Do you use flash?

Good read for many flash users, could perhaps be seen as a bit basic for some but very well explained.

What is 'pwn' ?
 
Good read for many flash users, could perhaps be seen as a bit basic for some but very well explained.

What is 'pwn' ?

Basic for some but for most (including me) it's a confusing and difficult law to fathom.

I've had problems with mathematics as long as I can remember so I appreciate varying explanations and methods of teaching.

The meaning of Pwn.
 
As i said it is a good explanation, but really just double the distance/quarter the power, or half the distance/quaduple the power.
is all you need to know.

One point though, this works for any type of electromagnetic radiation from a point source in free space, any electromagnetic wave, of which light is just a fraction. (sound, UV IR, X-rays and Gamma rays) will conform too.

The bit about free space is important as you will get varying results in enclosed spaces due to reflection or absorbtion, and the inverse square law ceases to work.

LOL, just read the Wiki on pwn, I assumed that it was just a typo, so you can learn something new everyday.
 
Thank you for the link Tomas, Will read it later with a glass of JD and coke. :)
 
As i said it is a good explanation, but really just double the distance/quarter the power, or half the distance/quaduple the power.
is all you need to know.

One point though, this works for any type of electromagnetic radiation from a point source in free space, any electromagnetic wave, of which light is just a fraction. (sound, UV IR, X-rays and Gamma rays) will conform too.

The bit about free space is important as you will get varying results in enclosed spaces due to reflection or absorbtion, and the inverse square law ceases to work.

Now y'see Ed, there you go with all that science, physics and logic stuff that transforms us mere mortals into dribbling cabbages. :lol:

Looks like you should write an article on it too mate, the more views the better as far as I'm concerned! Yours sounds cool too! ;)

LOL, just read the Wiki on pwn, I assumed that it was just a typo, so you can learn something new everyday.

Aye, tis true :lol:


Thank you for the link Tomas, Will read it later with a glass of JD and coke. :)

Ney bother mate, maybe jettison the JD though :lol:
 
It isn't so much basic - nothing wrong with that - as simplistic, because although it does mention that the ISL applies to point sources of energy it doesn't define a point source, so people might assume that flashguns are studio lights are point sources when in fact they aren't.

OK, a hotshoe flash is pretty small and at distances of a few feet they do come close to being point sources - but what about, say, a 4' wide softbox at a distance of 1' from the subject?
Answer: Millions of separate point sources, some of which travel 1' to the subject, some of which travel very much further, completely bu****** up the ISL calculations.
And then of course we have the free space factor, as mentioned by Ed Bray. How often do we photograph in free space?

No, the ISL is an immutable law of practical physics that can only be applied in theoretical terms. Its practical functions is that it just helps to explain why flash loses power over distance. It doesn't work in practical, linear terms with anything other than a hotshoe flash used on a distant subject photgraphed from the top of Everest.
 
It isn't so much basic - nothing wrong with that - as simplistic, because although it does mention that the ISL applies to point sources of energy it doesn't define a point source, so people might assume that flashguns are studio lights are point sources when in fact they aren't.

This wouldn't be another biased and disproportionate dig at hot shoe flashes would it Garry? :nono:
 
This wouldn't be another biased and disproportionate dig at hot shoe flashes would it Garry? :nono:
No - and I don't think I'm biased against hotshoe flashes anyway - I'm very happy with my SB-800s, use them whenever a hotshoe flash helps.
I just recognize the need for the right horse for the right course, and prefer to use studio flash when studio flash does the job better - i.e. in the studio, where it's better IMO to use flashes that allow the use of effective light shaping tools.

I mentioned hotshoe flashes only because they're small, and the nearest thing you can get to a point source of energy.
 
No - and I don't think I'm biased against hotshoe flashes anyway - I'm very happy with my SB-800s, use them whenever a hotshoe flash helps.

I just recognize the need for the right horse for the right course, and prefer to use studio flash when studio flash does the job better - i.e. in the studio, where it's better IMO to use flashes that allow the use of effective light shaping tools.

With all due respect Garry, I'm not convinced that your feelings on the subject are balanced, I still feel that as you have access to gear the rest of us mortals don't have so freely, you don't consider the capabilities very fairly.

