Multi-camera setup project. - page 36 - Creative Uses of CHDK - CHDK Forum

Multi-camera setup project.

  • 462 Replies
  • 123313 Views
*

Offline mphx

  • ***
  • 210
Re: Multi-camera setup project.
« Reply #350 on: 19 / June / 2016, 23:14:57 »
Advertisements


As I mentioned before, having multiple cameras should not affect performance. Testing what rate a single a2500 can sustain would be a good place to start. I'll see if I can come up with a simple script to check this.

That would be an interesting script.

Quote
Is "review" enabled in the canon menu?


I am not following you here..when you say canon menu you mean the menu camera has or some chdk menu ?


The operation of the cameras is straightforward to be honest... connect-sync-getting them to rec mode-setting exposure/iso values-shooting
At the end of the day downloading/deleting files/shutdown.


We haven't messed with any menus of the cameras or chdk menus..except for some power saving setting..you know retract lens off  , display always on and flash off.
Things i dont think will have to do anything with our "little problem" here.




*

Online reyalp

  • ******
  • 12942
Re: Multi-camera setup project.
« Reply #351 on: 20 / June / 2016, 00:12:38 »
Quote
Is "review" enabled in the canon menu?


I am not following you here..when you say canon menu you mean the menu camera has or some chdk menu ?
In the regular canon settings menu, when you press the menu key in shooting mode, there's an option called "review" which keeps the last shot image on screen for some time. It should be "off" for your purposes.
Don't forget what the H stands for.

*

Offline mphx

  • ***
  • 210
Re: Multi-camera setup project.
« Reply #352 on: 20 / June / 2016, 05:24:39 »
Quote
Is "review" enabled in the canon menu?


I am not following you here..when you say canon menu you mean the menu camera has or some chdk menu ?
In the regular canon settings menu, when you press the menu key in shooting mode, there's an option called "review" which keeps the last shot image on screen for some time. It should be "off" for your purposes.


I found that menu in a ixus 160 i have in my house .I set it to off and set the camera to shoot 2 shots in like 1000msecs , even 500msecs....No problems.


As you said , after the first synced shot , next one , is irrelevant of the number of the cameras , since each camera is shooting by itself.I have no argument here , but still i don't understand why A2500s are losing "sync" at the second shot if i lower msecs.Since first shot is synced , second one should be too.


Anyways i have to check A2500s' menu at studio to see what's the setting of "review" ..that would be a pain in the [admin: avoid swearing please] to change the setting to all of them :)

*

Online reyalp

  • ******
  • 12942
Re: Multi-camera setup project.
« Reply #353 on: 20 / June / 2016, 16:27:56 »
Anyways i have to check A2500s' menu at studio to see what's the setting of "review" ..that would be a pain in the [admin: avoid swearing please] to change the setting to all of them :)
You may be able to set this from script using http://chdk.wikia.com/wiki/User:Srsa_4c/UI_properties
Don't forget what the H stands for.


*

Offline mphx

  • ***
  • 210
Re: Multi-camera setup project.
« Reply #354 on: 21 / June / 2016, 17:47:59 »
@reyalp


Update on the situation :


We did a test with four A2500...we disable anything that could interfere while shooting... review image while shooting and/or any power saving setting.


We set the time between the 2 shots around to 1500 msecs (0.8 shots/sec in continuous mode is around 1 shot every 1.25 sec)


First "double shot" was spot on.Both synced..then hell got loosed.Shots were all over the place..it never worked again.


We did the same test with two ixus 160 , same result.First 1-2 "double" shots were accurate as hell.Then they got lost..not as much as A2500 , but u could hear the clicks not "hitting" at the exact same time (i am always referring to "second shots")...ofc every "first" shot was synced .


As we were increasing the msecs...from 1500 to up 5000 , sync of the second shots was getting more and more synced.


Since as you said second shot is being "run" independently and not influenced by  the numbers of the cameras...and since the first shots were always synced...results of the above tests can be considered at least weird :)


I am sensing we are missing some factor that interferes to shooting...

*

Online reyalp

  • ******
  • 12942
Re: Multi-camera setup project.
« Reply #355 on: 21 / June / 2016, 22:17:48 »
We set the time between the 2 shots around to 1500 msecs (0.8 shots/sec in continuous mode is around 1 shot every 1.25 sec)

First "double shot" was spot on.Both synced..then hell got loosed.Shots were all over the place..it never worked again.
This sounds like a bug of some kind, but I really have no idea what could cause it. There really shouldn't be much difference between the first call to mc:shoot() and subsequent calls. Knowing the exact sequence of commands you used might help.
Don't forget what the H stands for.

*

Offline mphx

  • ***
  • 210
Re: Multi-camera setup project.
« Reply #356 on: 21 / June / 2016, 22:34:21 »
@reyalp


After the initial connect


Code: [Select]
     mc=require('multicam')
      mc:connect({list=true})
      mc:start()
      mc:cmd('id')
      return mc:cmdwait('rec')


and sync


Code: [Select]
mc:init_sync()

we just execute


Code: [Select]
mc:shoot{shots=2,interval=5000,synctime=100}

for a double shot


nothing fancy..rest functions are "preshoot" and "shoot_hook_sync" in various combinations for single shots...no problem there.Shots (when are single ones are always synced).


