Swizerlan Would it be possible to incorporate ASTAP sensor tilt analysis into asi air plus to assist with correcting tilt and collimation?

If you want a turn key solution, you can use the tool in PixInSight.

You can do it manually on a budget by looking at the star sizes (HFD, FWHM, etc) at different locations of the frame. Many programs have tools to display star sizes. Even ASIAIR has a star size tool.

For a frame that has no tilt and no field curvature, all stars in the frame will have identical (to within 10% or 15%) star sizes. With field curvature, the star sizes at the corners will be larger than the star size near the center (i.e., same way as you adjust backfocus of a reducer). With decentered optics, the lowest star size will not be at the center of the frame.

With tilt, one of two corners will have larger star sizes that the remaining corners.

You can do better by using a Bahtinov mask and inspecting the focus of a star near the center, and compare with focus of the stars near the four corners. This method not only tells you there is a tilt, the Bahtinov mask will tell you the direction of the tilt (i.e., which direction it is off focus).

Unfortunately, star analysis will need a steady, clear night. The best way to adjust tilt (and very accurately) is to reflect a green laster pointer (any bright monochromatic light source would do) off your camera's sensor. Google for "cloudy nights sensor tilt green laser," and you will find lots of resources. (I use an OAG in the reversed direction to mount my laser, with the laser installed in place of the guide camera, and with the beam emitting from the prism towards the camera.)

If you really plan on adjusting the tilt of the sensor inside the camera, I also recommend getting one of ZWO's camera rings to mount the camera so you can have a steady platform to adjust the internal tilt.

But my real recommendation is to let someone with proper tools to do that kind of adjustment. Just adjust tilt with the tilt plate.

Chen

    w7ay

    I am well aware of the various tilt measurement solutions. I am interested in realtime capabilities
    like what you see here in this thread.https://www.cloudynights.com/topic/809050-tilt-discussion-astap/page-13#entry11745639
    I dont want to use a pc I would prefer to do this all from asi air in realtime. Tilt adjustments and collimation are difficult issues to tackle and real time feedback from a phone screen would be great. Seeing is not a huge issue unless its absolutely terrible even at zenith and you are oversampling

      Swizerlan I dont want to use a pc I would prefer to do this all from asi air in realtime.

      If you are going to use a PC anyway, why not attach the PC directly to the camera? There is no need to go through ASIAIR.

      Chen

        Swizerlan Thank you very much for your feedback, I forwarded this to our ASIAIR team, they will consider this in the future.

        4 months later

        w7ay i dont want to use a pc, i want to abandon the pc all together

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