImage.

Other possibility is "googling" for an image of the desired area and solving its coordinates using ImageSolver. This method is more complex because solving wide angle images can be quite difficult. The documentation of ImageSolver has some tips for helping with this process.

Andrés

[llpastro]

The ImageSolver idea while more difficult may be better solution for what I was thinking.  I want an image that would show fairly well the full extent of a nebula so I could capture all of the outer edges.  The nebula would not show up in CatalogStarGenerator, right?

Larry

[Andres.Pozo]

The nebula would not show up in CatalogStarGenerator, right?

CatalogStarGenerator draws only stars. AnnotateImage can draw the asterism of the constellations and markers and labels of stars. For the Messier, IC and NGC catalogs it can draw a circle with the approximate dimensions of the object, but this is difficult for some nebulae.

[msmythers]

Larry

What this script has done for me is allowed me to use my 45mm lens shoots to plan for mosaics with my 1370mm 6RC scope or my 430mm refractor. The lens shot doesn't have to be perfect just show enough of the objects details for planning and be able to be image solved. That's much easier with a full resolution xisf image of my own then jpg from the web.

Here is an Orion shot of mine with the 6RC mosaic outlined on the image.

Mike

[llpastro]

Andres and Mike, thanks for the feedback.  I think I know how to proceed.

Larry

[Andres.Pozo]

Last summer I made a four tile mosaic for validating the algorithm of MosaicPlanner. The result is this image:

[Click on the image for full technical details in Astrobin]

[Andres.Pozo]

I have just published a final beta version of the script. It has a few bug fixes and small changes in the user interface.
The only significant change is the option for choosing between keeping all the tiles with the same rotation or adjusting the rotation in order to compensate the sky curvature. This compensation is only necessary for wide angle mosaics.

The effect can be seen in this image:


The new version can be downloaded using the link in the first post of this thread.

[msmythers]

Thanks Andres. The rotation will help nicely with my 45mm lens shots. Now all I need is some clear weather.


Mike

[goofisd]

I find this script very helpful, but a feature request if you're still tweaking it.

Is it possible to make the tile coordinates editable?

The situation I'm in is I imaged a target, and then noticed a feature that ran through it and the only way to fully capture it is to build a mosaic. But, I already have the first tile in place.  I eye-balled the second tile position, and needless to say I was a little more goofi than normal eyeballing it.   

A feature that allows me to adjust the tile positions would help a lot in planning coverage.

[Andres.Pozo]

Is it possible to make the tile coordinates editable?

The situation I'm in is I imaged a target, and then noticed a feature that ran through it and the only way to fully capture it is to build a mosaic. But, I already have the first tile in place.  I eye-balled the second tile position, and needless to say I was a little more goofi than normal eyeballing it.   

The coordinates of the reference tile are editable, so you can set the coordinates of your first tile and add rows and columns of tiles around it. Then you can fine-tune the overlap between tunes.