A few rookie questions

[LASTOLITE]

1.LASTOLITE HILITE BACKGROUND Every time I see this in use I see it ALL lit up to start with - is this just the modelling lamp from the flash on?

2. I see various wattages for modelling lamps - some at 100w many at 150w and some at 250w - in a small studio space what is best or doesn't it matter?

3. Fan Cooler V Air cooled lights - is there any overheating issues with heat sink / air cooled as opposed to fan cooled ? and how loud are the fans? computer fan loud or more or less?

4. Some lights have the ability to step the power down to 1/32 of full - in comparison to my SB900 what would that mean - same or a much lower figure on the 900 say 1/64?


feel like a right greenhorn

 

[Garry Edwards]

1. Yes, people tend to leave the modelling lamps on, although there's no need to. Obviously, it's the flash that does the work/
2. The flash heads with low powered modelling lamps are generally cheap flash heads with no cooling fan. The more powerful the modelling lamp, the more accurate the indication of shadow density it gives you.
3. The fans tend to be very quiet, about the same size as computer fans. My view is that fans are essential, but there are people who are happy with flash heads that don't have fans.
4. Your SB900 starts off with a lot less power than nearly all flash heads, so at minimum power it produces much less flash energy than a studio head at minimum power.

 

[Canon Bob]

Just to put some numbers in there for comparison.....

Nikon's SB800 and Canon's 580EXII both have about 64 Joules available at maximum output. How efficient they are at using the power is less easy to quantify but it's safe to assume there are significant losses in the system.
The raw numbers show a Speedlight to be around 40% of the power (stored) expected from a low end monolight.

Bob

 

[HoppyUK]

Just to put some numbers in there for comparison.....

Nikon's SB800 and Canon's 580EXII both have about 64 Joules available at maximum output. How efficient they are at using the power is less easy to quantify but it's safe to assume there are significant losses in the system.
The raw numbers show a Speedlight to be around 40% of the power (stored) expected from a low end monolight.

Bob

Tests I've done on 580EX, SB900 and Nissin Di866 put them all over 100Ws equivalent, with the Nikon nearer 150Ws.

Ws (joules) are a bit of a moveable feast, but I've had a hunch that hot-shoe guns were more powerful than some people make out (mostly studio flash manufacturers ) so I checked a few side by side with several studio heads and indeed they are.

I was surprised at just how much poke they can muster, but "at least 100Ws equivalent" would be a conservative estimate of the best. Main problem is slow recycle when they're flat out, and they don't like being hammered much with accessory power packs.

 

[LASTOLITE]

Thanks for the replies!


Think I got over saturated with info....so many people have differing takes on whats the best way to go!


Thing is what did we do without the net! - trial and error I suppose, we all want to maximise our cash and NOT buy something thats gonna prove to be obsolete.

I am after a decent foundation - I can build on I suppose so initial cjoice is critical.

 

[Garry Edwards]

Tests I've done on 580EX, SB900 and Nissin Di866 put them all over 100Ws equivalent, with the Nikon nearer 150Ws.

Ws (joules) are a bit of a moveable feast, but I've had a hunch that hot-shoe guns were more powerful than some people make out (mostly studio flash manufacturers ) so I checked a few side by side with several studio heads and indeed they are.

I was surprised at just how much poke they can muster, but "at least 100Ws equivalent" would be a conservative estimate of the best. Main problem is slow recycle when they're flat out, and they don't like being hammered much with accessory power packs.

And I'll disagree with you until the cows come home
Some of the better hotshoe flashes have a surprisingly high level of effective power, but their actual power output is pretty low - they rely on highly efficient built in reflectors to maximise the apparent output (at the cost of even lighting) and the also rely on narrow angles to boost the figures - for example, I'm pretty convinced that my SB800 has more real power than the SB900, but the SB900 has a 'longer' zoom setting, which distorts the figures.

What really matters IMO is the quality as well as the quantity of the light. With odd exceptions (think Bowens at one end of the scale and Portaflash at the other) studio flash heads tend to have much 'softer' reflectors than hotshoe flashguns, which makes an enormous difference to the perceived quantity of the light as well as to its quality. Years ago, when people were more interested in quality than quantity, manufacturers like Courtenay and Srobex had white painted reflectors. They were very inefficient in terms of output, but very even and relatively soft.

To the OP - apologies for going off topic a bit. Just think about the quality of the light, not the quantity. That's what matters.

 

[Canon Bob]

Tests I've done on 580EX, SB900 and Nissin Di866 put them all over 100Ws equivalent, with the Nikon nearer 150Ws.

