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Capturing shutter value

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Capturing shutter value
« on: 02 / February / 2019, 07:13:25 »
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I hope someone can comment on a frustration I have with some Lua scripting.


The issue is that my script first registers the shutter setting and it does this OK if, and only if, I explicitly do a half shutter press outside of the script first.


If I do this explicit half shutter press then adjust the shutter speed without doing a half shutter press the script will not pick up the adjusted shutter setting, it just uses the previous half shutter setting.

BTW if I change the aperture, this is OK, ie the script picks this up without the explicit half shutter press.


In my script I use the following, which I thought would solve the problem, but it doesn’t.

click("shoot_half")
s = get_tv96()

As I say, I hope someone can comment.


Cheers


Garry
« Last Edit: 02 / February / 2019, 07:35:31 by pigeonhill »

Re: Capturing shutter value
« Reply #1 on: 02 / February / 2019, 10:12:47 »
Try this :

Code: [Select]
press("shoot_half")
repeat sleep(50) until (get_shooting() == true )
s = get_tv96()
release("shoot_half")

Your code does not wait for the camera to set exposure and focus when you call the click( ) function.

Ported :   A1200    SD940   G10    Powershot N    G16

Re: Capturing shutter value
« Reply #2 on: 02 / February / 2019, 10:13:57 »
Ok I think I ‘solved’ it. Used get_user_tv96.

Re: Capturing shutter value
« Reply #3 on: 02 / February / 2019, 10:16:30 »
@waterwingz

We crossed on postings.

I did try a delay, but not an intelligent one like you suggest.

Thanks for the hint.

Cheers

Garry


Re: Capturing shutter value
« Reply #4 on: 02 / February / 2019, 10:38:50 »
Ok I think I ‘solved’ it. Used get_user_tv96.
I suspect that is not doing what you think - it's just returning whatever tv96 override value you set (or the Tv setting that will be used if the camera is in M or Tv Priority modes).  It's not telling you what Tv value the camera will use when setting exposure in P or Auto or Av priority modes.

@waterwingz
I did try a delay, but not an intelligent one like you suggest.
When I use that method, I also include a counter so that the loop "times out" if the camera is unable to set focus or exposure.  I left that out for clarity in my example code.
« Last Edit: 02 / February / 2019, 10:44:05 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Capturing shutter value
« Reply #5 on: 02 / February / 2019, 10:44:35 »
@waterwingz

Good idea.

In my use case, in my landscape focus bracketing script, I’m in manual focus mode.

The only thing I need to capture is the incoming Tv and Av, so I should be ok, but will put a time out in for robustness.

Cheers

Garry

 

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