Nautical Dawn/ Nautical Dusk

Discussions, Bug Reports and Issues related to Beta versions of SharpCap
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DocHighCo
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Nautical Dawn/ Nautical Dusk

#1

Post by DocHighCo »

Hello Robin,

it looks like the "Repeat until ..." step calulates for nautical dawn and nautical dusk the same time - both nautical dusk. Can you maybe check?

Best Regards

Heiko
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Re: Nautical Dawn/ Nautical Dusk

#2

Post by admin »

Ooops, yes, too much copy+paste when writing that code.

Will be fixed in today's update.

cheers,

Robin
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DocHighCo
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Re: Nautical Dawn/ Nautical Dusk

#3

Post by DocHighCo »

Hello Robin,

I tried again a few days ago. It seems the error is still there with the latest version. Nautical dawn and nautical dusk give the same time.

Regards

Heiko
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Re: Nautical Dawn/ Nautical Dusk

#4

Post by admin »

Hi,

that's not what I'm seeing (see screenshot below - look in the log).

Note that in the example shown, waiting for nautical dawn completes immediately - this is deliberate. The condition is taken to be satisfied at the first point in time (starting from now) that the distance of the sun above/below the horizon satisfies the relevant condition. Since when I ran this test the sun was already higher than -12 degrees, the nautical dawn condition is satisfied immediately. I thought long and hard about this behaviour and in the end decided that a step that would wait until the next night if asked to wait for astronomical darkness when it was already dark would be a very bad thing...

thanks,

Robin
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DocHighCo
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Re: Nautical Dawn/ Nautical Dusk

#5

Post by DocHighCo »

Hello Robin,

nautical dusk above at 23:41:00 seems about right. But nautical dawn at 19:39:00 seems a bit late.
For me I get nautical dusk at 11:45:00 p.m. (that's about right). But nautical dawn is at 02:19:00 p.m.. Shouldn´t that be a.m.?
Maybe some problem with the time zone or the longitude settings? At least nautical dawn and nautical dusk don't give the same time anymore.

Regards

Heiko

PS: I am at 4.0.7944.0
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Re: Nautical Dawn/ Nautical Dusk

#6

Post by admin »

Hi,

that was the point I was trying to make - when I ran the test (at 19:39:00) the sun was already above -12 degrees altitude, so the nautical dawn condition passes straight away.

The 'Wait Until Event' step deliberately does not wait until the next occurance of the event specified - it waits until the earliest future time where the altitude of the sun satisfies the inequality that defines the event (apart from noon/midnight).

Waiting until the next moment that nautical dawn happens might seem the correct thing to do, but actually is pretty useless as if you run your sequence 5 minutes after nautical dawn you will end up waiting nearly 24 hours. If you really want the next nautical dawn event, wait until midnight then wait until nautical dawn.

thanks,

Robin
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DocHighCo
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Re: Nautical Dawn/ Nautical Dusk

#7

Post by DocHighCo »

Hello Robin,

I am still confused. You mean if I want to start a sequence that should run until nautical dawn at let's say 23:40 and nautical dusc is at 23:41 I can't do that because SC will set nautical dawn to 23:40 and end immediately? I would have to wait until 23:42 because only then nautical dusk is behind me? Is it the same for astronomical dusk and dawn - or civil?
It is clear to me that you would check the -12° condition for nautical dawn in the morning before sunrise. But the next evening after sunset when you would normally start to image for a reason or another before astronomical, nautical or civil dusk? Does this make sense? In the evening to check the -12° condition for dusk would make sense and in the morning for dawn in my opinion.
In the evening after sunset all "wait until" and "repeat until" steps until xxx dawn could be allowed and in the morning after sunrise all steps until xxx dusk. I think the problem is that dusk/dawn-conditions are checked for a day running from midnight to midnight. I don´t know if this could be checked for the 24h period running from midday to midday.
A "wait until" and repeat "until step" that considers date/time would also help to avoid confusion.

Best Regards

Heiko
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Re: Nautical Dawn/ Nautical Dusk

#8

Post by admin »

Hi,

yes, you are correct - if you specify 'wait until nautical dawn' and run the sequence just before nauticul dusk, the wait will complete immediately as the sun is currently higher than the nautical dawn/dusk threshold.

My reason for this is mainly the idea of 'wait until astronomical dark' waiting 24 hours if you run it just after astronomical dark - someone would miss a night's imaging, which is unforgiveable. I think it's better to err on the side of starting now and maybe having to reset later than on the side of waiting 24 hours when perhaps it was not intended.

There is already a wait until <time of day>.

cheers,

Robin
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Re: Nautical Dawn/ Nautical Dusk

#9

Post by DocHighCo »

Hello Robin,

I don't see it from the "wait"-point of view. More from a practical point of view. I am thinking about doing something in a loop until a certain time, dawn etc.. before I stop. So, what if I want to start taking sequences of exposures or livestacks in a "repeat until" loop just before nautical dusk and end it at nautical or astronomical dawn or at another specified time? I couldn´t do it with the sequencer at the moment, right?
I just can run the "repeat until"-loop after nautical dusk until nautical dawn or after astronomical dusk until astronomical dawn. I can never start before in the same night.

Regards

Heiko
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Re: Nautical Dawn/ Nautical Dusk

#10

Post by admin »

Hi,

here's a real example where I think the current behaviour is important

Code: Select all

SEQUENCE
    LOOP 10 TIMES
        WAIT UNTIL EVENT NauticalDusk
        LOOP UNTIL NauticalDawn
            CAPTURE 100 LIVE FRAMES
            DELAY 10
        END LOOP
    END LOOP
END SEQUENCE
Under the current behaviour, if you run this at any time of day it will image as soon as it becomes dark (including if it is dark already).

Can you share an example script that would benefit from your behaviour please so I can consider it. Maybe we could have a WAIT UNTIL NEXT NauticalDawn or similar?

cheers,

Robin
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