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8mm film scanner / How many pictures possible per ten seconds?

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Re: Zoom setting and focusing on script
« Reply #20 on: 21 / October / 2015, 20:23:53 »
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That'd be super! Thanks already!
PM'd you a link to a test version with 

Code: [Select]
     #define  CAM_NEED_SET_ZOOM_DELAY          1
     #define  CAM_USE_ALT_PT_MoveOpticalZoomAt 1   
added to the build.

Was unable to use :

Code: [Select]
   #define  CAM_USE_ALT_SET_ZOOM_POINT       1         as the ixus55 is a propset 1 camera and PROPCASE_DIGITAL_ZOOM_MODE not defined for that propset.

Not sure if this will help but it's worth a try.

BTW,   this is a pretty old issue that has never really been solved  :  set_zoom problems in uBASIC & Lua scripts
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Zoom setting and focusing on script
« Reply #21 on: 22 / October / 2015, 00:41:44 »
Wonderful, thank you very much! I will try this as soon as I get home from the business trip.

BTW here's a little video to show you how the film gate works:

https://youtu.be/3EMSqx0t4Kw

As the location of the film is very highly stable, I would love to cut down the imaging time by not focusing for every frame; if I focus, it'll take 4 or more seconds per frame, and with 4,860 frames per 4.5 minutes of film, every second counts. At four seconds per frame, I am looking at 5h20m of scanning time, and with 3 seconds per frame, 4 hours.

The Arduino now runs at 30 rpm, giving me one second of stable frame in place during which to capture it, and another second during which the film is in motion in the gate. I can of course make it 20 rpm for three seconds per film travel/frame capture, or 15 rpm for four.

I plan to use a motion detector script to trigger the shoot, because I would like to avoid having to trigger with the Arduino. That requires a microswitch rigged to the axle between the Arduino and the film gate. The ideal setup would be this:

1) zoom to max
2) focus manually and lock
3) start script, wait for Arduino to move film
4) detect motion at gate, wait 500ms (or whatever is needed to let the film gate settle)
5) shoot before the next trigger happens
6) repeat 4 & 5 until out of film.

If I am wrong with the values here, ie. what is possible and what is not, I'd love to work with you to develop a script that would do what I need.

This forum, by the way, is one o f the friendliest and most professional I have come across - thank you all.
« Last Edit: 22 / October / 2015, 00:43:24 by heikkiH »

Zoom setting and focusing on script
« Reply #22 on: 22 / October / 2015, 04:51:48 »
If we can't fix the issue with using zoom and focus with the ixus55, then maybe it does not matter?

You can set the zoom position manually prior to starting the script. Alternatively, you could use  scripting button presses to move the zoom all the way in and avoid the set_zoom function completely.

This assumes you can find a fixed distance to use with the set_focus function.  Alternatively,  you could do as srsa_4c suggests and simply lock focus (set_aflock), check the result, and either go ahead or redo the focus lock until you like the result.  Using somethign like chdkptp from your PC would let you download and inspect your test images immediately.

Having said that, you should be able to get the shot rate down to about one every two seconds if you lock focus and exposure. Triggering the camera from the Arudino via CHDK USB remote takes only one resistor and half a USB cable. I'll bet that will be easier to work with than motion detection if you really want to go as fast as possible?  The ultimate setup would probably see the Ardunio using a phototransistor to monitor one of the camera's LED or the AF lamp,  which you would then drive from the script to indicate the completion of each exposure.   And why not drive the servo faster while moving the film and only slow it down - or stop it - long enough for your desired exposure time?

Finally,  I don't see it mentioned in this thread so I'll suggest that you ensure you have continuous autofocus, servo autofocus,  and face detection disabled in the Canon menu when you use the posted test script.

edited : more ideas
« Last Edit: 22 / October / 2015, 08:55:19 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Zoom setting and focusing on script
« Reply #23 on: 26 / October / 2015, 02:11:12 »
Hi,

I believe you're right. I'll start looking into the manual focus/zoom instead of programmatic approaches.

As for Arduino triggering mechanically, I'd still try to trigger via motion detection. The reason is that in the film there are both white and black frames, which would not be needed to be captured.

if it gives the slightest trouble, though, I will build in a microswitch to send voltage via the USB. I have already built a remote USB, and it works fine. It takes the voltage from the USB port directly, no battery required. And I have a point in the film gate that should

Thanks all for helping a n00bie!


Hooking an Arduino into the CHDK USB Remote, and file save location
« Reply #24 on: 02 / November / 2015, 11:48:47 »
Hi all,

I am trying to get an Arduino to trigger the camera via the USB.

