Do I really need a grey card?

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Archive 2009 · Do I really need a grey card?

cineski
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p.2 #1 · Do I really need a grey card?

This is all I've ever used. Oh wait, I do have a Gretag McB card, but don't use it.

Daan B wrote:
dmacmillan wrote:
I use the WhiBal card. It's a calibrated grey. I don't use it (nor should it be used) for exposure.

Me too... with good results

Oct 20, 2009 at 10:09 PM

Future Man
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p.2 #2 · Do I really need a grey card?

I just wiggle the WB slider in Lightroom and don't think about this shit when I'm shooting.

(JOKE post... but yea, it's actually what I do now... Maybe when real color accuracy matters I'll start using a grey card)

Oct 20, 2009 at 10:27 PM

dmacmillan
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p.2 #3 · Do I really need a grey card?

Future Man wrote:
I just wiggle the WB slider in Lightroom and don't think about this shit when I'm shooting.

(JOKE post... but yea, it's actually what I do now... Maybe when real color accuracy matters I'll start using a grey card)
You may be joking, but I rarely want a clinically correct white balance. Look at movies. The WB can be all over the place according to what look the director is after. Silent films were often tinted to convey a feeling or emotion.

Oct 20, 2009 at 11:57 PM

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p.2 #4 · Do I really need a grey card?

dmacmillan wrote:
You may be joking, but I rarely want a clinically correct white balance.

I totally agree with you, but I also find that it's easier to get the look I want starting from an accurate white balance than with one that's arbitrarily-set.

Oct 21, 2009 at 12:24 AM

Future Man
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p.2 #5 · Do I really need a grey card?

This forum is like a free education. Blows my mind. The internet ROCKS.

Oct 21, 2009 at 03:43 PM

dmacmillan
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p.2 #6 · Do I really need a grey card?

shatterkiss wrote:
I totally agree with you, but I also find that it's easier to get the look I want starting from an accurate white balance than with one that's arbitrarily-set.
I agree with you there.

Oct 21, 2009 at 05:00 PM

Carmen Miranda
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p.2 #7 · Do I really need a grey card?

cgardner wrote: first fill for the shadows, then add key on top of fill until just below clipping.

Chuck,

Not to take this sideways, but I'm a bit confused about your comment.
How do you fill shadows if the key has not been established and shadows created?

Oct 21, 2009 at 05:14 PM

cgardner
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p.2 #8 · Do I really need a grey card?

Carmen Miranda wrote:
cgardner wrote: first fill for the shadows, then add key on top of fill until just below clipping.

Chuck,

Not to take this sideways, but I'm a bit confused about your comment.
How do you fill shadows if the key has not been established and shadows created?

The key light doesn't "create" shadows. The shadows are already there courtesy of whatever ambient light there is before the key light is ever turned on. What the key light does actually is create a highlight pattern over the fill.

It might seem like a word game, but is goes to the core of the cause and effect of how fill and key light must work together to fit the range of a scene to the sensor to record detail over the entire tonal scale.

The reason any additional fill above ambient is needed is because the contrast range exceeds the range of the sensor.

Take a subject in put their back to the sun. Its possible to perfectly expose the shaded face lit by the sky with just the ambient light but the background which is 3 stops brighter will get blown out because the range of the sensor is only about 7 stops with detail. If we expose to retain the highlights, the camera sensor renders the midtones too dark (i.e., darker than seen by eye) and shadow detail is lost. Why? The scene range exceeds the sensor's.

No fill is typically needed on an overcast day and the lighting looks flat in a photo because the contrast of the scene lit with the even wrap around effect of the sky fits or is even shorter than the range of the camera. Same root cause: scene range doesn't fit the sensor.

Now lets consider what actually happens in sunlight when the sun is put to the back of the subject and a flash is used on the front of the face. It is commonly referred to as "fill flash" because it adds light to the shaded side, but what actually happens is the flash creates a highlight pattern on the front shaded side of the face. That is what a "key" light does. The places where flash doesn't hit and create highlights will still be shaded, but filled by the ambient light from the sky the person is facing.

Consider a totally dark room indoors. If you take a spot light and shine it on the wall, does the light create a room full of shadows or a highlight on the wall?

When we start with a totally dark indoor room and a light over the camera and raise its intensity until the camera sensor can record detail in the darkest parts what is happening isn't the creation of shadows, it is the creation of SHADOW DETAIL. The key light will overlap whatever detail is revealed in the shadows by a neutral fill light, creating highlights over top of the fill. Exposure -- with detail everywhere on the tonal scale of the scene -- becomes a total no brainer: just keep adding key light until clipping occurs in the textured highlights, then back off until detail is retained.

