Light metering

Incident meters make the assumption that the subject is three dimensional and that light is reflected toward the cameras from it, in proportion to the visual tone.

It is not in the least interested in "How much light is reflected". It does not and can not measure this.

The Domes of incident meters were originally called "Heliospheres" which gives a clearer idea of their purpose.

Imagine a subject totally covered under a giant "Heliosphere" then bring up a side light.
You would note that Half the sphere was lit in a graduated fashion The side of the subject nearest the light would be lit full blast... but the front of the subject would only be lit by a fraction of that.
As you bring up more lights, so the Dome (and subject) would be lit variously by each light

The Dome on the meter works in just that way, when pointed at the camera each part of it is lit variously and in proportion to the lights hitting it. This light continues on to the Photocell which measures the "Total effective light falling on it, and that is available available to illuminate a 3D subject"

This measurement becomes a proxy for a perfectly reflective 3D subject and in proportion to its visible tones.

As you can see the meter would not give the same reading if it was pointed toward the light, as all the dome would be illuminated. Representing parts of the subject the camera would never see. It would also fail to achieve the the shot to shot standard required for studio or film work.

Back lights and hair lights tend to produce spectral highlights that will burn out, what ever the exposure set.
It is better to take readings with those turned off or ignored, and adjust those lights Visually or by ratio. The important tone and highlights will be maintained.
 
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EOS_JD said:
The guy that has taught me and Bryan has 11 UK Awards of Excellence; 59 Fuji Professional Awards; 112 British Professional Photographer Awards; 600+ Regional, National & International Awards and shows the work that proves his pedigree. We discussed use of the meter in one of our early sessions and he advocates meter to the light.

Was good enough for me and works.
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Sorry if you've already answered this, but just out of curiosity, who is the guy that taught you?
 
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EOS_JD said:
The guy that has taught me and Bryan has 11 UK Awards of Excellence; 59 Fuji Professional Awards; 112 British Professional Photographer Awards; 600+ Regional, National & International Awards and shows the work that proves his pedigree. We discussed use of the meter in one of our early sessions and he advocates meter to the light.

Was good enough for me and works.
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Some exceptional Photographers, Have a magic touch and produce outstanding results even when what they believe to be true, is only a half truth. They themselves are good enough to compensate for poor technical understanding with considerable experience.

The difficulty comes when others follow them religiously and believe what they are told is gospel.

Of course what you are saying will work, It is just that with a little more understanding it will work with a greater range of situations, with greater standardisation and with far fewer unexpected results.
 
If it was one guy saying this I might agree - but many highly respected photographers are saying the exact same thing and proving it. Read Frank Doorhoff and others....
 
Kenny Martin is another who says point to the light, do what works for you, I think photographers who train should lead by example and not hide behind BS
 
Like I said Bryan proof in the pudding.

You're not bad yourself!
 
Terrywoodenpic said:
An Incident meter can give answers to two questions ...
I) the relative powers of the light coming from each light, to set up ratios. (use the flat screen)
2) To measure the The Incident light Falling on the subject. point the light at the camera from the position of the subject, Using the domed head.
(the domed head is shaped so that it pick up light in a 180 degree arc. this enables "some" of the side light to be taken into account as well as the main light.

A third method was to take duplex readings. For this point the meter( from the subject) at the main light and take a reading. Take a second reading pointing at the camera. Then average the reading. This often gives better results in strongly side lit situations.

Incident meters were always used for film work, Indeed the first Sekonic was called the Norwood director (I still have one) In film work it is important that each scene is balanced with the next. Incident readings ensure that this is so. Film work also needs to be lit for depth... that is to say as the subject moves about you don't want him to become darker and lighter. For this reason readings were taken along the entire "Walk" and balanced with lighting.


Incident reading are in most cases more accurate than reflected readings, and preserve key-tones. Relative brightnesses of the subjects are accurately preserved.
A Black skin looks black and a light one light.
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Terry, alas, it seems there is no point in explaining this subject properly unless you have an answer where people don't need to think. Until they build in a flash meter into the cameras that makes the decisions for them, they will argue until the cows come home

On that note my new stock answer is...

