The new Bowens gemini pro 1000 watt and 1500w..
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There are several Bowens users here. I will have mines in a few days too, 500's so can't help with your query.
Gary.
Gary.
Richard King
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What are you shooting?
Pop quiz question.. What's the difference in f-stops between 300W, 600W and 1200W?
HoppyUK
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It's watt-seconds or joules, not watts, and is a measure of electrical power, not light. It also depends on capacitor efficiency and system efficiency
Different brands vary, much less than they used to these days, but there's still a bit of artistic marketing with some. A bit like guide numbers.Edit: I've never actually compared identical systems side by side with that kind of power variable. But it would be interesting to see if the light from a 1200ws head, fed by a power pack and HT lead with its inevitable losses, was indeed two stops brighter than a 300ws monolight of the same brand.
Garry Edwards
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Just 2 stops, or in other words increasing ISO from 100 to 200 effectively produces the same amount of light as spending a lot more money and buying a 600j head instead of a 300j, and changing it to 400 effectively produces the same amount of light a 1200j head.
This is something that people need to think about, because modern digital cameras don't have to be used at very low ISO settings to produce good image quality.
Good point and good question. There are a couple of U.S. companies who use the marketing hype 'effective watt seconds' to indicate that their low powered mono heads produce as much power as much bigger generator units.
I can test that claim, I'm pretty sure of the answer but will do the test and report back.
blinkerz
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putting the iso up decreases the dynamic range of the camera... higher ws means you can use get to use soft modifiers, could be the difference between using difusion panel or not, also means you dont need the light source to be so tight into the frame.. if you want to really control lighting with grids, they soon eat up stops of light.
Garry Edwards
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True, but not by very much.
Also true, but
1. That applies equally whether the flash energy is greater (higher j rating) or whether the ISO is adjusted to increase the effective flash energy
2. I'm constantly banging my head against the wall, trying to encourage people to use creative light shaping tools - but the fact remains that the vast majority of amateur photographers (plus a lot of pros) don't use them and seem to think that 'good' lighting is a couple of umbrellas or softboxes
- for these photographers, high power is pretty well irrelevant.I'm NOT saying that high power really is irrelevant and that nobody should spend money on powerful flash heads, all that I AM saying is that, for most people using modern digital cameras, it is nowhere near as important as it was just a couple of years ago. Sales figures of studio lighting equipment reflects this, with the vast majority of people buying, and perfectly happy with, 200 or 300j flash heads.
Garry Edwards
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Right, I've done the test using the following, both of which are about 10 years old, in perfect working order and which belong to the high quality era.
Elinchrom Style 1200 mono flash head
Elinchrom Chic 2 Generator pack. This is a 2400j generator with symetrical output, so I connected a head to each outlet and deadheaded one of them, so that 1200j was output to the 'live' one. in each case, the same umbrella reflector was fitted to the head and the head to measurement distance was identical.
Measured with my Minolta V flash meter. 10 pops with each head and results averaged.
The result, which happened to be at a distance of 6m, was as follows:
1200 mono head = f/8 decimal 8
Generator pack = f/8 decimal 7.5
Actually the reading from the generator flash varied between decimal 7 and decimal 8, so is probably decimal 7.5, which means that the actual power loss through that 5m cable is no more than 1 1/10th stop and possible only 1/20th stop, which on this equipment at least, means that the claims made for 'effective watt seconds' are nonsense.
HoppyUK
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True, but not by very much.
Also true, but
1. That applies equally whether the flash energy is greater (higher j rating) or whether the ISO is adjusted to increase the effective flash energy
2. I'm constantly banging my head against the wall, trying to encourage people to use creative light shaping tools - but the fact remains that the vast majority of amateur photographers (plus a lot of pros) don't use them and seem to think that 'good' lighting is a couple of umbrellas or softboxes
I'm NOT saying that high power really is irrelevant and that nobody should spend money on powerful flash heads, all that I AM saying is that, for most people using modern digital cameras, it is nowhere near as important as it was just a couple of years ago. Sales figures of studio lighting equipment reflects this, with the vast majority of people buying, and perfectly happy with, 200 or 300j flash heads.
Good comments from Garry.
I would add that the power you need depends entirely on how you use studio lights. Some extreme examples.
I was shooting portraits the other day with a 70cm double-diffuser Rotalux softbox and my D-Lite 200ws heads. The main light, used close-ish, was giving me f/5.6 at ISO100 on minimum power. I have only once used it on full power and that was bouncing it off a high ceiling to fill an entire large Victorian style room.
For regular home portraiture, I would even go so far as to advise against getting high power units as the more likely problem, especially if you want shallow depth of field which is a popular portrait style, is that you won't be able to turn them down low enough.
Years ago I used to shoot studio still life with a 10x8in camera needing f/numbers around f/64 or even f/90 for sufficient depth of field. With ISO50 film, even a 5000ws Strobe console sometimes needed multiple flashes to achieve that. Clearly, those old capacitors were dreadfully inefficient and a lot of juice was lost in the long cables that fed inefficient reflector with Perspex diffusers ('fish fryers' as they were known , basically softboxes, that also weighed a ton).
Back to today, if you need to fight bright daylight with flash, my own simple experiments suggest that working outside on a bright day you don't stand a hope with anything less than 400ws used at close range. You will be constantly on the limit and it's no use using higher ISO or lower f/numbers in that situation - the only way is to make the flash brighter than the ambient and for that I think you should be looking at 1200ws as a realistic minimum. It helps enormously when the weather is dull!
Final comment though, if you want low light and can't turn the light down far enough, a simple neutral density filter will fix that. But when you really need lots of light, to fill big areas or very high f/numbers, there is no subsitute for sheer power and lots of it. Multiple flashing on bulb just isn't practical most of the time.
david1701
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It's watt-seconds or joules, not watts, and is a measure of electrical power, not light. It also depends on capacitor efficiency and system efficiency
Edit: I've never actually compared identical systems side by side with that kind of power variable. But it would be interesting to see if the light from a 1200ws head, fed by a power pack and HT lead with its inevitable losses, was indeed two stops brighter than a 300ws monolight of the same brand.
if ya wanna be pedantic Ws is energy not power
Richard King
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I do know that, I was purposefully using exactly the same terminology as the OP...It's watt-seconds or joules, not watts, and is a measure of electrical power, not light. It also depends on capacitor efficiency and system efficiency
Edit: I've never actually compared identical systems side by side with that kind of power variable. But it would be interesting to see if the light from a 1200ws head, fed by a power pack and HT lead with its inevitable losses, was indeed two stops brighter than a 300ws monolight of the same brand.
Sometimes when we say double, we actually are not quite accurate. When we say improved by 2 or 4 stops that's not quite accurate either, as you need to, as f-stops and ISO are essentially logarithmic, and shutter speed isn't. (you need to sort the logs out in the math, rather than just multiplying or dividing)
The point I am making is that the terminology used by the manufacturers sometimes is a bit misleading. Photography is full of scales that appear linear and are in fact logarithmic etc etc.