The schematic in the picture shows a connection which lights up a LED; I imagine I can use the very same connection to send +5V to the USB port for 500 msec. The only thing I am not sure about is this: do I need a pull-down resistor in the ground wire coming from the USB, and if yes, what size?

The switch here will be mechanically pressed by the film gate as it moves horizontally. Ideally it'd then trigger the camera as fast as possible. It's an Ixus 55, so what settings should I use on it? AF lock and zoom lock anyway?

And finally - is it possible to use CHDK to save images directly on the computer? I am running against a file system limitation, as the 55 can only have a 4GB card, but movies have more than 5,500 frames, resulting in at least 6GB. Saving on computer would be ideal.

many thanks once more!

Re: Hooking an Arduino into the CHDK USB Remote, and file save location
« Reply #25 on: 02 / November / 2015, 13:24:41 »

The schematic in the picture shows a connection which lights up a LED; I imagine I can use the very same connection to send +5V to the USB port for 500 msec.
What is the four terminal device shown on the protoboard?  If it's a switch then where is the LED?
 
Quote
The only thing I am not sure about is this: do I need a pull-down resistor in the ground wire coming from the USB, and if yes, what size?
No. 

Quote
The switch here will be mechanically pressed by the film gate as it moves horizontally. Ideally it'd then trigger the camera as fast as possible. It's an Ixus 55, so what settings should I use on it? AF lock and zoom lock anyway?
Can you use AE lock or does the image brightness need to change on the fly?

Quote
And finally - is it possible to use CHDK to save images directly on the computer? I am running against a file system limitation, as the 55 can only have a 4GB card, but movies have more than 5,500 frames, resulting in at least 6GB. Saving on computer would be ideal.
It should be possible to use CHDKPTP to constantly upload images and delete.  But you can't have any other script on the running on the camera.  And getting it to work in harmony with your USB remote circuit will be tricky. 
Ported :   A1200    SD940   G10    Powershot N    G16

Re: Hooking an Arduino into the CHDK USB Remote, and file save location
« Reply #26 on: 02 / November / 2015, 14:54:38 »
The four terminal thingy is the pushbutton element on 123Circuits.io, which is an online Arduino simulator. I plan to use just a microswitch with a lid. I will test it tomorrow, especially if I don't need a resistor.

Image intensity will vary in the movies, so having auto exposure is probably a must, but AF and zoom are not.

The image storage thing can be a nuisance but it's not something to kill the project.

I'll get back when I have the results from the tests - thanks again!

Re: Hooking an Arduino into the CHDK USB Remote, and file save location
« Reply #27 on: 03 / November / 2015, 08:39:27 »
The four terminal thingy is the pushbutton element on 123Circuits.io, which is an online Arduino simulator. I plan to use just a microswitch with a lid. I will test it tomorrow, especially if I don't need a resistor.
I can't tell how you plan to connect the USB port on the camera to the Arduino based on what you have posted so far.  Can you give us a diagram (either CAD or a hand drawn sketch scanned or photographed) ?
Ported :   A1200    SD940   G10    Powershot N    G16


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Re: Hooking an Arduino into the CHDK USB Remote, and file save location
« Reply #28 on: 03 / November / 2015, 20:08:37 »
I can't tell how you plan to connect the USB port on the camera to the Arduino based on what you have posted so far.  Can you give us a diagram (either CAD or a hand drawn sketch scanned or photographed) ?
If the idea is to save images directly to PC, probably it would be better to connect camera to PC and control it using chdkptp.

The function of the arduino is to move the film, and to send command to PC to inform that film is at right position.  The PC receives the signal from Arduino, sends the remote shoot command to camera using chdkptp and saves the images to hard disk.

Re: Hooking an Arduino into the CHDK USB Remote, and file save location
« Reply #29 on: 03 / November / 2015, 20:45:09 »
If the idea is to save images directly to PC, probably it would be better to connect camera to PC and control it using chdkptp.
The function of the arduino is to move the film, and to send command to PC to inform that film is at right position.  The PC receives the signal from Arduino, sends the remote shoot command to camera using chdkptp and saves the images to hard disk.
That's where I was headed too.  Although getting the Arduino to talk to the PC takes a bit of doing.  For my test jigs, I get the microcontroller to simulate a serial port output.  My programming interface card will ship that over USB to the PC as if it was an old fashion serial port.   

Of course if you use a Raspberry Pi running chdkptp then it's easy to get real digital I/O and just skip the Arduino completely.
Ported :   A1200    SD940   G10    Powershot N    G16

 

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