Set the lights to whatever setting you like, meter anything you like, chimp and fix everything in Photoshop. It would be best to do this for each shot. For multiple shots, of different subjects where things don't match, a hour or so in Photoshop will get them near enough OK

If everyone can follow this advice, it will at least mean more jobs come my way, as all the other photographers will be bogged down with post,and clients will be looking to get a decent job done

If peeps find this all a bit hard, then the second and clearly better option is to use continuous lighting and settle for wysiwyg... again one can use PS to fix everything, and if one ends up with a shot requiring movement, either clone the mess out in Photoshop, or send the customers my way

Tongue firmly back in cheek...
 
Richard King said:
Terry, alas, it seems there is no point in explaining this subject properly unless you have an answer where people don't need to think. Until they build in a flash meter into the cameras that makes the decisions for them, they will argue until the cows come home

On that note my new stock answer is...

Set the lights to whatever setting you like, meter anything you like, chimp and fix everything in Photoshop. It would be best to do this for each shot. For multiple shots, of different subjects where things don't match, a hour or so in Photoshop will get them near enough OK

If everyone can follow this advice, it will at least mean more jobs come my way, as all the other photographers will be bogged down with post,and clients will be looking to get a decent job done

If peeps find this all a bit hard, then the second and clearly better option is to use continuous lighting and settle for wysiwyg... again one can use PS to fix everything, and if one ends up with a shot requiring movement, either clone the mess out in Photoshop, or send the customers my way

Tongue firmly back in cheek...
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I was thinking the same Richard :)
 
Richard King said:
Terry, alas, it seems there is no point in explaining this subject properly unless you have an answer where people don't need to think. Until they build in a flash meter into the cameras that makes the decisions for them, they will argue until the cows come home


Tongue firmly back in cheek...
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I find it very hard to keep quiet After a lifetime in the business, and having used Incident meters since they became available in the 50's

It has got worse since the web was invented, as misinformation now spreads so fast. "Experts" no longer think ... they just regurgitate what someone else has written.... Within days "rubbish" becomes "Truth".

Even this thread will soon be used as proof of nonsense.
 
So what makes you right and them wrong? These are guys who are not just photographers from the digital age saying this. Professional highly regarded and decorated photographers that are at the top of their game.
 
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EOS_JD said:
So what makes you right and them wrong? These are guys who are not just photographers from the digital age saying this. Professional highly regarded and decorated photographers that are at the top of their game.
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All of the high end professionals that I know of are far too busy to enter, let alone win, 600 "awards", and certainly wouldn't crow about any such record as demonstration of their capabilities as a photographer (or a light meter-er for that matter), partly as to do so would make them a laughing stock among people who make the majority of their living from taking pictures.

Fwiw, I'm a freelance photo assistant. A very common part of my job is metering. Many different photographers have slightly different ways of metering, but basically... Garry is right (as much as that hurts to say! ;) )
 
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Dave
Any photographer looking to advertise themselves should be crowing about everything they get!

How on earth can it be right if you don't meter the light hitting the subject? You may "think" he's right but he's not shown one thread of evidence to support the statement in imagery!

What high end professionals would you be talking about Dave?
 
(Caution:generalisations and amateur insomniac 4am ramblings ahead) Terrywoodenpic above put it quite neatly.


You want to measure the light actually hitting the subject, not the light being chucked out from each individual source....(with the exception, as Garry clearly put it, of hair or other effects lights - though with digital, chimping these is often the better plan anyway)

Think of the dome on your meter as your subject's face if you will, for metering most basic situations with relatively flat light. Not all of the face sees all of the light, and pointing the dome towards the camera (or the same direction that the subjects face is pointing) means that you're metering for the right geometry (approximately) of the light hitting the subject.

Some people in this thread are wayyyyyyyy over thinking it, go out and take pictures! With digital, many people don't even meter externally at all...
 
