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Cheers gents
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Light metering
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I always meter for the light, as it's a light meter but what ever works for you, it's very simple and same logic applies , you throw a bucket of water at some one and you want to know how much water has hit them , would you meter the water before it hits them or meter the water after its fallen off them, before obviously as depending on what there wearing will determine the water fall off ie someone wearing a wooly jumper will retain more water than someone in a wet suit, light is the same someone in mostly white will reflect more light than someone in mostly black.
Most of the time pointing to camera or light will give a very similar exposure 1-2 10ths of a stop really ain't much. How ever in my opinion pointing to camera is bad practise and in a natural light situation you can very easily Meter for the shadow rather than for highlight
As for histograms anyone who says they can tell if a subject is correctly exposed or not from a histogram is an idiot as most of the time you can't get a text book histogram due to the mostly light or mostly darkness areas of a scene in a picture which has no effect on the exposure of your subject.
Most of the time pointing to camera or light will give a very similar exposure 1-2 10ths of a stop really ain't much. How ever in my opinion pointing to camera is bad practise and in a natural light situation you can very easily Meter for the shadow rather than for highlight
As for histograms anyone who says they can tell if a subject is correctly exposed or not from a histogram is an idiot as most of the time you can't get a text book histogram due to the mostly light or mostly darkness areas of a scene in a picture which has no effect on the exposure of your subject.
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Using the histogram is the difference between 'correct' exposure and 'optimum' exposure. A meter, used porperly, will usually give you the former, but only the histogram (preferably with blinkies enabled) can give you optimum exposure with digital. This is the basis of ETTR technqiue (Expose To The Right).
And you can use the histogram for 'correct' exposure reading. I often do, though it can be tricky outside of a studio environment. Just get the subject to hold a large grey card (eg Lastolite EzyBalance http://www.lastolite.com/ezybalance.php ) and it's a simple matter to identify that as a peak in the histogram.
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Interesting to see Garry that when you take reading you held it at the side closest to the light, ie the same as pointing at the light source. How different would your reading be if held on the shadow side of the face?
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you have never mentioned using a grey card until now, thats very different to using the histogram without a grey card (which is what you had led us to believe)
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Obviously that's where it goes. The metering process measures the light that reaches the subject and which then goes towards the camera - the basic fact that you are arguing about...
Therefore, it needs to be where the light reaches it. If the reading was taken from the shadow side of the subject it wouldn't get most of the light, so the reading would be way out.
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And you never mentioned the absense of a grey card, not exactly an unusual exposure aid, before labelling everyone an idiot.
I'm not saying the histogram/LCD/blinkies is the asnwer for every situation or that other ways of working are not perfectly serviceable. But exposure is a tricky business if you want to get it exactly right, so I use every tool I can.
Example: I was doing some tabletop yesterday, including a black handbag and sunglasses. It was important to get as much light as possible into the darkest areas of the bag, without blowing the prominent specula highlights reflecting off the sunglasses. Using the histogram/LCD/blinkies I was able to ensure everything was optimally exposed within the sensor's dynamic range. A meter would have been no help at all in getting that precisely as good as it could be.
Edit: since the lights are still set up, I just thought I'd compare a meter reading to my actual exposure. Meter says f/16d1, and I used f/11 so that put over one stop more light into the shadow areas, very welcome, without blowing the highlights. (Key light was fairly frontal, so metering towards the light/camera make no difference here.)
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from someone who is new to photography they would have assumed that you just take a picture, read the histogram and adjust accordingly as thats how you came across,- Messages
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to me you have essentially metered towards the light source
our exposures would be very similar if not the same
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How the hell do you come to that conclusion?:shrug::shrug::shrug:to me you have essentially metered towards the light source
our exposures would be very similar if not the same
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Garry Edwards said:
Because I watched your video clip!
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How did he get it wrong? SS makes no difference and as Richard says the initial setting he showed he explained what it was about. THe second time he showed it that was the settings he used - but whether 1/60th or 1/125th it makes no difference (but I agree to a beginner that could be confusing showing different settings).
I still cannot see any reasonable argument for not measuring towards the light?
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The histogram just shows you the distribution of light within the image, the very left and right sides of which approximatally indicating the limits of your camera sensor
However...
If you set up your lighting, and then did not change the lighting for the next 10 shots, and put 10 subjects in, ranging from mainly matt black through to mainly gloss white, you would expect the shape and position of the lines on the histogram to change depending on what subject was under that lighting.
If you are the sort that sets up lighting using a histogram, then, if the first object was matt black, the rest of your shots would be over exposed. This is why using the histogram is only helpful if you do not need consistency from shot to shot. If you had to shoot 10 models and 200 dresses on the same background for a catalogue, the editor would not thank you for changing the lighting a lot (in terms of overall power) because you are going on what you think looks right on the histogram. The editor will want a consistent background, and properly exposed dresses and models
Metering the grey card is the "known compromise" experientially you are measuring the illumination, after it has been reflected off a card which is chosen to be fairly representative as "normal"
Metering to the camera however is simply an indication of illumination, and has one step or chance of error removed from the measurement process
The reason why we meter to the camera, and not to the light is because of the laws of optics, namely the laws of reflection
The intensity of the reflection is given by Fresnel's equations
Fresnel shows that as we change the angle of reflection, the amount of light reflected changes. The unreflected light is absorbed or transmitted through the medium. Fresnel's equations show us that if we light the subject fairly obliqley, we would expect comparitivley less light to get to the camera than if we say used a ring flash
By metering to the camera, we are essentially nodding to 2 fundamental simple optical principles..