If you have a closer look at Dustin's work, studio flashes would make his project close to impossible, especially considering his commitments and daily routine aside of the project itself.

http://photography.dustindiaz.com/

Have a look at this picture:

http://bighugelabs.com/flickr/onblack.php?id=3431126596&size=large

Our tastes my differ but I'm sure you can appreciate that it's one damn fine piece of photography?
Using a higher output flash would not offer any advantage.

You mention that you consider the use of a hotshoe when it 'helps' but would you consider the benefits of lighting an entire shot with them?
My apologies but I have my doubts.

I mentioned hotshoe flashes only because they're small, and the nearest thing you can get to a point source of energy.

But they are not any less of light source just because of their output, forgive my ignorance but it's almost as if you were implying that the inverse square law doesn't apply to hot shoe flashes or anything else 'small' :shrug:

Man flash makes my head hurt! :shake:

It's just light mate :D, shaping it and applying it to enhance or accent a scene in a way that assists your creative vision and imagination.

I think this is initially where many folk (including myself) seem to get a little distracted, or confused.
It's simply light all in all, whether it's a 60 watt second hot shoe flash, a 1600 watt second profoto flash head or a gazillion watt motion picture fresnel or flood.

It's all light and the fundamental principles remain the same.
 
It's just light mate :D, shaping it and applying it to enhance or accent a scene in a way that assists your creative vision and imagination.

I think this is initially where many folk (including myself) seem to get a little distracted, or confused.
It's simply light all in all, whether it's a 60 watt second hot shoe flash, a 1600 watt second profoto flash head or a gazillion watt motion picture fresnel or flood.

It's all light and the fundamental principles remain the same.

Oh yeah, know that. Getting the damn flash to actually look natural though is melting my brain and keeping Duracell in business! Full power, half power, ETTL, manual, exposure comp., remote trigger, yadda yadda yadda :nuts:

Won't let it beat me though. I will get there. I will get there. I will get there......
 
Won't let it beat me though. I will get there. I will get there. I will get there......

That's the spirit!

Little by little, bit by bit. IMO, I'd start with the most simplified set up possible, especially if your feeling 'hurt' by the whole shindig.

I was the opposite, I went in tooth, hammer and nail and got a little lost, then I went back to basics and got a much better idea of how to go about adding my own or creating my own lighting.

Still fall off the wagon from time to time but there's always things to be learnt from cuts and bruises ;)
 
Pretty much what I've been doing to be honest.

Was out in the garden again today just shooting stuff at random and trying to work out what's what with the flash. Don't think I learnt a great deal to be honest, but if I don't try it I won't learn anything, so it's worth a go.

The whole 'bung it on ETTL and use AV and let the camera work out the rest' wasn't quite giving me what I expected, so next practice will be trying something different.

As I've always said, everyone falls down, it's how you get back up that matters :D
 
forgive my ignorance but it's almost as if you were implying that the inverse square law doesn't apply to hot shoe flashes or anything else 'small' :shrug:

No, other way round. What I'm saying is that the Inverse Square Law doesn't apply to ANY kind or photographic lighting (in linear terms) because we don't often use point sources of light in free space. But the Inverse Square Law applies much more directly to a hotshoe flash, used on the top of Mount Everest, than to any other type of lighting or any other type of environment.

As for your other points, interesting and well worth a reply - so I'm starting a new thread, to avoid hijacking this one.
 
I find that the ISL is like maths at school - I think I have it all sussed out, until the numbers and calculations are introduced and then I can feel my eyeslids getting heavy and then as I start to re.......zzzzzzzzzzzzzzzzzzzzzzz :lol:
 
...Getting the damn flash to actually look natural though is melting my brain and keeping Duracell in business! Full power, half power, ETTL, manual, exposure comp., remote trigger, yadda yadda yadda.....
I use flash for about 70 per cent of my magazine work and even though i've been doing it for years, i still have moments when I get brain fade and everything I know (or think I know) dissapears and I'm left feeling like a noob again.