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That's incorrect - Why do you want an approximation of the light hitting the subject? If you measure the light hitting the subject from the front, surely you will then more than likely over expose the point nearest the light source as you have no idea what that is. A side lit subject a backlit subject - again measuring from the front makes absolutely no sense whatsoever.

Measuring the subject towards light source means YOU have the control. You may make a creative decision to open up the shadow area at the expense of highlight or you may add fill to reduce contrast or well anything but at least you know the amount of light hitting the subject at the point you want to measure the light rather than an approximation.

The bit I don't get is where the camera moves - if I am shooting a subject and I move, (with the light in the same position) the exposure on the subject has not changed in any way - Yet if you meter towards the camera every shot where you have moved would likely give a different result even though the light hasn't moved. :bonk:

Frank Doorhoff's blog explains it better than me.
 
EOS_JD said:
That's incorrect - Why do you want an approximation of the light hitting the subject? If you measure the light hitting the subject from the front, surely you will then more than likely over expose the point nearest the light source as you have no idea what that is. A side lit subject a backlit subject - again measuring from the front makes absolutely no sense whatsoever.

Measuring the subject towards light source means YOU have the control. You may make a creative decision to open up the shadow area at the expense of highlight or you may add fill to reduce contrast or well anything but at least you know the amount of light hitting the subject at the point you want to measure the light rather than an approximation.

The bit I don't get is where the camera moves - if I am shooting a subject and I move, (with the light in the same position) the exposure on the subject has not changed in any way - Yet if you meter towards the camera every shot where you have moved would likely give a different result even though the light hasn't moved. :bonk:

Frank Doorhoff's blog explains it better than me.
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It seems that you do not understand either what an incident meter is measuring or how view point effects the outcome.

I have already explained what it measures in previous posts.
The camera position effects the outcome because it is what the camera actually sees, it is the only important illuminated part of the subject.

If you illuminate a Ball with a single light 90° to the right of the camera. Half the ball will be lit and half not with a large penumbra separating the two halves.
If you leave the light and ball exactly where they are, but move the camera to the right, More of the ball will be lit with the penumbra forming a smaller visable proportion of the lit area.
If you move the camera to the left the reverse is true.

Unlike a Reflected light meter an incident meter is calibrated and designed to take cognisance of the Penumbra.

This is the exact same phenomena that is measured by the dome when pointed at the camera.

However as I explained in my first post this particular circumstance with the light coming from a single extreme side position, is some times better served by using a duplex reading.

Light is the essence of photography and is worth spending time understanding it.
 
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EOS_JD said:
So what makes you right and them wrong? These are guys who are not just photographers from the digital age saying this. Professional highly regarded and decorated photographers that are at the top of their game.
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The logic and science say I am right. it is also the way Incident meters are designed to function.
I am not confined to the Digital Age, I started photofraphy in the 1940's studied Photography in the 1950's and was a professional till I retired. I inported my first Incident meter from the USA in 1956 (before they were generally available here.)

The concept of "Decorated Photographers" is a new one.
Until recent years the only awards available were the respected professional qualifications.
The exception came with the introduction of the Press awards.
Other professional photographers were neither interested nor saw such trifles as advancing their reputations one iota.

In recent years such awards have proliferated as part of social media expectation.
They are still as meaningless as always, but I do not blame photographers playing the game. The down side to awards is that become an end in themselves, and take your attention away from from the real income creating business of photography. A majority of professional Photographers have never entered for an award.
 
itsdavedotnet said:
All of the high end professionals that I know of are far too busy to enter, let alone win, 600 "awards", and certainly wouldn't crow about any such record as demonstration of their capabilities as a photographer (or a light meter-er for that matter), partly as to do so would make them a laughing stock among people who make the majority of their living from taking pictures.

Fwiw, I'm a freelance photo assistant. A very common part of my job is metering. Many different photographers have slightly different ways of metering, but basically... Garry is right (as much as that hurts to say! ;) )
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Just as an aside, I once entered a competition myself, it was a specialised one limited to professional advertising photographers.