Fresnel's equations of reflectivity and the reversability of light in a system
Metering to the light ignores the loss in illumminance from the cameras point of view from any light that is not on the same axis as the camera
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How can that possibly be true?
Exposure is not about light falling on the subject, nor even about light reaching the camera. It is only about light falling on the sensor. They are often very similar, even the same, but can also be very different.
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It depends on why you are taking the measurement
For one shot, in isolation, what falls on the sensor might be totally relevant. For a series of shots that have to match, the light falling on the subject and background are totally relevant
For fear of repeating myself, let us say you have to shoot 10 models in 10 different colour dresses, ranging from a black girl in a matt black dress through to a white girl in a white shiny dress
Your brief is that they all are going to be shown on the same catalogue page, and the backgrounds need to be consistent throughout
If you set up for the histogram on the first model, you will be out by the time you shoot the last model
At best, you can use the histogram, do a test shoot for the first and last model, and go for a setting in-between
The histogram does not know if you deliberatally want a high key or a low key shot, nor does it know how reflective the subject is
Back in the real world we all hopefully use a range of the the tools in the box, histogram, light-meter, incident or reflective readings
I suppose the difficulty here is that the incident reading seems so abstract that some refuse to grasp its value. The value of an incident to the camera reading is consistency
This page here describes the pitfals of relying only on the histogram / reflective readings
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So lets say you measure the light falling on the subeject at f8. You're shooting from 8" - it will be f8, from 2 feet it will be f8 from 10 feet the settings will still be f8 yet the amount reflected in each scenario will be different.
It's about the light falling on the subject
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You're not taking this in. The light reflected off a subject, it's brightness as seen by the camera and therefore a good basis for exposure, varies with angle. If it's lit dead square, which is what you meter straight at the light, you'll get one figure, but that changes at different angles of reflection - cosine law.
Example, a human face, that has even toned skin, but what we see is brightness varying over cheeks and noses and foreheads, because they reflect differently. It's highlights like this, and shadows, that reveal shape and texture.
The other variable is the light that falls on the lens is not necessarily the same as received by the sensor. That changes according to the lens' T/stop vs f/number, can be further altered by the accuracy of the actual diaphragm setting, and a third variable is the calibration and dynamic range of the sensor.
These may not always make much difference, not a significant one anyway, but they most certainly can do. The histogram is the only way of knowing what's actually going on (and I'm not saying the histogram is the answer for everything!).
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This is getting boring, however as Jim says we aren't talking about reflected light, we are talking about light falling on a subject and regardless of the angle we take a picture from the amount of light hitting the subject doesn't change. However as we change our angle to photograph so should the light in order to maintain a recognisable lighting pattern which is suitable for our subject at that given time.
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What is boring, is post after post missing the point.
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If your interested in reflected light then why use an incident meter ??? Surely a spot meter is what would suit you best, me I'm interest in the light falling on my subject do use an incident meter
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All flash meters are incident meters, although they can also be used in reflective mode. Incident readings are far more likely to be accurate than reflective readings, the only reason that reflective meters are used at all is that they are the only type that can be built into cameras, which of course can't be used with studio flash. The only common exception to 'incident is best' is when hairlights are used when shooting on film. When shooting on digital, there's little point in measuring the hairlight at all.
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Garry Edwards said:
That's just rediculous and I like your comment from your video clip " if the light is at an extreme angle point the meter at the light" make your mind up will you
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Not rediculous (or even ridiculous) at all.
A hairlight is an effect light, nothing more.
An incident reading of a hairlight is pretty pointless because different hair reflects light very differently.
Natural blond hair is about twice as fine as brunette hair
Red hair is somewhere between the two.
Clean hair in good condition reflects far more light than dirty hair, or hair in poor condition.
Hair treatments/preparations make an enormous difference too.
Afro hair just soaks up light and reflects hardly any light.
Therefore, an incident reading is pretty pointless. That's why we tend to use reflective readings when necessary - if we are shooting on film without the benefit of polaroids.
But if we are shooting on digital, or on polaroids, it's usually much better just to experiment, to get the level of brightness that we actually want, rather than some theoretical and elysian standard of perfection that may not give the effect that suits the shot - which is why the usual "expert advice" such as overexposing the hairlight by a half stop is just nonsense.
As for
that refers to a light that is coming from behind or very nearly so. In that situation, pointing the meter at the light will give some kind of reading that can then be interpreted to give a meaningful result (it won't of course give any kind of accurate reading because of the effect of cosine law) but it will at least give some indication, and some is a bit better than none.
