Continuation of the bright center background gradient investigation and optimization of comet 220P/McNaught observations on Vespera telescopes. The Vespera telescopes have a Mosaic mode whereby images greater than the sensor size can be created. It does this by taking a series of overlapping images and combining them into a single larger image. For this night’s observations I had the telescopes do a regular (non-mosaic) observation, the default size mosaic, and the minimum size mosaic observation of comet 220P/McNaught. The default mosaic size is different for each type of Vespera telescope, and the minimum size is the field of view (FOV) area of the sensor.
The results are shown in the unedited, “straight out of the telescope” (SOOT) JPG images below and are available in my PhotoShelter gallery. Click on the i below the slideshow to see the caption with the Manual Target parameters.
Again, the center gradient is not present for the Vespera 1 images but is visible with the other telescopes. I kept the total observation time around 15-20 minutes to minimize the motion of the comet relative to the stationary stars. This is much less than the recommended 2+ hours and is not enough time to complete the mosaic. The background gradient at the overlaps is not smooth. Next time I will investigate the different object types (nebula, galaxy, and cluster).
Leave a Reply