USB triggering delay variance and strobe sync delay circuits - Hotwire! Hardware Mods, Accessories and Insights - CHDK Forum

USB triggering delay variance and strobe sync delay circuits

  • 5 Replies
  • 7382 Views
*

Offline Anaglyphic

  • ***
  • 129
  • Anaglyphic lives!
Advertisements
Since we cannot know all that there is to be known about anything,
 we ought to know a little about everything.
-- Blaise Pascal

*

Offline Anaglyphic

  • ***
  • 129
  • Anaglyphic lives!
Re: USB triggering delay variance and strobe sync delay circuits
« Reply #1 on: 26 / July / 2009, 12:23:52 »
Since we cannot know all that there is to be known about anything,
 we ought to know a little about everything.
-- Blaise Pascal

Re: USB triggering delay variance and strobe sync delay circuits
« Reply #2 on: 26 / July / 2009, 13:01:10 »
Any thoughts?

If you look in the Files section of the Yahoo SDM Group, you will see a circuit that I built from a 5V DIL relay and a couple of components.
After your remote switch is released, the drop-out for the relay will depend on its coil resistance and the size of the low-leakage tantalum capacitor.
I found it works very well.

HOWEVER, someone has designed a commercial USB-remote switch that includes triggering external flashes, expansion to as many cameras as you wish, synchronised time-lapse and provision for external power for long-duration time-lapse.
The PCB design has been sent away for manufacture.

*

Offline fudgey

  • *****
  • 1705
  • a570is
Re: USB triggering delay variance and strobe sync delay circuits
« Reply #3 on: 27 / July / 2009, 06:00:30 »
Question to the functioning brains: Do you think there's any (worthwhile) chance to improve the shot delay variance with CHDK, either globally or per-camera?

Not sure about the functioning part, but I do have one idea worth either trying or squashing by functioning brains:

Don't trigger your flash from a delayed remote signal. Instead, trigger (with delay) from an optical or clue from the camera (like one of its LEDs or LCD backlight), enabling monitoring for this clue by the USB remote trigger signal to prevent spurious flashes.. even listening to the high frequency sound (coupled to the camera chassis) of the iris opening could be feasible, as long as the camera has one and you set the camera in a way that it has to adjust aperture for each shot.

Maybe even CHDK could help blinking the blue LED for you to sync to... not from regular 10 ms intervals but maybe hacking it in exp_drv_task or somewhere else?

*

Offline Anaglyphic

  • ***
  • 129
  • Anaglyphic lives!
Re: USB triggering delay variance and strobe sync delay circuits
« Reply #4 on: 29 / July / 2009, 10:33:19 »
Since we cannot know all that there is to be known about anything,
 we ought to know a little about everything.
-- Blaise Pascal

Re: USB triggering delay variance and strobe sync delay circuits
« Reply #5 on: 29 / July / 2009, 11:09:35 »
Well, I guess that I have a well-stocked bench but have not programmed microcontrollers.
You do not have a well-stocked bench and have programmed microcontrollers.
The required bits will fit inside a Hama grip with a couple of coin-cell batteries or a small 6V camera battery.

The commercial device is not open source, it is one of a wide range of products that the designer sells.

 

Related Topics


SimplePortal © 2008-2014, SimplePortal