Ws (joules) are a bit of a moveable feast, but I've had a hunch that hot-shoe guns were more powerful than some people make out (mostly studio flash manufacturers ) so I checked a few side by side with several studio heads and indeed they are.
........

Richard,

I assume your references "100Ws equivalent" and "Ws (joules) are a bit of a moveable feast" are implying that Ws/Joules are not a guide to light intensity or Guide number?....perfectly true.
Ws (or Joules) are a measurement of stored energy (Capacitance/2 * Voltage squared) and is finite and tangible. The "equivalent" and "moveable feast" part are based on design and efficiency and result ultimately in the guide number.

Bob

 

[HoppyUK]

And I'll disagree with you until the cows come home
Some of the better hotshoe flashes have a surprisingly high level of effective power, but their actual power output is pretty low - they rely on highly efficient built in reflectors to maximise the apparent output (at the cost of even lighting) and the also rely on narrow angles to boost the figures - for example, I'm pretty convinced that my SB800 has more real power than the SB900, but the SB900 has a 'longer' zoom setting, which distorts the figures.

What really matters IMO is the quality as well as the quantity of the light. With odd exceptions (think Bowens at one end of the scale and Portaflash at the other) studio flash heads tend to have much 'softer' reflectors than hotshoe flashguns, which makes an enormous difference to the perceived quantity of the light as well as to its quality. Years ago, when people were more interested in quality than quantity, manufacturers like Courtenay and Srobex had white painted reflectors. They were very inefficient in terms of output, but very even and relatively soft.

To the OP - apologies for going off topic a bit. Just think about the quality of the light, not the quantity. That's what matters.

Garry, I know. As I think you know

And I think you also know that I did those tests alongside the Lencarta Smartflash, ELitePro 300, Elite Pro600 and Safari Li-on, amongst many others - side by side, using an identical light modifer.

Modifier was a 100cm Lastolite Umbrellabox, that fits via a brolly shaft so it can be fitted to anything. It's a reverse firing white umbrella with softbox front - so all the light is collected, scrambled and reflected out of the front in exactly the same way each time. Zoom heads on the guns were set at 24mm I think, but it actually makes very little difference in that Umbrellabox.

Here are some comparisons. Umbrellabox at 1.0m, ISO100.
ElitePro600, f/22d3
Interfit EXD400, f/16d6
Lastolite F400, f/16d5
ElitePro300, f/16d5
Bron Minicom 300Ws, f/16.3
Bowens GM250R, f/16.1
Nikon SB900, f/11d1
Canon 580EX, f/8d8
Nissin Di866, f/8d7

What you make of that, and what value you put on a Ws is an interesting question. Take the Lastolite as a typical 400Ws and the hot-shoe guns get an inflated figure, against the ElitePro300 it's less, against the ElitePro600 it's a bit more.

But either way something between 100Ws and 150Ws is not far off for the Nikon SB900.

 

[HoppyUK]

Richard,

I assume your references "100Ws equivalent" and "Ws (joules) are a bit of a moveable feast" are implying that Ws/Joules are not a guide to light intensity or Guide number?....perfectly true.
Ws (or Joules) are a measurement of stored energy (Capacitance/2 * Voltage squared) and is finite and tangible. The "equivalent" and "moveable feast" part are based on design and efficiency and result ultimately in the guide number.

Bob

Yes, I recently also checked two Elinchrom Quadra heads, both getting 400Ws from the same capacitor/battery pack. The A-head type with modified tube has much faster flash durations, but the S-head converted it into 0.5 stops more light.

As a rule though, having tested about 30 different flashes of one sort or another over recent months (for the reviews in Advanced Photographer magazine) Ws is not a bad guide. There are a few inflated figures out there, and some that appear a bit understated compared to the majority, but in the main it appears to be a more consistent measure of actual light output than guide numbers for example. And you can pro-rata Ws without getting too confused

 

[Garry Edwards]

Richard, thanks for the detailed reply. I'm not trying to prove myself right or you wrong, but just one question...

Weren't all the studio flash heads fired into the brolly box sans reflectors? If so that will have been an accurate test of the studio flash effective flash energy, but will have dramatically inflated the figures for the hotshoe flashes..

 

[HoppyUK]

Richard, thanks for the detailed reply. I'm not trying to prove myself right or you wrong, but just one question...

Weren't all the studio flash heads fired into the brolly box sans reflectors? If so that will have been an accurate test of the studio flash effective flash energy, but will have dramatically inflated the figures for the hotshoe flashes..