I think the whole (i)TTL business is great but A) gives a false reassurance to the user that the results will be perfect, and B) doesn't always promote experimentation and to a similar degree, learning about getting more from your flash. My SB800 is as reliable as they come compared to my old TTL Mtez hammerhead but it's by no means perfect – I still shout at it at times!! :)

I actually prefer working in manual all the time these days, whether its with one flash or three. It's like lighting a studio using manual power setting on flasheads, albeit with changing ambient light. The size of the flash and the output power is just one of those things – I don't fret about it.

I did a shoot this morning where I had to shoot a guy fishing 10ft away on a 12-24mm lens, with suns just out of frame and a fish being netted a few feet from the lens - using iTTL was pants. The flash didn't know that I just wanted flash directed at he guy t get rifd of his shadows and ceretainly didn't realise that it needed to pump itself up to full power - only manual allowed me to do that.

I've only recently gottern into flash in a big way after seeing folks on here doing off-camera flash - before it was one flash, one hotshoe – and I have to admit the tech speak (strobism, off-camera, sync cords...) was mightily off putting, I got round that by just ignoring the tech speak, thinking in logical terms (almost like a studio photographer)and dealing with lighting the scene in steps. And that's where manual is my best friend. :)

DSC4786.jpg
 
I thought it was a good read and well explained.
Zack Arias does a good job of explaining it on his DVD too :)
 
One point though, this works for any type of electromagnetic radiation from a point source in free space, any electromagnetic wave, of which light is just a fraction. (sound, UV IR, X-rays and Gamma rays) will conform too.

Just to be a pedant (my wife will tell you I always am!), sound isn't an electromagnetic wave.

Spot on with everything else though!
 
I'm with Garry & I love my speedlights too - so no bias there

You only have to use a flashmetre with any form of flash to soon realise the ISL is pants in the real world when discussing lighting (other than the top of Everest of course ;))

DD
 
Simmotino, don't fret - whatever shooting mode you're in manual flash is easy. It's hard to explain in words at times (it's deffo more of a hands-on thing).

I don't know what you're shooting but if you're like me and have a bit of thinking time, it's easy:

As you can see I do angling stuff so do have time contraints when the action happens but plenty of 'downtime' and second chances as the guys are fishing. Depending on what I want I'll set the shooting mode (P, AV etc). I tend to underexpose a little - my D200 needs 1/3rd dialing in anyway for accurate exposure so i usually shoot 2/3rds - 1 stop under; this is my base exposure. Then I just have a test shot with the flash at what I reckon will be fine power-wise and work from there. Once the histogram and review screen tell you it's fine you're done - it's no slower than shooting in auto/TTL.

The good thing about my SB800 is you press up to increase power and down to reduce it, easy, no other fiddling bar deciding on whether a diffuser is needed for close-up work. Think this is the case with most modern flashguns. I actually find myself playing around more with flash settings when shooting in full auto (on the flash and the camera) - the camera just can't be relied on 100% to give accurate flash exposure.

The only time that manual is that little bit trickier is when you're faced with tricky, changing light, you know, when clouds move fast and change light conditions. Still, I just rely ont he camera to meter the ambient and I key in the flash - easy. :)

By the way, I know of the ISL but haven't got the foggiest about employing it in my day-to-day work; a histogram and a pair of eyes is just as effective a tool ;)
 
the trick for shooting manual in that kinda circumstance is to use Av then just set those settings in manual then adjust it to taste and never worry about something changing and the camera having a spazzy

I love flash, so much I'm spending my summer building a better trigger as part of my degree :D
 
Simmotino, don't fret *snip*

Thanks. I've fired off a few practice shots this morning with the flash on manual and I need to dial it down to about 1/64 to get it looking about right which seems really low, although it was indoors, so I guess you'd need a bit more 'oomph' outdoors to balance the ambient light.

I *think* we I may be getting somewhere here! :suspect::lol:
 
I'm with Garry & I love my speedlights too - so no bias there

You only have to use a flashmetre with any form of flash to soon realise the ISL is pants in the real world when discussing lighting (other than the top of Everest of course ;))

DD

I doubt whether anyone will be interested:'( but let me explain WHY I get a bit wound up about these 'tutorials' that pump out misleading info about the Inverse Square Law, or at least info that's misleading in the real world...

