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INDI Library v1.9.8 Released (29 Sep 2022)

Bi-monthly INDI Library released with new drivers and bug fixes.

iOptron iPolar focal length

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Does anybody know what is iOptron iPolar polarscope focal length ?
It helps Stellarmate settings for polar adjustment.
...Lasse...

PS. pixelsize 3.75 um, 1280*960, FOW 13° but focal length ???
2 years 9 months ago #46733

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Can you post a star field you took with the iPolar? Then we can solve it and get the focal length from it.
Jasem Mutlaq
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2 years 9 months ago #46970

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Replied by Bart on topic iOptron iPolar focal length

Hi, the Field Of View (FOV) of the long side of the detector is different from the short side of the detector. You only need to know one FOV in order to find the focal length, but you need to know which one exactly.

From there it's simple geometry. The focal length is:
FL = Detector / 2 * tan( FOV / 2 )

For example: With a FOV of 13° along the short axis of the detector (0,00375 mm * 960 pixels = 3.6 mm) the focal length would be 16 mm.
if along the long axis: 21 mm.

Cheers, Bart

I was wondering Jasem, is it possible to use a small DIY telescope in stead of a iPolar in the iPolar software?
Latest Stellarmate on Rpi 4B, 294mm-pro, EFW-8, CEM70
2 years 9 months ago #46973

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Jep.

I asked from iOptron support team end their answer was 25mm.

...Lasse...
2 years 9 months ago #46976

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