If you set lights in reverse, starting with only a key light and adding fill, as the fill level increases the exposure in the highlights will keep changing because what is actually happening, even though the fill is added second, is that the key light overlaps the fill. So you'll add a bit more fill, adjust the exposure, add more fill, adjust the exposure like a game of cat and mouse.

When fill is placed off axis it creates shadows. Where there are fill shadows there is an absence of fill and a dark void in the lighting pattern which I find harsh and unflattering on a face. YMMV.

If you can't visualize this word picture then just grab a couple lights, find a dark room, and try setting the lights both ways (key first vs fill first) and you will immediate grasp the cause and effect I describe.

Chuck

Oct 21, 2009 at 07:54 PM

Carmen Miranda
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p.2 #9 · Do I really need a grey card?

cgardner wrote:
The key light doesn't "create" shadows. The shadows are already there courtesy of whatever ambient light there is before the key light is ever turned on. What the key light does actually is simply create a highlight pattern over the fill.

It might seem like a word game, but is goes to the core of the cause and effect of how fill and key light must work together ....

I guess everybody has a different way of managing light, but this sounds a bit like counting sheeps hooves and dividing by four to get a count. Whatever works, works, I suppose, but I prefer to keep things simpler where fill is subservient to my primary (key) light source, whether it be ambient, back, side, up, down, continuous, flash or mixed. I find it much easier to visualize and work with my dominant light sources first, then regulate fill to refine the light balance to get a desired result. Only when fill cannot practically be regulated, as in the case of ambient sunlight, will I use fill as my base line for set up. Even then, I will have previsualized my key light, both in terms of level and position. In either case, the key, not the fill, will be the dominant influence and the primary determinant factor in my lighting strategy. How dominant will depend on how much fill is used.

Good luck.

Oct 21, 2009 at 08:59 PM

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p.2 #10 · Do I really need a grey card?

Carmen Miranda wrote:
cgardner wrote:
The key light doesn't "create" shadows. The shadows are already there courtesy of whatever ambient light there is before the key light is ever turned on. What the key light does actually is simply create a highlight pattern over the fill.

It might seem like a word game, but is goes to the core of the cause and effect of how fill and key light must work together ....

I guess everybody has a different way of managing light, but this sounds a bit like counting sheeps hooves and dividing by four to get a count. .

For old portrait guys, it makes perfect sense.

Back in the days when we just used a few thousand watts of tungsten bulbery for portraits, the first thing we did was to set the fill light and the fill exposure. A lot of older portrait photographers working with electronic flash still do it that way. That was because we shot negative film, and negative film is more vulnerable to losing image detail from underexposure of the shadows than from overexposure of the highlights.

So we set the exposure of the shadows--the fill exposure--as our base and then added light to that with the main light.

Chuck is saying that digital should be exposed with the same considerations--set the fill light first for an exposure that puts the shadows well above the noise floor where detail would be lost.

When Chuck says the main light does not create shadows, that's an interesting play on physical concepts. A shadow is a lack of light. You don't "create" a lack of light. You create light, and where there is no light, there is a lack of light.

Oct 21, 2009 at 09:50 PM

elusiv
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p.2 #11 · Do I really need a grey card?

cgardner wrote:
Carmen Miranda wrote:
cgardner wrote: first fill for the shadows, then add key on top of fill until just below clipping.

Chuck,

Not to take this sideways, but I'm a bit confused about your comment.
How do you fill shadows if the key has not been established and shadows created?

The key light doesn't "create" shadows. The shadows are already there courtesy of whatever ambient light there is before the key light is ever turned on. What the key light does actually is create a highlight pattern over the fill.

It might seem like a word game, but is goes to the core of the cause and effect of how fill and key light must work together to fit the range of a scene to the sensor to record detail over the entire tonal scale.

The reason any additional fill above ambient is needed is because the contrast range exceeds the range of the sensor.

Take a subject in put their back to the sun. Its possible to perfectly expose the shaded face lit by the sky with just the ambient light but the background which is 3 stops brighter will get blown out because the range of the sensor is only about 7 stops with detail. If we expose to retain the highlights, the camera sensor renders the midtones too dark (i.e., darker than seen by eye) and shadow detail is lost. Why? The scene range exceeds the sensor's.

No fill is typically needed on an overcast day and the lighting looks flat in a photo because the contrast of the scene lit with the even wrap around effect of the sky fits or is even shorter than the range of the camera. Same root cause: scene range doesn't fit the sensor.