Bear in mind that I'm an old man and became a trainee professional photographer back in the days when we didn't have flash meters and our hotshoe flash guns used flash bulbs*, which were very expensive....
All we had were textbooks that explained the inverse square law. We had to measure distance between flashgun and subject and divide that into the guide number stated on the back of the packet of flash bulbs - which made assumptions about the efficiency of the reflector of the flash gun, which varied a lot, so there was a fair bit of real world testing involved.

Anyway, I found that exposures, based on real world application of the ISL were invariably way out, so I did my own testing, which involved a series of exposures in a wide variety of different environments at different variations from the 'right' f/number and using different powers of flash bulb (each of which needed to be used in a different flashgun because the different flashbulbs had different fittings and so needed different flashguns.

The film was then developed and the negatives examined to plot the differences in exposure between the real world testing and the exposure that the ISL dictated. Those differences were considerable.

That's why I'm unhappy about articles that mislead people by quoting the ISL.

*Actually we did have electronic flash then. The only one I knew about (there may have been others) had less power than a built in flash and had a separate powerpack which was carried on the shoulder. The powerpack carried lead acid batteries that weight a ton and only produced 40 flashes. The whole thing cost about as much as a cheap new car. That's why we used flashbulbs.

Todays' generation of digital photographers don't know they're born;)
 
I doubt whether anyone will be interested:'(

Just got home from a few days at the summer cottage, no electricity so a very nice break away from the hustle and bustle.

Just about finished catching up email wise and came across the developments with this thread.

I'm interested ;)

.....but let me explain WHY I get a bit wound up about these 'tutorials' that pump out misleading info about the Inverse Square Law, or at least info that's misleading in the real world...

Now, for the record, I have never used or attempted to use the ISL in any of my shoots, but one things seems to rub a little rhubarb here. :thinking:

Quite a few swear by it, not just any old sods, photog's who make a difference.

First things first, I'm going to make my own mind up about it but I do however feel the need to get one point nice and clear.

Because of the tests that you have done Garry 'back in the day', you find that the inverse square law is non applicable to lighting?

Furthermore, any photographer that suggests it has it's uses, is incorrect or misleading?

Todays' generation of digital photographers don't know they're born ;)

It's not too often I come into contact with folk who adopt this attitude, but, without wanting to make a generalization, you all do seem to have remarkably morose similarities.

Todays' generation of digital photographer...

Whether your picking up a camera for the first time in the digital age or if you have 'earned your stripes' back in the good old days of film, a fair few elements still separate the greats from the not so great, and the following but, albeit rough equation is unarguable.

No matter how aggressive or how rapidly technology advances in the world of the arts, you cannot subtract the human element.

Anyone who spews this 'Technology Has Made It Too Easy' manure around the place is in dire need of highly critical self analysis.

It merely quickens the pace and increases accessibility. Nothing more.

No one should feel any less of themselves simply because the technology was different in generations prior to their own existence.

True artists encourage progression and do not censure it.

...... don't know they're born ;)

The suggestion of stupidity, an elevation of oneself, whether a joke or stated with earnest, it means the same thing to me I'm afraid.

Not everyone will be as successful as each other but, photography is for everyone.

If the supporting act surpasses the quality of the headliner...

If the apprentice upstages his master....

If those who are unaware of their own births knock out decent photograph

=

So be it. :)
 
:plusone: :agree: Fantastic response .... Mr Whitehouse :thumbs:

I've been having my own trials and tribs Link Here for Reference with my new sb900 ...... if I thought I needed a physics degree to understand flash photography I might have thought twice ..... but i'm still determined to have some fun with it ...whether I get a decent pic from it is entirely not the point ..... I do photography for fun ...... :clap: and so far the sb900 in iTTL is giving me that. Once that fun element has gone then its for the real work to use and understand in manual.

Paul
 
Because of the tests that you have done Garry 'back in the day', you find that the inverse square law is non applicable to lighting?

