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CDK12.5 defocused stars tests

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#1 Rouzbeh

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Posted 04 May 2021 - 12:14 PM

Been setting up the CDK12.5 with initial collimation and tests.

 

 

 

Collimated and moved the same star to the 4 corners of the APS-C sized chip.

 

Center looks good, poisson dot visible.

 

4 corners have aberrations when defcosed (outward), looks ok when in focus.

 

I am assuming this is normal (not sure)?

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Edited by Rouzbeh, 04 May 2021 - 12:34 PM.

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#2 Rouzbeh

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Posted 04 May 2021 - 12:30 PM

Center looks good.

 

Slight bulge looks like tube thermals (again not sure)

 

Will try again after a few hours of the fans on and heaters off  (RH was 85%)

 

 

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#3 Rouzbeh

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Posted 04 May 2021 - 12:31 PM

180s subs also look ok with round stars

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#4 Rouzbeh

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Posted 04 May 2021 - 12:34 PM

Another one with 180s

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#5 Rouzbeh

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Posted 04 May 2021 - 12:34 PM

Another one with 180s



#6 lucam

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Posted 04 May 2021 - 01:32 PM

Rouzbeh, if you haven't yet, check out the PI Wavefront Estimator script to quantify Zernicke coefficients for on-axis aberrations given images of defocused stars. It's a pretty powerful tool!

 

Luca


Edited by lucam, 04 May 2021 - 01:33 PM.

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#7 Rouzbeh

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Posted 06 May 2021 - 10:57 AM

Rouzbeh, if you haven't yet, check out the PI Wavefront Estimator script to quantify Zernicke coefficients for on-axis aberrations given images of defocused stars. It's a pretty powerful tool!

 

Luca

I haven't used that yet. 

Will look into it, thanks!




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