Log Book Entry No.14

Created: 12 Sep 2013 19:57:01

Last Revised: 13 Sep 2013 12:44:42

PedroPaiva

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 -0.1º 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 +0.5º RA. Also successfully.

Still with small (-0.1º RA/DEC and +0.5º 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 0.003º 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 = 20µm

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

script script

step = -2000
new = 100
i = 0
prin = True
while abs(step)>50:
    old = new
    time.sleep(0.5)
    val = []
    for j in range(3):
        cam.Expose(0.1, 1)
        while not cam.ImageReady:
            if prin:
                print 'Step:', step
                prin = False
            else:
                time.sleep(0.1)
        cam.SaveImage('c:/Users/dome-pc/desktop/development/pythonscripts/astropy/new/userdata/testImg.fit')
        ap.load('test', ap.var.usrPath+'testImg.fit')
        m = ap.fitBrightest('test', fixAngle=True)
        val.append(m.values['sigy'])
    new = mean(val)
    if new > old:
        step = -round(step/2)
    POTHFocuser.Move(step)
    while POTHFocuser.IsMoving:
        if not prin:
            i = i+1
            print 'Image:', i, '  psf:', new
            prin = True
        time.sleep(0.5)

output. output.

Image: 0  psf: 100
-2000
Image: 1  psf: 5.52986378126
-2000
Image: 2  psf: 4.7682139585
-2000
Image: 3  psf: 4.63297472825
-2000
Image: 4  psf: 4.53466837512
-2000
Image: 5  psf: 4.42683230931
-2000
Image: 6  psf: 3.50235534344
-2000
Image: 7  psf: 3.18247227685
-2000
Image: 8  psf: 2.31374459737
1000.0
Image: 9  psf: 2.59153415468
1000.0
Image: 10  psf: 1.1543044854
-500.0
Image: 11  psf: 4.32859550035
-125.0
Image: 12  psf: 4.57442264323
-32.0

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.

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