motleypixel
New Member
Hello everyone,
I've lurked here the past two days, so I've read a bit and feel I needed to register to get some dialog going on this project.
Quickly first (since this may be a long post).
Goal: Electronically open a 7VDC power leg (essentially an electronic switch) when a green LED is energized. The LED is from an independent system. The pwr supply that needs interrupted during the period of voltage drop across the LED is a separate system.
First post, looking forward to leveraging this community. Background: In a nutshell, I have a business degree, but was 6 years US Navy Submarines (reactor operator). I know fundamentals with regards to electricity and some solid state stuff, but really zero experience in design.
I have a one-off requirement and was wondering if this community could help.
First of all, the system: I have built a DIY Time-Lapse Photography Turn Table: **broken link removed**
I'm controlling the camera with a smart device called a Little Bramper: **broken link removed** Essentially this device can bulb-ramp the shutter.
I'm panning the camera with a worm-gearbox that has a 30:1 gear ratio, powered by a 7.4VDC 2-cell lipo battery, speed controlled by a simple PWM controller. The controller is variable from 0-100% modulation and will recall last setting upon pwr interupt.
Problem: As the turn table rotates very slowly (1 rev. per hour) and the camera begins taking pictures (starting out as a shutter open duration of 40ms or 1/40th sec and ~ 3 second delay before the next shot and then after time goes on the shutter open duration increases to the tune of 2+ seconds). I have found that shutter speeds slower than 2 seconds, with the moving turn table, produces motion blur that is too excessive.
Best solution: Stop the power to the speed controller which will stop the power to the DC 1rpm motor, which will stop rotation of the camera.
How to implement the solution?: The good news is that the Little Bramper has a Green LED that energizes for the exact duration of the shutter open cycle, so if the shutter is at 1/40th second, then the illumination period of the LED is 1/40th second, same with a 2 second shutter speed, etc.
I would like to find a way to harness this LED signal (either light from the LED or Vd across the LED) to electronically open the pwr CKT to the motor speed controller.
Any ideas here?
**broken link removed**
Thanks!
I've lurked here the past two days, so I've read a bit and feel I needed to register to get some dialog going on this project.
Quickly first (since this may be a long post).
Goal: Electronically open a 7VDC power leg (essentially an electronic switch) when a green LED is energized. The LED is from an independent system. The pwr supply that needs interrupted during the period of voltage drop across the LED is a separate system.
First post, looking forward to leveraging this community. Background: In a nutshell, I have a business degree, but was 6 years US Navy Submarines (reactor operator). I know fundamentals with regards to electricity and some solid state stuff, but really zero experience in design.
I have a one-off requirement and was wondering if this community could help.
First of all, the system: I have built a DIY Time-Lapse Photography Turn Table: **broken link removed**
I'm controlling the camera with a smart device called a Little Bramper: **broken link removed** Essentially this device can bulb-ramp the shutter.
I'm panning the camera with a worm-gearbox that has a 30:1 gear ratio, powered by a 7.4VDC 2-cell lipo battery, speed controlled by a simple PWM controller. The controller is variable from 0-100% modulation and will recall last setting upon pwr interupt.
Problem: As the turn table rotates very slowly (1 rev. per hour) and the camera begins taking pictures (starting out as a shutter open duration of 40ms or 1/40th sec and ~ 3 second delay before the next shot and then after time goes on the shutter open duration increases to the tune of 2+ seconds). I have found that shutter speeds slower than 2 seconds, with the moving turn table, produces motion blur that is too excessive.
Best solution: Stop the power to the speed controller which will stop the power to the DC 1rpm motor, which will stop rotation of the camera.
How to implement the solution?: The good news is that the Little Bramper has a Green LED that energizes for the exact duration of the shutter open cycle, so if the shutter is at 1/40th second, then the illumination period of the LED is 1/40th second, same with a 2 second shutter speed, etc.
I would like to find a way to harness this LED signal (either light from the LED or Vd across the LED) to electronically open the pwr CKT to the motor speed controller.
Any ideas here?
**broken link removed**
Thanks!