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CHDK PTP multiple instances

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Re: CHDK PTP multiple instances
« Reply #60 on: 23 / September / 2013, 14:35:16 »
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another fascinating [related to this one someday   ??? ] topic at http://chdk.setepontos.com/index.php?topic=10724.msg105584#msg105584

Might be nice to throw away the usb hub network in my first 'primary school picture' in this topic - but I digress...


Edit: Trust there is no problem cross-posting ?
« Last Edit: 24 / September / 2013, 02:36:39 by andrew.stephens.754365 »

Re: CHDK PTP multiple instances
« Reply #61 on: 27 / September / 2013, 08:01:05 »
I ordered two Arduino MEGA 2560 that will address some optocouplers or relais while being connected to a PC too. this way I can upload/download images, exposure settings and all that, while still using chdkptp.

Hi Karmaschinken,

i'm interested to try and understand why you decided to purchase 2 Arduino's - here's a link to the Arduino serial to parallel page http://arduino.cc/en/Tutorial/ShiftOut  - although i've no arduino experience that looks the way to go.

I'm still looking for a suitable multi-channel [optoisolated] FET 'brick '. The only path for voltage decay through the 'non-linear' camera components is still a big unknown [to me at least].

Re: CHDK PTP multiple instances
« Reply #62 on: 30 / September / 2013, 03:54:41 »
I'm not yet sure if i'm going forward or back in my quest for chdk knowledge - but I do have a lot of chdk related browser tabs open in the attempt to inch ahead and link up some useful 'neural pathways'. I suspect it'll be a looong road.

In these circumstances - might someone, perhaps, be so kind as to comment based on the following, quoted from http://chdk.setepontos.com/index.php?topic=6601.msg70040#msg70040

"...As an aside, it would be neat to give wait_until_remote_button_is_released to the ability to wait for other conditions too. Specifically, to shoot on a particular tick of the tick counter, set earlier by script or code. This would allow shooting via PTP with a repeatable delay "

(i) was this functionality ever developed ? [I guess not]
(ii) if not I assume it would be possible to do so - but, even if it were, would it have any applicability in the case of synchronisation of multiple units ? [I guess not] 

[Query aim -> complete chdkptp solution possible ?] 

As usual, any comment appreciated !

Edit: on second thoughts - I now think my query is ill founded i.e voltage change on the 5V line is required & therefore a chdkptp solution can only ever be a part of the overall solution. A few 'code interpretation' eureka moments needed this end.
« Last Edit: 30 / September / 2013, 06:24:32 by andrew.stephens.754365 »

Re: CHDK PTP multiple instances
« Reply #63 on: 30 / September / 2013, 08:17:09 »
In these circumstances - might someone, perhaps, be so kind as to comment based on the following, quoted from http://chdk.setepontos.com/index.php?topic=6601.msg70040#msg70040
That particular conversation resulted in this thread : http://chdk.setepontos.com/index.php?topic=7127.0

Quote
"...As an aside, it would be neat to give wait_until_remote_button_is_released to the ability to wait for other conditions too. Specifically, to shoot on a particular tick of the tick counter, set earlier by script or code. This would allow shooting via PTP with a repeatable delay "
(i) was this functionality ever developed ? [I guess not]
You guessed correctly.

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(ii) if not I assume it would be possible to do so - but, even if it were, would it have any applicability in the case of synchronisation of multiple units ? [I guess not] 
Correct again.

Quote
Edit: on second thoughts - I now think my query is ill founded i.e voltage change on the 5V line is required & therefore a chdkptp solution can only ever be a part of the overall solution. A few 'code interpretation' eureka moments needed this end.
Basically, you need a signal of some sort that each camera sees and acts on as quickly as possible with as little variation in processing time as possible.
Ported :   A1200    SD940   G10    Powershot N    G16


Re: CHDK PTP multiple instances
« Reply #64 on: 30 / September / 2013, 08:38:15 »
Thanks waterwingz - i'll try and make my next post [a little  :) ] more intelligent.

