KAP & UAV Exposure Control Intervalometer Script - page 44 - Completed and Working Scripts - CHDK Forum

KAP & UAV Exposure Control Intervalometer Script

  • 1068 Replies
  • 343452 Views
Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #430 on: 03 / June / 2015, 14:56:22 »
Advertisements
Here are the two images:

https://www.anony.ws/image/DK6U
https://www.anony.ws/image/DK6p

It also took the corresponding raw image. I should disable the setting for raw files, right? We only want jpg images here?

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #431 on: 03 / June / 2015, 17:52:17 »
Here are the two images:
https://www.anony.ws/image/DK6U
https://www.anony.ws/image/DK6p
Well, two images look to be exposed identically.  Yet the exif info reports two very different exposures :

1/160s ƒ/2.8 ISO200   vs    1/1250s ƒ/2.8 ISO200

The only way that can happen is if CHDK was able to successfully insert the ND filter for the image with the 1/160 s exposure time.

All of which tells me that ND filter control appears to be working correctly on your camera.   And that I need to find another explanation of why the exposure is so dark in the original images you posted.


Quote
It also took the corresponding raw image. I should disable the setting for raw files, right? We only want jpg images here?
For the purposes of the test strip,  RAW images are not needed.  But they don't hurt anything.

For the purposes of your previous test,  having RAW images enabled explains the timeout shooting errors I was seeing.  I've increased the timeout value to compensate for shooting with RAW enabled.
Ported :   A1200    SD940   G10    Powershot N    G16

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #432 on: 04 / June / 2015, 10:04:48 »
All of which tells me that ND filter control appears to be working correctly on your camera.   And that I need to find another explanation of why the exposure is so dark in the original images you posted.
I've now retested the ND filter logic of kap_uav.lua on my trusty A1200 (which like your camera has an ND filter and not an adjustable aperture). 

Everything works as expected when I setup the script parameters so that the camera uses the ND filter when the Canon logic would not have used it,  and it works as expected when I setup the script parameters so that the camera does uses the ND filter when the Canon logic would have used it.

Looking at the log again, and your posted images,  I am completely convinced that the under exposure is a result of the ND filter being engaged in the light path when the script specifically tried to remove it.

With over 3200 downloads and the script in common usage in the KAP and UAV community,  your exact issue has not been reported by anyone else.  There have been changes in the latest script version but nothing that should affect ND filter operation. 

All of which suggests either something in the way the camera is setup,  something unique about the IXUS115, or something is "sticky" in your camera.  But confounding that is the fact that your camera worked properly in the ND filter test.

To test all of this, I've updated the kap_uav.lua v3.6 beta version of the next release of the script to include a delay after the ND filter is moved.  If you could test this it would be interesting to know the results.  I'd rather not make that a permanent change as it slows down the time between reading the exposure and taking the actual shot - bad news on a moving kite or UAV.

tl;dr : On a technical note,  there is a slight difference between the test script and the kap_uav script in the way the shot actually happens.  The test script sets the exposure parameters and then calls the shoot() function.   The kap_uav script sets the exposure parameters inside of the "shoot_half" prior to the "shoot_full_only".  I suppose it's possible that it takes a few milliseconds for the ND filter to move and the kap_uav filter does the "shoot_full_only" before the filter has finished moving.  All depends on the timing through the action stack.
Ported :   A1200    SD940   G10    Powershot N    G16

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #433 on: 04 / June / 2015, 11:31:45 »
Thanks. I was able to take some pictures. Here is one from today: https://www.anony.ws/image/DKTZ


Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #434 on: 04 / June / 2015, 12:42:06 »
Thanks. I was able to take some pictures. Here is one from today: https://www.anony.ws/image/DKTZ
Thanks.

Still about 3 f-stops dark.   Assuming you used the new version of the script,  adding a delay after setting the ND filter did not solve the problem.