Now lets consider what actually happens in sunlight when the sun is put to the back of the subject and a flash is used on the front of the face. It is commonly referred to as "fill flash" because it adds light to the shaded side, but what actually happens is the flash creates a highlight pattern on the front shaded side of the face. That is what a "key" light does. The places where flash doesn't hit and create highlights will still be shaded, but filled by the ambient light from the sky the person is facing.

Consider a totally dark room indoors. If you take a spot light and shine it on the wall, does the light create a room full of shadows or a highlight on the wall?

When we start with a totally dark indoor room and a light over the camera and raise its intensity until the camera sensor can record detail in the darkest parts what is happening isn't the creation of shadows, it is the creation of SHADOW DETAIL. The key light will overlap whatever detail is revealed in the shadows by a neutral fill light, creating highlights over top of the fill. Exposure -- with detail everywhere on the tonal scale of the scene -- becomes a total no brainer: just keep adding key light until clipping occurs in the textured highlights, then back off until detail is retained.

If you set lights in reverse, starting with only a key light and adding fill, as the fill level increases the exposure in the highlights will keep changing because what is actually happening, even though the fill is added second, is that the key light overlaps the fill. So you'll add a bit more fill, adjust the exposure, add more fill, adjust the exposure like a game of cat and mouse.

When fill is placed off axis it creates shadows. Where there are fill shadows there is an absence of fill and a dark void in the lighting pattern which I find harsh and unflattering on a face. YMMV.

If you can't visualize this word picture then just grab a couple lights, find a dark room, and try setting the lights both ways (key first vs fill first) and you will immediate grasp the cause and effect I describe.

Chuck

Chuck, you seriously deserve recognition for the amount of information you provide. The amount of effort you put into each post is nothing short of amazing!

Oct 22, 2009 at 01:44 AM

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p.2 #12 · Do I really need a grey card?

great conversation, now my head is about to explode.

Oct 22, 2009 at 02:38 AM

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p.2 #13 · Do I really need a grey card?

Carmen Miranda wrote:

Whatever works, works, I suppose, but I prefer to keep things simpler where fill is subservient to my primary (key) light source, whether it be ambient, back, side, up, down, continuous, flash or mixed.

I see fill as an equal partner. In fact in a 2:1 reflected ratio the key and fill are of equal INCIDENT strength:

H:S
1:1 Even fill on both sides of the face
1:0 Overlapping key light, same strength
===
2:1 Twice as much light reflects from the highlights vs shadows.

In all ratios the highlight tone is the same. Its the difference in tone and detail visible in the shadows which cause the brain to think light is "hard" or "soft". Conventional wisdom nowadays seems to be softness is controlled by the size and distance of the key light (i.e. wrapping the light around the object casting the shadow). But apparent softness can also be controlled with more or less fill.

Starting with fill and adjusting based on shadow detail s something the instant feedback of the camera makes possible. Its also the only way to visualize places the fill pattern isn't reaching. If you start with key and then add fill the unfilled gaps caused by shaded fill are more difficult to see. The most compelling reason is that it makes creating a file with detail everywhere on the tonal scale a no brainer.

You may think it makes little sense if you've never tried it, but if you actually try setting fill first I think you'll find it makes a great deal of sense, especially to someone starting out and trying to learn what the roles of key and fill are, and the ramifications of shaded fill.

Chuck

Oct 22, 2009 at 02:46 AM

Carmen Miranda
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p.2 #14 · Do I really need a grey card?

cgardner wrote:
You may think it makes little sense if you've never tried it, but if you actually try setting fill first I think you'll find it makes a great deal of sense, especially to someone starting out and trying to learn what the roles of key and fill are, and the ramifications of shaded fill.

Chuck

Thank you Dr. Fill for enlightening me.

Now I can move on to the next bardo plane.

Note to self: No wonder my kids never listen to me.

Oct 22, 2009 at 03:53 AM

cgardner
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p.2 #15 · Do I really need a grey card?

Carmen Miranda wrote:

Now I can move on to the next bardo plane.

Actually its my mission to enlighten people and help them understand how to use fill effectively before they depart the mortal coil

When you get reincarnated you need to learn stuff like lighting all over again. If you've been really bad in your past life all you get is a single light and a reflector..

Oct 22, 2009 at 01:26 PM

dmacmillan
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p.2 #16 · Do I really need a grey card?

RDKirk wrote:
Back in the days when we just used a few thousand watts of tungsten bulbery for portraits, the first thing we did was to set the fill light and the fill exposure.
For those of you younger than dirt, I feel the need to point out that this was one way, but certainly not the only way.

