May I have an answer please: Yes, not or may be ? Thanks.

Is there anybody out there ?

It's not exactly clear. What are the exact steps & forumale needed to estimate the optimal exposure.

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.

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?

4- the area must be with any stars.

Perfect.

Hi Jasem,

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

What's going on about this item please ?
Robert

No progress, perhaps it will be worked on for 3.5.8

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

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.

No news ?

Hello, I have been working on this issue and I wanted to ask which particular statistics were relevant to be displayed while calculating the stats of the desired area.