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proposal - script shooting hooks

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Offline lapser

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Re: proposal - script shooting hooks
« Reply #90 on: 17 / March / 2015, 12:40:07 »
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http://chdk.setepontos.com/index.php?topic=7934.msg105252#msg105252

We found a timing related problem on the G1X where it appears that another task was modifying the raw buffer. It happened with my time lapse script in single shot, but not in continuous mode, and only when the exposure time was >1 second. We never figured out what caused it, but I was able to work around it by always running in continuous mode.

It's possible that some of the Canon image processing settings are triggering the other task to modify the raw buffer. In my case, I think it may have been related to high ISO noise reduction that was an advertised new feature on the G1X.

One thing I thought about, but never looked into, was if somehow the base raw buffer address was incorrect. That might be worth looking at for your problem.

I also remember a timing issue in capt_seq_hook_set_nr(), which is where I put my pre-shot delay. I had to do the delay right at the beginning, before it calls set_nrflag(). I doubt if this is related to your issue, though.
EOS-M3_120f / SX50_100b / SX260_101a / G1X_100g / D20_100b
https://www.youtube.com/user/DrLapser/videos

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Offline srsa_4c

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Re: proposal - script shooting hooks
« Reply #91 on: 17 / March / 2015, 13:17:28 »
If you're suspecting placement issues with the raw hook, moving it to developseqtask could be a possibility (only done in the sx170 port, see this year's posts in the porting thread).

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Offline reyalp

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Re: proposal - script shooting hooks
« Reply #92 on: 17 / March / 2015, 16:53:01 »
One thing I thought about, but never looked into, was if somehow the base raw buffer address was incorrect. That might be worth looking at for your problem.
I am very confident the failed shots are correct image data with the shutter closed, because I see the same hot pixels and noise as I see in a normal dark frame. The meter and histogram also see black level rather than 0.

If there's a timing issue, it's something causing the part of the firmware that controls the shutter to behave abnormally.

I initially dismissed this as hardware failure, since it is clearly connected to the mechanical shutter, but this seems untenable given that some yield and debug draw settings reliably show a 0.5%-1% failure rate, while others show no failures over tens of thousands of shots.

I could just throw in one of the workarounds that makes it go away in my script, but assuming it is really a side effect of the hook usage, I'd like to have better understanding, because it will probably affect other users too.
Don't forget what the H stands for.

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Offline c_joerg

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Re: proposal - script shooting hooks
« Reply #93 on: 19 / March / 2015, 05:45:56 »
Hello,

I have not really everything understood, what you have talked about the last days. Yes I’m still a Rookie…

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We found a timing related problem on the G1X where it appears that another task was modifying the raw buffer. It happened with my time lapse script in single shot, but not in continuous mode, and only when the exposure time was >1 second. We never figured out what caused it, but I was able to work around it by always running in continuous mode.

I made a test with my G1X last day. I run rawopint.lua which is not in continuous mode. All Canon RAW pictures with exposure time  >1 second and  >= ISO400  where OK. Can there a difference between CHDK DNG Files and Canon RAW Files?

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may have been related to high ISO noise reduction that was an advertised new feature on the G1X.

Can this switch off with CHDK?
Unfortunately with exposure time from 4s the Intervall can be faster than 10s.
On my EOS1200D I can switch it off in the Camera.
For my S110 and G1X I found no Camera Menu…


About my last Test with G1X and rawopint.lua:

https://www.youtube.com/watch?v=QRid9lNPFOA

1) I found differences between ISO Values in the log File and EXIF Data. The Last Picture in the log File has ISO800, which I expect, but EXIF Data has ISO1600. In the EXIF Data there is a jump between ISO400 to ISO1000. I found no ISO800 in EXIF.

2) This is the first time, where I had flicker with your script. I analyzed the JPG pictures in the following way:
I calculated  A  = (R*0.3 + G*0.59 + B*0.11) for every Pixel. Then I calculated a mean Value for all pictures and plot these values (flicker was around picture 360). Interesting results for me:

- Flicker was only at ISO320 (The last runs on S110 where only until ISO200)
- look at the zoom plot around picture 360, how continually the progress off the mean value is…This is not random. The steps look like 1/3 EV steps.