Edit: the 'USB Remote Switch in CHDK - version 2 implementation thread ' you reference

- i'm sure it'll come as no surprise to learn that's one of the 'chdk related browser tabs' I already have open.

That and reyalp's 'alternative ptp client ' haven't been closed in a couple of weeks now. Also just [bit sad really] found  https://trac.assembla.com/chdk/browser#trunk .

So, by this Christmas [or next   :xmas ] I should have the building blocks to figure what on earth made you consider adding;

'physw_status[USB_IDX] = physw_status[USB_IDX] | USB_MASK ;  // NEW : make it look like 5V is there no matter what'

in the kbd.c file as solution  :blink:

[
step by step, it's only easy when you know how...but it's this sort of thing that really scares me:

http://chdk.setepontos.com/index.php?topic=4290.msg40699#msg40699

"Oh... the gui_kbd_enter() thing. Ok, thanks, I've been looking for that for at least 8 hours :/ "
]
« Last Edit: 30 / September / 2013, 11:51:13 by andrew.stephens.754365 »

Re: CHDK PTP multiple instances
« Reply #65 on: 07 / October / 2013, 18:46:23 »

...referred to by waterwingz here:

http://chdk.setepontos.com/index.php?topic=10687.msg105256#msg105256

"When you have USB remote shooting and remote sync enabled, the shooting sequence "stops" just before the shutter actually opens if the USB power = 5V.   It waits there for the USB power to go to 0v. When that happens, it completes the shot.  It does not care how you got to that point in the shooting sequence (shutter button or USB switch or script) - it just looks at the 5V line and USB setup status."


sensible scenario ? [still haven't read enough  :( ]

assuming the chdkptp 'shoot' command had been issued, as per waterwingz description at reply#41 http://chdk.setepontos.com/index.php?topic=8769.msg105488#msg105488 in this topic, then [before the 5V line is dropped to 0v as described by waterwingz above] can further chdkptp commands be issued [from chdkptp gui or chdkptp script] to adjust 'settings' [being, potentially, focus / exposure / aperture] and these 'adjusted settings' then be the ones used [i.e locked in on multi cams] when the shot is 'completed' [at the time the voltage goes to 0v] - the aim being to setup for future 'studio flash' lighting conditions at capture time.   
« Last Edit: 07 / October / 2013, 18:48:52 by andrew.stephens.754365 »

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Offline reyalp

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Re: CHDK PTP multiple instances
« Reply #66 on: 07 / October / 2013, 23:00:29 »
assuming the chdkptp 'shoot' command had been issued, as per waterwingz description at reply#41 http://chdk.setepontos.com/index.php?topic=8769.msg105488#msg105488 in this topic, then [before the 5V line is dropped to 0v as described by waterwingz above] can further chdkptp commands be issued [from chdkptp gui or chdkptp script] to adjust 'settings' [being, potentially, focus / exposure / aperture] and these 'adjusted settings' then be the ones used [i.e locked in on multi cams] when the shot is 'completed' [at the time the voltage goes to 0v] - the aim being to setup for future 'studio flash' lighting conditions at capture time.
I'm not sure I completely follow the question, but the setting should be set before the shot starts. You  cannot adjust them once the code reaches the remote hook, it sits in a very tight loop to get the minimum latency (and it would almost certainly be too late in the canon shooting process to adjust them anyway.)

If you are in a studio, you should have enough control of the lighting that the time between setting the settings and the capture being made is not critical.
Don't forget what the H stands for.

Re: CHDK PTP multiple instances
« Reply #67 on: 08 / October / 2013, 03:34:21 »
I'm not sure I completely follow the question

I can understand that [since i'm not sure I fully understood the query as I was writing it, but decided to post anyway]  :o

The basis of my thought process was that http://chdk.setepontos.com/index.php?topic=7127.msg79550#msg79550 led me to read http://chdk.wikia.com/wiki/User:Waterwingz/USB_Remote_V2 which states:

"Multi-Camera Synchronization...Enable Sync...This allows CHDK on several cameras to focus, adjust exposure, setup the flash and then wait for a shared signal to complete the shot"

So, according to this, in a studio, at the point in time that the chdkptp 'shoot' command is issued, lighting conditions = ambient. Focus / exposure / [aperture? do P&S have aperture control] are automatically set based on these 'ambient' conditions [is that assumption correct ?].