Back then, I was working as an assistant. The client was a government quango called (I believe) the Location of Offices Bureau, or something similar. Their job (and ours) had been to persuade businesses to move out of London, and the campaign had been so successful that they started another campaign to get them to move back:)

Anyway, we did a series of bland shots, which they used. I had an idea that my boss ran with, which was a bit quirky and maybe a bit too creative, or so I thought...

The theme was to be "The streets of London are paved with gold".
I set up the shot with a "prostitute" standing outside Piccadilly Circus tube, posing provocatively. It was pouring with rain (but we had taken loads of water with us in case the weather had been dry) and photographed her with the wet pavement etc behind her, and with puddles of water. I stuck a Letraset (anyone remember letraset?) £ sign upside down on a UV filter and took the shot, on 5"x 4".

As every photographer knows, any obstruction to a lens will appear in every highlight in the shot, so the £ sign showed up in every puddle, every bit of wet pavement, and even on the model's shiny plastic miniskirt...

If I say it myself, it was a cracking shot. The client ran with it, against all expectations, but it was a mistake, the campaign bombed and they dropped my photo and used the bland ones instead. My boss entered it in the competition and it won 3rd prize. I was famous for about 15 minutes...

I believe that 1st prize went to the famous "You're never alone with a Strand" fag advert, with the smoker standing on Blackfriars bridge. That ad campaign failed too. Generally, the photos that do well in competitions don't work...

That was the only competition I ever entered.

As young Dave says, most photographers have better ways of spending their time.

A lot of people have spent a lot of time explaining why the results are nearly always better when we meter to the camera, in both this and other threads. It's just very basic physics, and it's very difficult to understand lighting without having at least some understanding of the physics of light.

BTW, re "Terrywoodenpics" posts - in my experience, the professional movie lighting guys are the absolute best when it comes to lighting. They have to be, because they have to deal with depth as well as with having a fixed shutter speed, movement and everything else. If a movie lighting guy gives advice on lighting, listen to what he says.
 
Garry Edwards said:
BTW, re "Terrywoodenpics" posts - in my experience, the professional movie lighting guys are the absolute best when it comes to lighting. They have to be, because they have to deal with depth as well as with having a fixed shutter speed, movement and everything else. If a movie lighting guy gives advice on lighting, listen to what he says.
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Yup. Moving pictures brings a huge amount of its own extra challenges :) always great to see and work on film/tv sets for this reason (that and the catering...)
 
Richard King said:
Terry, alas, it seems there is no point in explaining this subject properly unless you have an answer where people don't need to think. Until they build in a flash meter into the cameras that makes the decisions for them, they will argue until the cows come home
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So that the camera reads reflected light? I thought that's why we use flash meters to measure the incident reading (the light falling on the suibject)!?

Don't like the tone though Richard I expect more from you.
 
Terrywoodenpic said:
It seems that you do not understand either what an incident meter is measuring or how view point effects the outcome.
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My thoughts exacltly reversed - An incident meter measures the light falling ON the subject - Not reflected to the camera!

Terrywoodenpic said:
If you illuminate a Ball with a single light 90° to the right of the camera. Half the ball will be lit and half not with a large penumbra separating the two halves. If you leave the light and ball exactly where they are, but move the camera to the right, More of the ball will be lit with the penumbra forming a smaller visable proportion of the lit area. If you move the camera to the left the reverse is true.
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I'm in agreement there

Terrywoodenpic said:
Unlike a Reflected light meter an incident meter is calibrated and designed to take cognisance of the Penumbra.

