O.K. Thanks for image, but I know how capacitor is charged, and how flash tube works. I dont know how to reduce/limit capacitor discharge into lamp to produce lower power of flash (1/2,1/4, 1/8...).Hello,
The ciruit only works when the capacitor is charged with a high voltage.
There are circuits that will charge the capacitor from a battery.
See the attached PDF for more info.
Bertus
Which brings us to:O
O.K. Thanks for image, but I know how capacitor is charged, and how flash tube works. I dont know how to reduce/limit capacitor discharge into lamp to produce lower power of flash (1/2,1/4, 1/8...).
The above quote was taken from here.Before a flash fires, it determines how long it should fire to get the necessary exposure. The longer the flash fires, the brighter it will illuminate the subject. Flash Exposure Compensation works a lot like exposure compensation: turn it down one stop and the flash effectively gets darker; turn it up one stop and it gets brighter.
I was assuming something like that.Commercial flashes control the power level by placing a switch (usually an IGBT) in series with the flash tube.
The flash power is controlled by timing the switch, cutting it off mid discharge for 50%, for example.
Which brings us to:
The above quote was taken from here.
So it becomes a matter of controlling the actual flash duration.I could have a bank of for example four capacitors and choose one of four to control my flash duration. Just as an example Full Power = 8,000 uF, 75% Power = 4,000 uF, 50% Power = 2,000 uF and 25% or 1/4 Power = 1,000 uF. I can mechanically switch or I can electronically select .
View attachment 127257
I can electronically or manually choose the capacitor I want and control the actual flash on time.
OK, that is one idea I have been considering, but I am more interested in circuit with only one big capacitor. I found on net information that is done by thyristor and series of resistor, but so far I couldnt find a funcional circuit.
Ron
Which brings us to:
The above quote was taken from here.
So it becomes a matter of controlling the actual flash duration.I could have a bank of for example four capacitors and choose one of four to control my flash duration. Just as an example Full Power = 8,000 uF, 75% Power = 4,000 uF, 50% Power = 2,000 uF and 25% or 1/4 Power = 1,000 uF. I can mechanically switch or I can electronically select .
View attachment 127257
I can electronically or manually choose the capacitor I want and control the actual flash on time.
Ron
Commercial flashes control the power level by placing a switch (usually an IGBT) in series with the flash tube.
The flash power is controlled by timing the switch, cutting it off mid discharge for 50%, for example.
Which brings us to:
The above quote was taken from here.
So it becomes a matter of controlling the actual flash duration.I could have a bank of for example four capacitors and choose one of four to control my flash duration. Just as an example Full Power = 8,000 uF, 75% Power = 4,000 uF, 50% Power = 2,000 uF and 25% or 1/4 Power = 1,000 uF. I can mechanically switch or I can electronically select .
View attachment 127257
I can electronically or manually choose the capacitor I want and control the actual flash on time.
Ron
OK, that is one idea I have been considering, but I am more interested in circuit with only one big capacitor. I found on net information that is done by thyristor and series of resistor, but so far I couldnt find a funcional circuit.Which brings us to:
The above quote was taken from here.
So it becomes a matter of controlling the actual flash duration.I could have a bank of for example four capacitors and choose one of four to control my flash duration. Just as an example Full Power = 8,000 uF, 75% Power = 4,000 uF, 50% Power = 2,000 uF and 25% or 1/4 Power = 1,000 uF. I can mechanically switch or I can electronically select .
View attachment 127257
I can electronically or manually choose the capacitor I want and control the actual flash on time.
Ron
Post some of its here. More useful informations, more chances to find solution for this.Using Google I can find block type diagrams but I am also having a problem finding an actual circuit. Anyone have anything?
Ron
I found this circuit on some russian site. It is circuit board marked EPT260-01B.Using Google I can find block type diagrams but I am also having a problem finding an actual circuit. Anyone have anything?
Ron