Maybe there is something to do with "synctime"?or the shoot() command itself?


Ixus 160 lost sync in second shot after 2-3 double shots..and i had to raise to around 3000msecs...below that de-syncing was starting.
As i was told since i wasnt present in A2500 testing , cameras there were too messy..clicks were all over the place..ixus 160 were losing sync..but the clicks were close to each other (maybe if they were more than two , would behave like A2500...who knows..we dont have more ixus unfortunately)
The test with A2500 were with 4 cameras.



PS : Whats wrong with "code" button ..when i press it , it goes in reverse ..slash in the first bracketed code..not the second...just saying...

*

Offline mphx

  • ***
  • 210
Re: Multi-camera setup project.
« Reply #357 on: 23 / June / 2016, 03:39:30 »
@reyalp


Another thing i wanted to ask , not related with the issue we are discussing in the last few posts.


Imagine the following scenario.


PC1 - camera rig - chdkptp , PC2-chdkptp


User on PC1 , operates the rig.At the end of the day downloads photos from the camera.So far so good.
Scenario wants this user to NOT be able to manipulate downloaded photos.
Photos are being transferred to PC2 and this user now can do whatever he wants with the photos.


So the question is , can chdkptp implement an encrypt/decrypt function?Encrypt somehow the photos when it copies them to disk and decrypt them with some command in order to be "readable" from windows.
Or some kind of different levels of use of the program with the use of "users"?Login to program with different users with different "privileges"?Or something like that...


Just asking if there is the capability to implement such things ...


Thing is that we are about to set up a new rig for a client , and the deal will be that he will send us the photos of every shoot for "modelling"...for some period of time.
We don't want him to have direct access to photos so he can get into the temptation to send the photos to someone else and not us.He will be in another country so we cant "control" what he will do with the photos if he has access to them.


Thanks in advance...again.
« Last Edit: 23 / June / 2016, 04:40:06 by mphx »


*

Online reyalp

  • ******
  • 12942
Re: Multi-camera setup project.
« Reply #358 on: 23 / June / 2016, 16:48:35 »
So the question is , can chdkptp implement an encrypt/decrypt function?Encrypt somehow the photos when it copies them to disk and decrypt them with some command in order to be "readable" from windows.
This is certainly not something I would spend time implementing. There's enough DRM in the world already, and I have other more fun things I'd prefer to work on ;)

A secure solution would be difficult if not impossible, since they still control the cameras. You might be able to implement something outside of chdkptp that makes it slightly less easy for a person without much knowledge to access the images, but I'm not going to spend time thinking about how one would do that.

One could theoretically modify chdkptp to encrypt the files on download, but please remember that chkdptp is licensed under the GPL, so if you modify it, you must make the source available to anyone you provide your modified program to.

Regarding your problem with burst shooting:
I'm still thinking about it, I just had some stuff come up that doesn't leave me with much time for CHDK. Maybe after the weekend I'll have something to test.

Quote
PS : Whats wrong with "code" button ..when i press it , it goes in reverse ..slash in the first bracketed code..not the second...just saying...
I have the WYSIWYG editor turned off in my profile and just type the code tags manually.
Don't forget what the H stands for.

*

Offline mphx

  • ***
  • 210
Re: Multi-camera setup project.
« Reply #359 on: 23 / June / 2016, 19:55:44 »

A secure solution would be difficult if not impossible, since they still control the cameras.
True , the solution of lets say securing the use of photos wont be entirely bulletproof..because as you said , they will still control the cameras...BUT , what will be left to do?Pull out around 80-100 sd cards and copy the photos?I don't think they will go into such trouble.
I am thinking about downloading photos directly to some cloud directory or ftp server or something...still working on that ...

Quote
One could theoretically modify chdkptp to encrypt the files on download, but please remember that chkdptp is licensed under the GPL, so if you modify it, you must make the source available to anyone you provide your modified program to.


I dont think we have the knowledge to mess around with source , but if we will do , we will respect GPL license..i dont think the client will sit and search the source of chdkptp :)

Quote
Regarding your problem with burst shooting:
I'm still thinking about it, I just had some stuff come up that doesn't leave me with much time for CHDK. Maybe after the weekend I'll have something to test.


Any input on it will be much appreciated and useful.



Another thing that came up.Between the two shots we are issuing , we manually turn on and off a pattern projected from a series of projectors (projectors that are linked together and the last one is connected to a second pc).


I recently found out that someone can issue commands through the serial port of these projectors..either with python scripts or simply by creating plain text files with the desired commands and "copying" these texts over the serial port of the projector.


Question is , can we use some way and issue these commands (with any way i dont really care which one) through chdkptp ?


To get an idea how these commands are look like check pages 65-68 in the following file https://www.dropbox.com/s/m6fruwfiwsbotln/GT760-M-en.pdf?dl=0




Thanks again

 

Related Topics