This is the exact same phenomena that is measured by the dome when pointed at the camera.
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Are you suggesting that the shadow side of the ball we meter towards the camera? Of course we don't as that would give a wholly false reading

Meter to the light source and as you move around the ball the exposure of the lit side will stay consistent - it can't be over/under exposed as you have measured the intensity of that single light source. As you move around the camera the exposure remains consistent - no need to change

If you re-meter every time you more the camera and meter to the camera every exposure would be different! How many do that with their models? - None

Terrywoodenpic said:
However as I explained in my first post this particular circumstance with the light coming from a single extreme side position, is some times better served by using a duplex reading.
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Why? You already know the reading from the main light source - That area should be in deep shadow. Why would you change it (notwithstanding creative effect)

Terrywoodenpic said:
Light is the essence of photography and is worth spending time understanding it.
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I agree.
 
EOS_JD said:
So that the camera reads reflected light? I thought that's why we use flash meters to measure the incident reading (the light falling on the suibject)!?

Don't like the tone though Richard I expect more from you.
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Jim, I keep saying this, and so do other people...

Using the meter correctly, i.e. pointing towards the subject, what we are metering is incident light (light incident upon the subject, but as reflected towards the subject.

Your method is measuring incident light but takes no account of light lost in reflection towards the subject due to the effect of cosine law.
 
But we're not measuring the reflected light otherwise again you would get different readings for light skin as compared to dark skin at the same intensity of light. Reflectance is not the issue.

Garry Edwards said:
Using the meter correctly, i.e. pointing towards the subject,
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Gary, you say pointing the meter towards the subject???
 
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EOS_JD said:
But we're not measuring the reflected light otherwise again you would get different readings for light skin as compared to dark skin at the same intensity of light. Reflectance is not the issue.
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YES IT IS!
As everyone keeps saying, we are measuring the incident light that is reflected towards the camera - not that is bouncing straight back towards the light...

EOS_JD said:
Gary, you say pointing the meter towards the subject???
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A typo, obviously. I meant to write pointing towards the camera.

EOS_JD said:
A great video

http://www.youtube.com/watch?v=f3CTJ...ature=youtu.be
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You mean the bit at the end where the cat is walking down the stairs?
Other than that, he simply confuses watchers by an irrelevant mention of the inverse square law and also misunderstands the basic physics involved.

Don't take his word for it, or mine, or any of the other people who have tried, time and time again to explain this to you - just think about it, and the way that light behaves when is reflected from a surface towards the camera.
 
Garry Edwards said:
YES IT IS!
As everyone keeps saying, we are measuring the incident light that is reflected towards the camera - not that is bouncing straight back towards the light...
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An incident meter reading does not measure light reflected at all? It measures the intensity of the light falling on that particular area.


Garry Edwards said:
A typo, obviously. I meant to write pointing towards the camera.
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I thought that.

Garry Edwards said:
Other than that, he simply confuses watchers by an irrelevant mention of the inverse square law and also misunderstands the basic physics involved.
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But the inverse sq law describes it perfectly.

Garry Edwards said:
Don't take his word for it, or mine, or any of the other people who have tried, time and time again to explain this to you - just think about it, and the way that light behaves when is reflected from a surface towards the camera.
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That's where I can't understand the point. I don't get that you are taliking about reflected light when that is wholly irrelevant. If I meter to camera position again it's the light falling on the meter that is measured - not reflected to the camera as the position of the camera is irrelevant.

Sorry that I'm not getting your point at all.
 
Taken from the web and I get this.

Incident light meters - a handheld light meter which measures the light falling on the subject. Incident meters are not influenced by the subject's reflectance.
 
(y)
 
Phil Bennett said:
Just wondering if the OP is any the wiser?

Phil
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I very much doubt it to be honest it is totaly stupid now with all this tit and tat remarks :wacky::wacky:

With a bit of luck the mods will lock the topic soon :rules:

Ian
 
EOS_JD said:
A great video

http://www.youtube.com/watch?v=f3CTJJ2uVyg&feature=youtu.be
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If what you want is to measure for the highlights only, what he is saying is not far from the truth.

