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INDI Library v1.8.4 Released

Minor bugfix release with some highlights:

Fits Viewer - Background pseudo ADU

1 week 4 days ago
kcobby
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Fits Viewer - Background pseudo ADU #51028
Is it possible to create a feature that allows the user to select an area within an image in the fitsviewer to give a targeted opportunity to critique background psuedo ADU e.g a moveable box of say 100x100 pixels that shows the user some appropriate stats. The mean/min/max of the 10,000 'background'pixels could be a useful value to quickly determine exposure. The Fitsviewer currently produces DN values for the whole image so why not for a user selected area. Maybe link said feature with the cursor over the image.

Skywatcher 190MN - EQ6 Pro (with Belt Mod) - ASI1600MM-Cooled - ASI EFW7 - ASI120MM - WO f4 Guide Scope - Rigel nStep - KStars/Ekos - KDE - PixInsight

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1 week 2 days ago
rmor51
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Fits Viewer - Background pseudo ADU #51157
I agree absolutely with this request. In order to determine the right exposure, we have to compare the standard deviation of the background into a capture to the same value into an offset. The capture value must be within 3.5 and 5 the offset value. So we have to select an area of the image background. Today I have to load the two images into Iris software to do that. It would be convenient to be able to do so with Kstars.

Thank in advance.

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1 week 2 days ago
kcobby
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Fits Viewer - Background pseudo ADU #51170
That's an interesting factor to determine correct exposure. When you say within '3.5 and 5' what parameter are you evaluating?

Skywatcher 190MN - EQ6 Pro (with Belt Mod) - ASI1600MM-Cooled - ASI EFW7 - ASI120MM - WO f4 Guide Scope - Rigel nStep - KStars/Ekos - KDE - PixInsight

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1 week 2 days ago
rmor51
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Fits Viewer - Background pseudo ADU #51174
You mesure the standard deviation (sigma) of a background area in capture and offset.

Sigma (image)~3.5 to 5 sigma(offset)

Try 1, 2, 3 or more minute exposition and examine the sigma against an offset. It is not needed to overpass the value 5.

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1 week 1 day ago
DerPit
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Fits Viewer - Background pseudo ADU #51224
I assume with 'offset' you refer to a dark? Indeed an interesting way of doing it. It seems to boil down to the standard approach of 'swamping read noise', using the dark/offset STDEV as read noise?

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GPDX+EQMOD, CEM60EC, ASI1600+EFW+ASI290 mini

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1 week 1 day ago
rmor51
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Fits Viewer - Background pseudo ADU #51229
The right word is BIAS I think. Not dark.

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