However, if fast action capture is required based on subsequent tens of microsecond studio-flash capture then ambient light auto generated exposure / focus / aperture settings may be [will be ?] sub-optimal.

but the setting should be set before the shot starts

If these settings can be, programatically, set & 'locked in', based on the expectation of future studio flash conditions [via chdkptp commands/script prior to chdkptp 'shoot'] so that the 'ambient light' "Multi-Camera Synchronization...Enable Sync...This allows CHDK on several cameras to focus, adjust exposure, setup the flash and then wait for a shared signal to complete the shot" settings [somehow  :blink:] have no impact on the 'locked-in expected flash-condition' settings then [I think] that's what i'd like [but my assumption is that this is not possible].

Fantasy land ? Hope this makes some more sense ?
« Last Edit: 08 / October / 2013, 06:37:54 by andrew.stephens.754365 »


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Re: CHDK PTP multiple instances
« Reply #68 on: 08 / October / 2013, 16:14:22 »
So, according to this, in a studio, at the point in time that the chdkptp 'shoot' command is issued, lighting conditions = ambient. Focus / exposure / [aperture? do P&S have aperture control]
Some have adjustable aperture, some don't. Most of the ixus and recent A series do not.
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are automatically set based on these 'ambient' conditions [is that assumption correct ?].
This depends on the canon shooting mode, and whether you have override and settings using CHDK.

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However, if fast action capture is required based on subsequent tens of microsecond studio-flash capture then ambient light auto generated exposure / focus / aperture settings may be [will be ?] sub-optimal.
No consumer camera can adjust the exposure while the flash is in progress. :blink: When the camera uses it's own flash, it knows something about the brightness, distance of the subject and makes a guess. This is often not very good...

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If these settings can be, programatically, set & 'locked in', based on the expectation of future studio flash conditions [via chdkptp commands/script prior to chdkptp 'shoot'] so that the 'ambient light' "Multi-Camera Synchronization...Enable Sync...This allows CHDK on several cameras to focus, adjust exposure, setup the flash and then wait for a shared signal to complete the shot" settings [somehow  :blink:] have no impact on the 'locked-in expected flash-condition' settings then [I think] that's what i'd like [but my assumption is that this is not possible].
I'm still not totally clear what you expect to happen, but
1) using CHDK you can set shutter, ISO, focus (on most cameras) and aperture (if present) to any valid value.
2) You should be able to determine the setting needed to get correct exposure with your flash setup.

It sounds like you may be misunderstanding the remote page. The remote code doesn't have anything to do with setting correct exposure or focus. The part you quoted just means that the remote code allows the camera to wait after those things have been set. It does not set them, you have to arrange that yourself using manual mode, camera auto exposure, or some script or override.
Don't forget what the H stands for.

Re: CHDK PTP multiple instances
« Reply #69 on: 08 / October / 2013, 17:22:28 »
It sounds like you may be misunderstanding the remote page.

Correct - my assumption in:

"Multi-Camera Synchronization...Enable Sync...This allows CHDK on several cameras to focus, adjust exposure, setup the flash and then wait for a shared signal to complete the shot"

was that allows equated to 'focus / exposure adjustment' automatically happening as part of that process. 

The part you quoted just means that the remote code allows the camera to wait after those things have been set. It does not set them, you have to arrange that yourself using manual mode, camera auto exposure, or some script or override.

Good.

fyi, this link describes what i'm trying to do http://www.dreamingrobots.com/forums/viewtopic.php?f=8&t=44&start=10

I must soon buy a camera and start tinkering - but your current wifi investigations introduce a further interesting quandary into that decision  8) 

As usual, appreciate your patience [in contemplating the mind of those who don't understand this].


 

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