Quote:
Originally Posted by Logieberra
Peter, how do our TheSkyX HalfFluxDiameter HFD figures correspond to FWHM? The same? If so, in the burbs of Canberra, I never see below 3. Evenings start at mid 5's and get marginally better over time.
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Hi Logan,
I normally don't pay much attention to the HFD in TSX as I use FocusMax. Generally I find the HFD after using FocusMax is higher than the FWHM values I see when inspecting the images in CCDInspector which of course uses actual scope resolution in the calculations.
For example after focusing Ha the average HFD from FocusMax = 3.99
The range of FWHM over 7 images 10 min guided CCDInspt = 1.96-2.13
So, perhaps a 50% reduction. I'm not sure how the HFD value is calculated in FocusMax. Perhaps I have not set something up in the software properly but I have not found anywhere to set in the imaging scale.
Peter