Trying to remember what we did last Monday and Tuesday in the Studio. Pulso and Primo.
Broncolor Pulso 2: A mains powerpack that distributes output evenly (symmetrically) between the number of heads attached. You’ll remember that the output starts at level 6, the lowest, and goes as high as 10 with each whole division altering the output by a factor of two or one ‘stop’. Setting 7 being twice the output of setting 6 and so on. You’ll also remember that you can adjust the output by tenths of ‘stops’ as well. Modelling light settings, Off, Low, Full, P1, P2, P3.
Broncolor Primo: A mains powerpack with the same output as the Pulso 2 which also distributes the output evenly (symmetrically) between the number of heads attached. This unit has a few less features than the Pulso, only 3 head sockets, a 4 stop range (1/1, 1/2, 1/4, 1/8) with 1/3 stop increments only and where 1/1 is the same outpout as 10 on the Pulso. A couple less modelling light settings, Off, Full, P2, P3 only. Check the 100 year old notes I distributed, the diagram show P1 and P2, it took all these years for an observant person to notice this.
Use of the Modelling Light settings.
The modelling light shows us what the flash exposure will look like and ideally if you have two flash units on different output settings the modelling lights should show this difference. Modelling light settings of Low and Full are independent off the flash out, in other words regardless of what you set the flash output to the modelling light will only ever be on Low or Full. This is fine for a unit that distributes flash evenly between the heads, for an asymmetrical unit it would be important to match the modelling light output to the flash output so that you can SEE the difference between the heads. If you manage to get your hands on more than one of the Pulso and Primo powerpacks for a shoot you can set each pack to a different flash output and therefore have more creative control over the lighting. If you do this you need to ensure your modelling lights are set to a Proportional setting, P1, P2 or P3 and it should be the same P setting on each unit. Using the modelling light proportional settings means the modelling light changes along with the flash, in other words the modelling light is in proportion to the flash output, it’s a case of WISIWIG, what you see is what you get. It is very important however that which ever P setting you choose it MUST be the same on each unit, this means P2 or P3 on BOTH.
A reminder that you are going to bring in some portraits to use as inspiration for your shoot this week. You’ll be deconstructing the shots to establish how they were shot, you’ll then reproduce the lighting schemes. You’ll also plan your own shots with.
Quick quiz:
For a given flash to subject distance a Pulso 2 on flash setting 10 and with a P70 reflector dish is measured with an incident meter and the reading is f64.
What is the flash to subject distance? Answer: 1m
What would the indicated f-number be at a 2m flash-to-subject distance? Answer: f32 (inverse square law)
If in a given situation the meter indicates f64 when the Pulso 2 is set to a flash output of 10, what would the indicated f-number be when the flash is set to;
Output 9 Answer: f45
Output 8
Output 7
Output 6 Answer: f16
Output 8 on the Pulso 2 unit is the same as 1/4 on the Primo unit. (2 stops down from maximum)
