Exposure issue

[Pswoboda1]

Seems like the exposure time is arbitrarily changing during the night.

Attached is a screen shot of the images when it changes. Not sure if the moon rising is causing it.

I may have a setting wrong.
Any suggestions the best exposure settings for night mode?

Thanks,
Pat

[NiteRide]

Non-expert feedback:
Sounds like here you are just looking for tips on "consistent" exposure ("best" exposure really depends on your objectives and your conditions).
I am not an expert on this, but there are a lot of variables at play that determine how the camera exposes. The settings for exposure and/or gain, mean target, night to day transition time, just to name a few. Also, you didn't really say when this is occurring (early evening? middle of night?) Or similarly, if you have had lots of luck before and this is just starting, or if it has happened consistently over time. etc
I know for me the first block of night/evening exposures are always brighter as the sky becomes more and more dark - this doesnt seem to matter for startrails and doesn't have much impact either on the timelapse so I personally don't really worry about it.

I am pretty sure there are more than a couple threads in the discussions already talking about the histogram and light sensitivity, maybe check those too? just search around. for example search for "exposure" or "moon" but lean more on ones that are more recent than ones discussing much older versions of allsky software (eg this recently-ish on histogram) :

• Question about Exposure and Gain settings #3583

I'm sure you will also get another reply or two, but the above is a place to start. especially in terms of providing more detail and context to help get you a better answer. 😉

[EricClaeys]

@Pswoboda1, do you know roughly when this happened?
Can you attach /var/log/allsky.log and I'll take a look at it.
The brightness shouldn't change that much, unless a bird sat on the dome...

[Pswoboda1]

Eric,

Attached is the allsky.log and a pic with the exposure fine and the next image that goes dark.

Appreciate the help,
Pat
allsky.log

[EricClaeys]

@Pswoboda1,
I can see in the log where it was taking 10 second images then switched to 100 ms images, for no apparent reason.
Before trying to debug that more, please increase your "Max Auto-Exposure" values for daytime and nighttime. They are both 100 ms, so I'm not sure why it ever took 10 second images at night.
For daytime Max, I suggest 5 seconds. For nighttime, you should use at least 10 seconds. Many people use 60 seconds for a max, but that's up to you.

After making that change, let it go a couple nights and see what happens. I suspect the problem you saw is related to a low max.

[Pswoboda1]

That's exactly what is happening.
And did it again last night.

I'll make your suggested changes and let it run a couple days then let you know.

Thanks!