Do you have the possibility, to analyze your EXIF data, when you had the flicker? May be there are also concentrated on some ISO values….

May be that is stupid what I am thinking now.
When I wrote my script I notice, when I made set_tv96_direct(xxx), that the Camera rounded this to an APEX value in 32 steps. Then I had problems on some other point. But from that time I rounded the value in 32 steps before I wrote it to the camera, I had no problems anymore. May be that has nothing to do with the problem.

ISO works in steps to?
Who do you make this with the ISO values? You write not rounded values true?
But how is the ISO function realized in the Camera. I think it is just an amplifier.
Can it be that not every step is realized?

So when this is a problem, I can see it when I run isoinc until ISO400?
On my last test I stopped around ISO200…

« Last Edit: 19 / March / 2015, 08:17:22 by c_joerg »
M100 100a, M3 101a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd


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Offline c_joerg

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Re: proposal - script shooting hooks
« Reply #94 on: 19 / March / 2015, 05:54:05 »
The zoom plot...
M100 100a, M3 101a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

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Offline reyalp

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Re: proposal - script shooting hooks
« Reply #95 on: 19 / March / 2015, 16:26:36 »
Looking at your log, I see the "meter" starts jumping at row 351. Two possible explanations
1) ISO override doesn't behave as expected in this range. e.g. script sets 320, but the camera uses some other value. Running isoinc over this range might give some useful information. You can get the range from the sv96 values in the log.
2) The raw buffer used for the meter contains some garbage instead of raw data. Saving CHDK raw might show if this is the case. I think this is less likely, because the meter still shows a trend.

What ISO setting did you have in the canon firmware?

I've attached my own plot of the log.
Don't forget what the H stands for.

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Offline c_joerg

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Re: proposal - script shooting hooks
« Reply #96 on: 19 / March / 2015, 17:03:56 »
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Looking at your log, I see the "meter" starts jumping at row 351.

Did you find something like this in your logs when you have flicker?

 
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The raw buffer used for the meter contains some garbage instead of raw data. Saving CHDK raw might show if this is the case.

I saved Canon RAW Data. Does this data comes from an other buffer as the CHDK RAW?

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What ISO setting did you have in the canon firmware?

It was set to ISO100.
M100 100a, M3 101a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

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Offline reyalp

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Re: proposal - script shooting hooks
« Reply #97 on: 19 / March / 2015, 17:23:51 »
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Looking at your log, I see the "meter" starts jumping at row 351.

Did you find something like this in your logs when you have flicker?
When I see flicker, the change is much smaller, only a few APEX96 units. Yours are much larger, 60+ units. On yours, the under_frac also goes to zero. Interestingly, it stays 0 after the flickering ends.

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I saved Canon RAW Data. Does this data comes from an other buffer as the CHDK RAW?
It should be the same, but they aren't necessarily at saved at the same point in the process, so the buffer could be corrupted by the time CHDK sees it. Bugs in CHDK might also cause CHDK to use the wrong buffer.
Don't forget what the H stands for.


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Offline c_joerg

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Re: proposal - script shooting hooks
« Reply #98 on: 20 / March / 2015, 16:12:23 »
I run isoinc from 500 to 730. I found all ISO values from ISO200 until ISO1000 in the EXIF data. No jump. I think everything is ok?
Should I run next time G1X with CHDK RAW?
M100 100a, M3 101a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

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Offline reyalp

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Re: proposal - script shooting hooks
« Reply #99 on: 21 / March / 2015, 14:46:52 »
I run isoinc from 500 to 730. I found all ISO values from ISO200 until ISO1000 in the EXIF data. No jump. I think everything is ok?
Thanks for testing. Seems like ISO control is actually working so something else odd was happening when you got the flickering.

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Should I run next time G1X with CHDK RAW?
It might provide some additional clues.
Don't forget what the H stands for.

 

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