Log Book Entry No.14

Days, Calendar Created: 12 Sep 2013 19:57:01 Days, Calendar Last Revised: 19 Sep 2013 15:31:38 Person PedroPaiva Text Test of Python Telescope Control

After turning telescope on, it successfully received GPS signal and did not started the usual RA movement.

The Camera was connected to Python via MaximDL
Telescope and Focuser connected to Python via the POTH Hub
Coordinates in agrement between Scope, Python and Stellarium

Target was set to be -0.1║ RA from current telescope position and Python SlewToTarget was tested.
Telescope moved the right amount and stopped, both telescope and Python alerted when ready.
A second test was made with +0.5║ RA. Also successfully.

Still with small (-0.1║ RA/DEC and +0.5║ RA) movements, Python SlewToCoordinates was tested successfully.

With the tests done, the telescope was moved to Vega via controled movements on Stellarium
Vega was inside the Camera Range, demonstrating that the Park Method works.
Vega was recentered (-0.01 on RA) and the telescope was manually synced.
During this test, movements as small as 0.003║ on RA proved to have no effect whatsoever.

The next step was to test the focuser and the camera.
First, while still on continuous mode of the camera, the Python-Focuser connection was tested.
Python can read the position and move the focuser. Units are steps. 1 step = 20Ám

Having confirmed that one can move the focuser with Python, Vega was taken out of focus to test if we could focus the star using a small

step = -2000
new = 100
i = 0
prin = True
while abs(step)>50:
    old = new
    val = []
    for j in range(3):
        cam.Expose(0.1, 1)
        while not cam.ImageReady:
            if prin:
                print 'Step:', step
                prin = False
        ap.load('test', ap.var.usrPath+'testImg.fit')
        m = ap.fitBrightest('test', fixAngle=True)
    new = mean(val)
    if new > old:
        step = -round(step/2)
    while POTHFocuser.IsMoving:
        if not prin:
            i = i+1
            print 'Image:', i, '  psf:', new
            prin = True

and it's Python
Image: 0  psf: 100
Image: 1  psf: 5.52986378126
Image: 2  psf: 4.7682139585
Image: 3  psf: 4.63297472825
Image: 4  psf: 4.53466837512
Image: 5  psf: 4.42683230931
Image: 6  psf: 3.50235534344
Image: 7  psf: 3.18247227685
Image: 8  psf: 2.31374459737
Image: 9  psf: 2.59153415468
Image: 10  psf: 1.1543044854
Image: 11  psf: 4.32859550035
Image: 12  psf: 4.57442264323

which can be used to generate the following plot:

During the tests, a cloud covered the target but the time was enough to show that the script still have room for improvement and can work.

Telescope was parked and disconnected.
Camera was also disconnected.
Everything was turned off and covered.

Back to: LogBookAstronomy

Subject Test of Python Telescope Control
Status thumbs-up

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Topic revision: r4 - 19 Sep 2013 - PedroPaiva

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