One thing I have noticed in your logs is that your camera has both Continuous Autofocus and  Servo Autofocus enabled in the Canon settings.   At a minimum,  this will interfer with the script's ability to lock focus at infinity.  It's also remotely possible that it's affecting the ND filter control too.

I'd suggest putting the the camera into P mode rather than Auto (slider switch on top of camera) to disable Continuous Autofocus.  Then go into the Canon menus and turn off Servo AF. Set AF Frame to Center (not Tracking Autofocus).  You might also want to disable image stabilization (IS-mode).   

See if that makes a difference in the ND filter control?
Ported :   A1200    SD940   G10    Powershot N    G16

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #435 on: 05 / June / 2015, 04:40:26 »
Thanks again! I was able to set the camera to the settings you recommended. Here is a latest image:

https://www.anony.ws/image/DKCA

Looks much better compared to last time but still not perfect. What do you think is going on?

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #436 on: 05 / June / 2015, 10:46:13 »
Looks much better compared to last time but still not perfect. What do you think is going on?
Looks pretty close to perfect to me.  8)

Can you do one more test where you let the script take a couple of photos, halt the script, restart the camera (power off/on) to clear all settings,  and then take a couple of picture in "P" mode shooting normally.  Post the results -  I would be very interested to see how those image compare.

Meanwhile, the reported aperture in the exif says f2.8.   Which might mean the camera was not going to insert the ND filter anyway and so the exposure is better by accident.   Would you please post the most recent log file so I can see what the script was doing?
Ported :   A1200    SD940   G10    Powershot N    G16

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #437 on: 05 / June / 2015, 11:09:57 »
Looking at the latest images, I agree with you. The images look very good! :)

Here are the two images one before and one after shutting off the script and power cycling the camera. The black bar at the bottom of the before image is just the floor under the camera...

https://www.anony.ws/image/DKej
https://www.anony.ws/image/DKe7

I have also attached the KAP.log.

When I pressed menu to stop the script, It showed a "log file open error". Do not know what this means.


Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #438 on: 05 / June / 2015, 16:12:35 »
Here are the two images one before and one after shutting off the script and power cycling the camera. The black bar at the bottom of the before image is just the floor under the camera...
The images look identical but the exif info indicates the f-stops are three apart.

Script  Image : IMG 5451
1/1500s ƒ/8 ISO100

Canon Image : IMG 5454
1/1500s ƒ/2.8 ISO100

I believe that both image are taken with the ND filter out.  The CHDK script image reports f8 is really f2.8.  I'm also suspicious of the Canon image settings - they are too much like the Script settings even though you did a power cycle between the two pictures.

Quote
I have also attached the KAP.log.  When I pressed menu to stop the script, It showed a "log file open error". Do not know what this means.
Unfortunately,  it means the script was unable to open the log file as it existed (camera too busy doing other I/O) and thus did not write out the log data.  When this happens during normal shooting,  the script just carries on and retries later.  On script exit it does not get the chance to retry though - I will have to fix that.

Meanwhile, that means I don't have data from our last posted images.   I'll dig back through the log for the entries correcsponding to some of the earlier images you posted.

Edit :
Thanks again! I was able to set the camera to the settings you recommended. Here is a latest image:
https://www.anony.ws/image/DKCA
I searched the log file and the entry for this image is missing.  Did you shoot it with the script?  (If so, then we had another log file write error on exit ..)
« Last Edit: 05 / June / 2015, 16:25:26 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

Re: KAP & UAV Exposure Control Intervalometer Script
« Reply #439 on: 06 / June / 2015, 09:36:03 »
Hello

Sorry! I made a mistake in my previous test. When I power cycled the camera, I forgot to switch off the KAP script. So the second image is also taken with the script running! This time, I did it right.

Here are the two images (one with script running and then switched off the camera, turned off the script by making the SD card RW and then using the P mode of the camera to take the picture):

https://www.anony.ws/image/D6Dx
https://www.anony.ws/image/D6Dz

The images look pretty identical..

I have also uploaded the log.

 

Related Topics