However that is not what you want, what you want is to set an exposure that that covers an entire range of tones. The shape and make up of the dome is designed to measure the light falling on each part of the surface and give you a balanced tone every time. If you point it at the light you only measure for the highlights. In fact if you point at the light source, you might as well just use the flat screen rather than the dome as you would get the same result. The dome is designed to catch light coming from all angles, that is only necessary when you point at the camera and is more accurate, as it takes into account all the light falling on to the face of the subject as seen from the camera.
A dome is not the only structure that will do this, If you look at the "Weston" invercone, they use an inverted cone, which works just as well.
You can also do an experiment with any ordinary reflected light meter. ( I discovered you could do this when I was 15) Point the reflected meter at the main light source and take a reading in the normal way. If you reduce the exposure by 4 1/2 stops and set that on the camera you will have a near enough exposure. Before exposure meters were as sensitive as they are now, this allowed you to take readings at very low light levels. and was a sort of forerunner of incident readings
 
Iain since when did you become a moderator? Report the thread if you are not happy.

I don't think anything particularly bad has been said by anyone?! Yes a few wee niggles but nothing taken to heart I would hope by anyone who posted.
 
If you read what i said i never said i was a moderator i will take you're advice and report it then

Oh and also there's only one I in my name thanks
 
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Terrywoodenpic said:
If what you want is to measure for the highlights only, what he is saying is not far from the truth.

However that is not what you want, what you want is to set an exposure that that covers an entire range of tones. The shape and make up of the dome is designed to measure the light falling on each part of the surface and give you a balanced tone every time. If you point it at the light you only measure for the highlights. In fact if you point at the light source, you might as well just use the flat screen rather than the dome as you would get the same result. The dome is designed to catch light coming from all angles, that is only necessary when you point at the camera and is more accurate, as it takes into account all the light falling on to the face of the subject as seen from the camera.
A dome is not the only structure that will do this, If you look at the "Weston" invercone, they use an inverted cone, which works just as well.
You can also do an experiment with any ordinary reflected light meter. ( I discovered you could do this when I was 15) Point the reflected meter at the main light source and take a reading in the normal way. If you reduce the exposure by 4 1/2 stops and set that on the camera you will have a near enough exposure. Before exposure meters were as sensitive as they are now, this allowed you to take readings at very low light levels. and was a sort of forerunner of incident readings
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Terry are you therefore saying that the highlights are not important? If you meter for the highlight being the brightest part of the image it makes sense that the rest of the image will fall into place. You can control the fall of light in other areas through the use of additional lights such as the fill light.

Also you may want to choose how bright the highlight is (again a creative decision)
 
EOS_JD said:
My thoughts exacltly reversed - An incident meter measures the light falling ON the subject - Not reflected to the camera!



I'm in agreement there



Are you suggesting that the shadow side of the ball we meter towards the camera? Of course we don't as that would give a wholly false reading

Meter to the light source and as you move around the ball the exposure of the lit side will stay consistent - it can't be over/under exposed as you have measured the intensity of that single light source. As you move around the camera the exposure remains consistent - no need to change

If you re-meter every time you more the camera and meter to the camera every exposure would be different! How many do that with their models? - None

Why? You already know the reading from the main light source - That area should be in deep shadow. Why would you change it (notwithstanding creative effect)



I agree.
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This is where I step out.... It is clear that you do not wish to think about what I am explaining ( perhaps I am not being clear enough for you)
One day you may come to realise that what I have been explaining is true.

Just try and think about a few things... why is the sensor covered with a dome for incident readings and with a flat for taking ratios?
Then think why you might want a proxy for a three dimensional subject, in the form of a light collecting dome?

The answer to those questions led to the design and correct use of the Sekonic meters.
 
My head hurts a lot. Terry's last post is correct and covers why and when both ways of metering work.
 
Sekonic's own site states

"Advantages of Incident Meters

A better alternative to reading the light in many scenes is to use an “incident” meter. Handheld incident meters read the intensity of light falling on the subject and are usually taken from the subject position. Because they are not affected by variances in subject color or reflectance, incident meters accurately record the amount of light falling on the subject. In the majority of situations, an incident reading is extremely accurate and records tones, colors, and values correctly."

By metering anywhere other than to the light you are not metering the light falling "on" the subject.
 
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