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INDI Library v2.0.7 is Released (01 Apr 2024)

Bi-monthly release with minor bug fixes and improvements

measure of the background

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In order to determine the minimum exposure, we have to measure the sigma (std dev.?) on an offset and on a light : Sigma light>= 3.5/4 sigma offset.

No problem with the offset and statistic tab. For the light we would be able to draw an area on the view image, without stars, and get the statistic result.

Thank you to consider this wish.
Last edit: 2 years 4 months ago by MORELLI.
2 years 4 months ago #77643

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Replied by MORELLI on topic measure of the background

May I have an answer please: Yes, not or may be ? Thanks.
2 years 4 months ago #78162

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Replied by MORELLI on topic measure of the background

Is there anybody out there ?
2 years 4 months ago #78633

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It's not exactly clear. What are the exact steps & forumale needed to estimate the optimal exposure.
2 years 4 months ago #78637

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Replied by MORELLI on topic measure of the background

Hello Jasem,

The rule to fix the MINIMAL time exposure is:
Std_dev of a light background must be at least 3.5 time the std_dev of a biais.
So no problem for the biais, we have to measure the std_dev of an area without star on a light.
This could be done on the view image.
The exposure time is increased until to reach the 3.5 value.

Today, we have to get a light capture and do this measure into a software like Siril or Pixinsight.

Best regards.
2 years 4 months ago #78643

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1. Capture bias frame.
2. Measure std deviation of whole frame.
3. Take light frame
4. Probe 100x100 pixels area and measure std deviation.
5. Repeat #4 until std_dev is 3.5x bias frame value

That's how it goes?
2 years 4 months ago #78645

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Replied by MORELLI on topic measure of the background

4- the area must be with any stars.

Perfect.
2 years 4 months ago #78646

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Replied by MORELLI on topic measure of the background

Hi Jasem,

First I wish you an happy new year for you and yours relatives.

What's going on about this item please ?
Robert
2 years 2 months ago #79530

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No progress, perhaps it will be worked on for 3.5.8
2 years 2 months ago #79551

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#78643 said "without star on a light".
Should this (#78646) read "the area must be without any stars" ?
2 years 2 months ago #79621

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Replied by MORELLI on topic measure of the background

Hello Jerry,

Yes the area must be without start.
We have just be able to zoom into the image and draw a right box.
I think you are going to automatize this function. It is not mandatory on my thinking.
Juste a possibility to draw a box into the image and obtain its statistic would be great.
2 years 2 months ago #79625

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Replied by MORELLI on topic measure of the background

No news ?
1 year 11 months ago #82393

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