No Garry. In all cases, the studio heads were used with their standard umbrella reflectors (I used a Bowens on the Lencartas). That way you can match the angle of projection of hot-shoe guns vs studio heads, though I also tried the hot-shoe guns at all angles between 14mm and 105mm and it only made 0.2 stops difference even at those two extremes.

You also have to use a reflector as without it some flash tubes protrude a bit and can actually 'see' behind, directly to the diffuser front of the Umbrellabox, and that inflates the readings by a few tenths. All the light must be collected and reflected from the rear.

Another advantage of the Umbrellabox is you can slide the heads along the shaft to get the distances the same. I believe it's as accurate a method of comparison testing different brands and types of flash as it's reasonably possible to get.

 

[JonathanRyan]

As a rule though, having tested about 30 different flashes of one sort or another over recent months (for the reviews in Advanced Photographer magazine) Ws is not a bad guide.

It's probably the best we've got. But my bet is that it's likely to become increasingly unreliable (just like watts did when people started using compact fluorescents and LEDs). For example, preliminary tests seem to show IGBT lights throw out a little less light than you'd expect from their w/s rating. But I bet we also see new designs soon that will blow all this out of the water - instantaneous LEDs maybe.

Basically, using w/s as a measure of light output is (if I have my metaphors correct) like using MPG to describe the speed of the car. It's a decent rule of thumb when all cars are similar but it might suggest that a 30 year old land rover is faster than a Tesla.

 

[paul williams]

1.LASTOLITE HILITE BACKGROUND Every time I see this in use I see it ALL lit up to start with - is this just the modelling lamp from the flash on?

2. I see various wattages for modelling lamps - some at 100w many at 150w and some at 250w - in a small studio space what is best or doesn't it matter?

3. Fan Cooler V Air cooled lights - is there any overheating issues with heat sink / air cooled as opposed to fan cooled ? and how loud are the fans? computer fan loud or more or less?

4. Some lights have the ability to step the power down to 1/32 of full - in comparison to my SB900 what would that mean - same or a much lower figure on the 900 say 1/64?


feel like a right greenhorn

1. Yes, people tend to leave the modelling lamps on, although there's no need to. Obviously, it's the flash that does the work/
2. The flash heads with low powered modelling lamps are generally cheap flash heads with no cooling fan. The more powerful the modelling lamp, the more accurate the indication of shadow density it gives you.
3. The fans tend to be very quiet, about the same size as computer fans. My view is that fans are essential, but there are people who are happy with flash heads that don't have fans.
4. Your SB900 starts off with a lot less power than nearly all flash heads, so at minimum power it produces much less flash energy than a studio head at minimum power.

Point 1. as above.

Point 2. I prefer lower power modelling lights as I have a small studio space and don't want the brightness/heat generated. Although my main heads (200ws) are only fitted with 75w halogens as standard they can be used with up-to 205w lamps. I would say if you intend to use the light out doors however, you need a much brighter modelling lamp.

Point 3. I have some units with fans and some without, and I've never had a moments problem with either - even when being used for long periods. I do find the fan noise distracting, but it seems I have issues with low level noises so always have music on anyway. All I would say on the issue is that a cheap unit with a fan is no substitute for a quality unit without!

Point 4. No idea, don't use hot-shoe flash. My main lights go down to 1/64 (quoted as 5ws) power, others to 1/8 and my oldest ones only have full and half power settings. Even with 'only' 200ws on tap I rarely use them on full power. In a large studio last week, kitted out with Elinchrom Style 1200 & 600 & BRXi 500 heads I just couldn't get any of the lights low enough..."how low can they go" is perhaps more important than max output for me.

Paul

 

[HoppyUK]

Point 1. as above.

Point 2. I prefer lower power modelling lights as I have a small studio space and don't want the brightness/heat generated. Although my main heads (200ws) are only fitted with 75w halogens as standard they can be used with up-to 205w lamps. I would say if you intend to use the light out doors however, you need a much brighter modelling lamp.

<snip>

Paul

Another thing about modelling lamps. If you don't turn them down or off at low power, they warm up the light a lot!

Edit: I need to qualify that statement a bit for the unsuspecting. It only applies if you have the modelling light at full power and the flash at minimum, and even then you might not notice it. But if what you're doing is colour-critical, you might get an extra 1000K extra warming, or something of that order. Easy to fix though, you just need to be aware of it.

 

[LASTOLITE]

Great tips - many thanks -