Fastest continuous shooting, motion detect, focus (IXUS 300 HS)

Fotoni

9

« on: 29 / July / 2013, 05:16:22 »

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I have been testing some scripts from CHDK wiki and fastest ones are unreliable. They either work fully, skip one or more RAW but save all JPGs or crash the camera randomly after a few shots. Fast HDR scripts work about same speed too, but it is really weird that sometimes all shots are done fast and sometimes it just crash. I'm using latest stable CHDK build for this camera.

Code: [Select]

for i=1, n, 1 do
   ecnt=get_exp_count()
   press("shoot_full_only")
   repeat
      sleep(20)
   until(get_exp_count()~=ecnt)
   release("shoot_full_only")
end

Slower ones are reliable when saving the files, but delays between shots might vary a lot and generally they are slower than just keeping the shutter button down manually in continuous drive mode. Well, manual pressing is out of question because I need to shoot without camera shake.

Code: [Select]

for i=1, n, 1 do
press("shoot_full_only")
   repeat 
      sleep(50)
   until get_shooting() == true	
   release("shoot_full_only")
   repeat
      sleep(50)
   until get_shooting() == false
end

I keep focus and exposure locked via Canon's default UI, but using af_lock() or nothing at all will re-focus before shooting so I use this instead to keep it locked. Script can still change exposure but camera keeps it locked before shooting.

Code: [Select]

press("shoot_half") 
 repeat
   sleep(50)
until get_shooting() == true

If I add this to the end of the above code like in original HDR script in CHDK wiki, script will wait forever with Canon UI AE lock.

Code: [Select]

repeat
 sleep(50)
until get_shooting() == false

Is there any way to mimic manual shutter button holding via script? It seems to be about as fast as fastest scripts (~ 1.5 fps RAW+JPG) and it is 100% reliable.

Could faster memory card help to go above ~ 1.5 fps or the bottleneck is in hardware? I'm using Sandisk Extreme 30MB/s SDHC UHS-I

I have also tested some motion detect scripts like motion plus and the one in default CHDK, but camera just keeps shooting all the time no matter what threshold I set. Grids will flash either all of them or some of them even if there is nothing happening on the scene. Is this hardware limitation or this camera requires special script for motion detect? I would like to use it for lightning captures mostly.

« Last Edit: 08 / August / 2013, 05:36:13 by Fotoni »

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waterwingz

12140

Re: Fastest continuous shooting + motion detect (IXUS 300 HS)

« Reply #1 on: 29 / July / 2013, 08:40:52 »

Quote from: Fotoni on 29 / July / 2013, 05:16:22

and sometimes it just crash.

What kind of crash? The script aborts or stops running or hangs? Or the camera actually crashes and either hangs or restarts ?

Quote

Is there any way to mimic manual shutter button holding via script? It seems to be about as fast as fastest scripts (~ 1.5 fps RAW+JPG) and it is 100% reliable.

There have been scripts posted that do just that -
http://chdk.setepontos.com/index.php?topic=8602.msg93287#msg93287

Lapser has a couple of threads on the subject.
http://chdk.setepontos.com/index.php?topic=8997
You basically set the camera for shooting in contiuous mode through the Canon UI and the script just pushes the shutter button and holds it down.

Quote

Could faster memory card help to go above ~ 1.5 fps or the bottleneck is in hardware? I'm using Sandisk Extreme 30MB/s SDHC UHS-I

I don't think that will change much - especially if you can actually get that speed while saving a CHDK RAW.

Quote

I have also tested some motion detect scripts like motion plus and the one in default CHDK, but camera just keeps shooting all the time no matter what threshold I set. Grids will flash either all of them or some of them even if there is nothing happening on the scene. Is this hardware limitation or this camera requires special script for motion detect? I would like to use it for lightning captures mostly.

Take a look at this : http://chdk.wikia.com/wiki/Motion_Detection#Performance_Tuning_.28Sensitivity.29
Increasing the delay value "p" should solve your problem.

Update :

Quote

I keep focus and exposure locked via Canon's default UI, but using af_lock() or nothing at all will re-focus before shooting so I use this instead to keep it locked. Script can still change exposure but camera keeps it locked before shooting.

This might be of some interest : http://chdk.setepontos.com/index.php?topic=9533.msg97810#msg97810

« Last Edit: 29 / July / 2013, 09:38:15 by waterwingz »

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Ported : A1200 SD940 G10 Powershot N G16

Fotoni

9

Re: Fastest continuous shooting + motion detect (IXUS 300 HS)

« Reply #2 on: 02 / August / 2013, 15:30:02 »

Camera screen turns all black (backlight still on) and it doesn't respond for several seconds. Then red light start to flash and there is white text which says there is camera error, E26 code and then camera shutdowns. Sometimes fast HDR script works, sometimes it skips one or more RAW files and mostly just crash like I described. Camera is unresponsive for a while even when these fast scripts executed successfully. Screen looks normal but buttons don't do anything. After waiting for while, everything works again.

How much exposure change between shots should slowdown continuous shooting? Because I can only use slow HDR scripts like Ultra HDR Script for reliable exposure bracketing without crashes or random RAW skipping. It takes at least like 2-3 seconds between shots even when slowest shutter speed is something like 1/30

I have tried to set hyperfocal distance from a script, but it tries to focus for short amount of time and then the camera just shutdown with lens out. Adding sleep delays, AFL or set_aflock() does not help. It seems that get_focus() works oddly too because I have tried to get nearest hyperfocal distance with autofocus based on get_focus() numbers to match with get_dofinfo().hyp_dist, but still it does not focus to infinity because far details are blurry in those photos. I don't know how this camera will report get_focus() because the number can vary a lot between short distances. Well, hyperfocal does not matter that much with these small cameras, but still near limit distance might suffer a meter or two, if I do loose estimate and autofocus too far?

« Last Edit: 08 / August / 2013, 05:50:36 by Fotoni »

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