What you need to do, if you really want to understand this, is to read the detailed explanations provided, several times over, by people such as Richard Hopkins and Richard King. All the information you need is there. It's very, very simple physics.
It's best to ignore statements made in promotional videos designed to sell products, and statements made by people who teach photography for a living instead of doing photography for a living. Unfortunately, there is far more *******s out there on the web than facts.
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I agree that different hair colour etc will take light differently that's why you need to know how much light is hitting it, I would accept someone saying they know there equipment and know that at a said power at a set distance would give them the look there after is fine, it doesn't need to be exact, but there will be a big difference from a hair light set at full power when compared to a hair light set at 1/4 power hence why you need to meter. Obviously you need to know what you want To achieve and know your ratios , hence why experience is king, wouldn't you prefer to get it right first time instead of chimping?
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No, it's because different hair reflects light (very) differently that you need to know how much light is reflected from it, not how much light is hitting it.
If that was possible, yes. But it isn't. Personally I much prefer looking at the image on the laptop and judging whether or not it's what I'm looking for than working to some kind of formulae and getting bland results.
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Why not just ditch the light meter completely and just pray for a half decent picture!
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I would defy anyone to read exactly what the histogram is telling them. Sure you can watch the highlights and shadow areas and get a "rough idea" but that is nowhere near enough accurate.
Take meter press button pointed at each light in turn bam..... light intensity for each light sorted.
What's harder?
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Exactly what I think both Bryan and myself have done and by guys who show the images they take.
And one that is noted above - is Frank Doorhoff a poor photographer only teaching? I think not.
I can assure you the guys who have taught (and are teaching) me are qualified to do so and are still producing fantastic work (one with a pretty high profile in the photography world). Same guy that also taught Bryan I believe.
And Garry, how do we know you're any better or worse at teaching? You never (or very very rarely) show any work here?! The guys I'm talking about post their work constantly.
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There was a time when my photography was my hobby as well as my work. Back then, I did a lot of black & white large format for pleasure, but no more.
What I'm left with now is purely advertising and commercial work. Pretty much all of it is embargoed for months after the shots have been taken, and even when it isn't embargoed, I'm not going to risk upsetting important clients by publishing their work without permission, even though technically I don't usually need their permission.
And I don't photograph pet spaniels, weddings, cute kids or pretty girls so most of what I shoot is of very little interest, other than on a purely technical level.
And I have no need to self-publicise by constantly posting my work anyway.
So, you either accept that I know what I'm talking about or you don't, it's your choice.
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Well you were kind of inferring that Bryan (or we) were taking training from people who only teach and are not working photographers which is in fact the complete opposite and also inferring that we are being trained by *******s?!
My question is asked because we never see your work which as someone who trains I find very odd. You must have a huge collection of work that you can show - You do training workshops.... What stops you posting images from there?
When you look at someone like Frank Doorhoff you can see the proof is in the pudding
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No, I wasn't inferring anything.
What I said was that a lot of the people who teach, only teach.
This may be because they are excellent teachers. Or it may be for some other reason, for example because they can't hack it as photographers. If that's the case, it doesn't necessarily mean that they don't understand the basic principles, but it's clear that in many cases, they don't.
At Focus this year I saw a demo (repeated many times) by a famous name who was selling a specific bit of kit. The demo was very, very smooth, a wonderful presentation in fact - but it was obvious from just a quick glance that the photos he displayed on the screen weren't live - they were shots taken earlier, processed and retouched, and then displayed in a carefully choreographed demo that made them look genuine. Strangely, none of the public watching these displays seemed to realise that... It isn't difficult to deceive people on a demo, or on a training course. And training videos make it even easier to deceive.
For the avoidance of doubt, I'm not saying that all trainers are rubbish, nor am I saying that everything on the web is rubbish. But a lot is.
What I said was that a lot of the people who teach, only teach.
This may be because they are excellent teachers. Or it may be for some other reason, for example because they can't hack it as photographers. If that's the case, it doesn't necessarily mean that they don't understand the basic principles, but it's clear that in many cases, they don't.
At Focus this year I saw a demo (repeated many times) by a famous name who was selling a specific bit of kit. The demo was very, very smooth, a wonderful presentation in fact - but it was obvious from just a quick glance that the photos he displayed on the screen weren't live - they were shots taken earlier, processed and retouched, and then displayed in a carefully choreographed demo that made them look genuine. Strangely, none of the public watching these displays seemed to realise that... It isn't difficult to deceive people on a demo, or on a training course. And training videos make it even easier to deceive.
Because I teach other people how to do it, and then get them doing it themselves, which kind of proves that my teaching works. A lot of people on this forum have been on the lighting workshops run on behalf of Lencarta, they will all confirm that I don't take any photos during the day.
For the avoidance of doubt, I'm not saying that all trainers are rubbish, nor am I saying that everything on the web is rubbish. But a lot is.
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Mr G said:phew that was hard work reading that guy's
I know I'm no better versed for it
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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.
Was good enough for me and works.
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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.
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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