Furthermore, any photographer that suggests it has it's uses, is incorrect or misleading?
Of course it has its uses. All I'm saying is that people need to actually read and understand it, not just quote it as an immutable law of physics. All I've tried to do is to point out that the ISL is a law of physics that applies to point sources of light in free space, and we hardly every use lighting in free space and never use point sources of light, therefore the ISL is just a guide that explains WHY the intensity of light diminishes over distance.


Quote:
Originally Posted by Garry Edwards View Post
Todays' generation of digital photographers don't know they're born
It's not too often I come into contact with folk who adopt this attitude, but, without wanting to make a generalization, you all do seem to have remarkably morose similarities.

Quote:
Originally Posted by Garry Edwards View Post
Todays' generation of digital photographer...
Whether your picking up a camera for the first time in the digital age or if you have 'earned your stripes' back in the good old days of film, a fair few elements still separate the greats from the not so great, and the following but, albeit rough equation is unarguable.

No matter how aggressive or how rapidly technology advances in the world of the arts, you cannot subtract the human element.

Anyone who spews this 'Technology Has Made It Too Easy' manure around the place is in dire need of highly critical self analysis.

It merely quickens the pace and increases accessibility. Nothing more.
As usual when you quote me, you seem to misunderstand what I'm actually saying.
What I'm saying is that 'back in the day' we had to carry out detailed, time consuming and expensive tests to find out whether the textbooks were right. Digital photography makes this testing process much easier but the downside of it is that a lot of people don't seem to see a need to put theories to the test, they just experiment to see what works and use a trial and error approach rather than a testing approach. That can't be a good thing because knowledge gained from testing is real knowlege and it sticks.

Having it easy isn't a bad thing, it's good. It makes photography more accessible and it makes it easier to learn quickly and cheaply. But new technology doesn't replace the need to learn
 
As usual when you quote me, you seem to misunderstand what I'm actually saying.

No, as usual, I understand you and your comments perfectly and I question them.

'As usual' you go onto to confirm my suspicions, see below.

What I'm saying is that 'back in the day' we had to carry out detailed, time consuming and expensive tests to find out whether the textbooks were right. Digital photography makes this testing process much easier but the downside of it is that a lot of people don't seem to see a need to put theories to the test, they just experiment to see what works and use a trial and error approach rather than a testing approach. That can't be a good thing because knowledge gained from testing is real knowlege and it sticks.

Which jusitifies:

Todays' generation of digital photographers don't know they're born ;)

See what I mean?

People still test theories, explore, find their feet, earn their stripes, source good info and make progress through practice.

No matter the technology, people still get up off their arse and work bloody hard.

Having it easy isn't a bad thing, it's good. It makes photography more accessible and it makes it easier to learn quickly and cheaply. But new technology doesn't replace the need to learn

No-one has it easy, it's just different to the way you had it.

When has anyone wanted to replace the need to learn and how on earth have you arrived at this conclusion?

This is my point Garry and believe it or not I'm trying to help a little here.

I've been a member of this forum for just shy of two years, I've come across quite a few of your posts, musings, advices and thoughts.

I find that you often use disparaging, contemptuous and derisive phrasing, which I happen to think is misleading, unbalanced and I can't ignore the notable presence of bitterness and contempt for contemporary methods/options/alternatives.

Of course the ISL law has its uses.

If the ISL law has it's uses then why this kind of useless and miserable response?
 
I reckon you're being a touch over sensetive here Tomas. Garry has put plenty of smillies in his posts indicating a touch of sarcasm or humour needs to be applied when reading it. You seem to have taken everything too literally and personally.

Your attitude towards Garry's opions on ISL are no better than what you claim he is saying about the source you referenced. He's got an opinion based on his own tests rather than readings someone elses work and you're not even slightly accommodating because it conflicts with your source.

As for his remark about digital photography being easy, it is. Good digital photography isn't.

I believe that to be a good digitial photographer is easier and quicker than it would have been when film was the only option. Now that isn't to say that it doesn't require hard work and skill but you can't deny the advantages to learning of instant feedback and virtually zero cost (excluding hardware and software, I'm talking materials here). You get the hump with anyone who has shot film pointing out the difficulties involved with it as a learning process but as someone who confesses to having never used a film camera you'll find it hard to fully understand why they're saying it.

PM me your address in Finland if you want, I'll send you the Lubitel when Joxby has finished with it, loaded with a roll of slide film and you can have a go at film photography for yourself to see the other side of the fence.
 
I reckon you're being a touch over sensetive here Tomas. Garry has put plenty of smillies in his posts indicating a touch of sarcasm or humour needs to be applied when reading it. You seem to have taken everything too literally and personally.

Sorry Kev, I appreciate your views but I disagree with your assessment.

I'm not taking this personally or being overly sensitive.

I would suggest to maybe read the thread which Garry saw fit to create. I think it explains my stance a little better.

Your attitude towards Garry's opions on ISL are no better than what you claim he is saying about the source you referenced. He's got an opinion based on his own tests rather than readings someone elses work and you're not even slightly accommodating because it conflicts with your source.

Sources could be a better word but no, I don't disagree with Garry because it conflicts with my sources. Garry's attitude conflicts with the method of getting the results.

I have my own opinion based on the comments, texts, posts and threads which Garry has contributed to. I compare the content, attitude with more balanced and less contented opinions and the results that the said methods yield.

As for his remark about digital photography being easy, it is. Good digital photography isn't.

Exactly.

I believe that to be a good digitial photographer is easier and quicker than it would have been when film was the only option. Now that isn't to say that it doesn't require hard work and skill but you can't deny the advantages to learning of instant feedback and virtually zero cost (excluding hardware and software, I'm talking materials here).
You get the hump with anyone who has shot film pointing out the difficulties involved with it as a learning process but as someone who confesses to having never used a film camera you'll find it hard to fully understand why they're saying it.

Yes, digital is quicker and also cheaper, making it more accessible as I mentioned above.
Yes, there are advantages but I really don't see any benefits or any rationality in having the 'hump' (as you put it) in any way, shape or form.

Technology is always going to change, and scolding folk (on any level) who now learn with or use more recent technology, is fruitless in the world of the arts.

The tech doesn't matter, if you want to be a great, you still have to get there.

That's also my answer to film only users who scoff and ridicule digital users.
If y'wanna use film only, then good for you but don't try to shove it down my throat or scoff at those who use digital or both.

Technology is just a vehicle in the world of the arts, no matter the speed of the engine, no matter how quick the fuel burns, there is still a human operating it and remarkable results rely on the human element.

"In my day it was a baked bean tin, a bit of string and magnetic tape, you lot don't know your born" is an attitude which we could all do without. :)

PM me your address in Finland if you want, I'll send you the Lubitel when Joxby has finished with it, loaded with a roll of slide film and you can have a go at film photography for yourself to see the other side of the fence.

That's a very kind gesture mate and I sincerely appreciate the offer.

I do have access to a darkroom and medium format camera's through our local camera club. I'm really looking forward to having a go, I know I'd learn a thing or too and it would be fun, but it's not going to be of detriment if I don't get round to it in a hurry in all honesty.

If you posted the Lubitel, it would be sitting there for yonks, gathering dust.

Before migrating here I saved hard and bought myself a Gibson Les Paul STD, I used to play guitar in a punk rock band, I've been playing for just over 16 years, I don't get much time to play anymore.

I'm trying to learn Finnish, I want to get a motor boat license and I also would like to go fly fishing more often too (I'm crap), I'd like to be thinner too, the list goes on.

I'm a lucky chap to have a job which I love, it's bloody hard though and time is not something I have too much of.
Plus I'm not even that good and I'd like to get better :lol:
 
:plusone: :agree: Fantastic response .... Mr Whitehouse :thumbs:

Cheers Paul although I really take no pleasure in making responses such as that.

Just trying to help out is all.

As for your lighting, fair do's.

Are you using the onboard flash to trigger your SB with the CLS system?

T.
 
No probs ..... I just thought your opinion was voiced very eloquently. I'm not taking on either side of the discussion as I can see both sides. I do think digital is more difficult than film in many ways as more is expected from digital, the main issue with film was that is wasn't always guaranteed. So more hit and miss.

Re: using my SB I am getting to grips with it slowly with the help of Dal who has had an SB800 for a while but I'm not at a stage yet to do any fancy stuff ...... i live in hope????

Paul
 
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