One of my lighting teachers at Art Center was Charlie Potts, who was director of the Photography Department at the time. He was from the old school, even worked with Edward Steichen during WWII in the Naval Photographic Institute. He and others taught us a different approach; setting your key and working from there.

It was an interesting time. We were doing portraits with hot lights shooting 4x5 B&W sheet film. I think you had to have been in the program a year before you could check out strobes. It was fun working with cine lights. We had some Juniors at our disposal, I don't recall if we had any Seniors. 5kw might be a little much! Of course, we had a number of Babys and Inka Dinks.

I need to dig out my Kodak binders. I have a couple, one with B&W films from the early '50's and the other a catalog of films from the mid '60's. There were a number of B&W portrait films available. As part of the specs, they all had H&D curve charts showing the curve in different developers. Some portrait photographers liked a long toe and gentle shoulder, some preferred shorter toe and longer straight line. A lot of old timers I knew liked a "full" negative. Blocking highlights didn't bother them too much, but they were deathly afraid of a thin negative.

Oct 22, 2009 at 02:03 PM

Carmen Miranda
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p.2 #17 · Do I really need a grey card?

cgardner wrote:If you've been really bad in your past life all you get is a single light and a reflector..

Dear Dr. Fill,

OK, I'll try to be good.
But thinking I should prepare for the worst, I reread your posts again and I'm still a bit perplexed.
I really want to get this right should I find myself in this predicament.
So how would I set my reflector for fill without setting my single key light first?

Regards,
Imso Confused

----------------------------------------------------
"It's what you learn after you know it all that counts."
John Wooden (a pretty decent coach, by all accounts)

Oct 22, 2009 at 02:39 PM

Carmen Miranda
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p.2 #18 · Do I really need a grey card?

PS. Can I stipulate that reflector as a Tri-Grip?

Oct 22, 2009 at 02:42 PM

dmacmillan
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p.2 #19 · Do I really need a grey card?

Carmen Miranda wrote:
PS. Can I stipulate that reflector as a Tri-Grip?

Can my single light be a north light?

I've got a ton of carte de visites and cabinet cards and I'm bowled over at the lovely light achieved with just a north light and flats (big reflectors).

One of my teachers, fashion photographer Tommy Mitchell, had a studio in LA and it had a huge north light window. You could partition sections off to control it. The window also continued halfway down the wall so you could somewhat control direction. Lovely, lovely light.

If I can't have a north light, give me a tri-grip and an old Photogenic "hog trough". Most photographers used the SkyLight as a big fill. If you turned it on edge to your subject, you could achieve a lovely wraparound light. Ratio was great for B&W and could be easily tamed with just a touch of reflector fill.

Oct 22, 2009 at 03:09 PM

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p.2 #20 · Do I really need a grey card?

I think I'm with the crazies in this thread. I hate having to think. I carry around a pack of white coffee filters in my bag. I stack 3 over my lens and set custom WB. Done and done... never out of a hundred K in temp when I bring it up in post. It's pretty much the same as ExpoDisc, except I'm a cheap ass.

In fact, I don't even know where my white balance card is anymore.

Oct 22, 2009 at 04:05 PM

cgardner
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p.2 #21 · Do I really need a grey card?

Dear Confused,

The answer to your question of course is that you can't set a fill LIGHT if you are not using a fill LIGHT.

But your question points out the dilemma with reflectors. The lack of independent control of the fill. Indoors it is nearly impossible to get a reflector where it where will catch and reflect the key light, where is will not create unfilled areas on a face, and not be in the photo. Its like winning the Trifecta at the Kentucky Derby.

Fill position is counter-intuitive which is why most beginners put it on the side opposite the key light and wind up with crossed-lighting with flat highlights and dark unfilled shadows. Fill needs to go in the places the camera sees and the camera shouldn't see shadows from the fill source. Where does fill not create shadows? When it comes from near the camera axis. Flat light may suck for just about everything else, but its the perfect direction for fill.

If someone learns lighting with one light and a reflector they may never, ever, see neutral fill. The way that some shadows of the face in the low areas are dark and harsh are accepted as the norm. But if one starts from a baseline of using two lights in a pattern of key light overlapping shadowless neutral fill where the shadows are even and the transitions buttery smooth, the potholes shaded fill creates in a lighting pattern are immediately obvious.

Outdoors a reflector is easier to use because outdoors there is light in all directions to reflect. In the most common outdoor portrait scenario, putting the subject's back to the sun and filling the front the reflector winds up pointing at the sun. That provides the needed light, but can also tend to blind the subject resulting is squinting. Use flash in the same situation and the same result can be obtained without the squinting

The ideal way to use reflectors indoors is to let neutral fill from the direction of the camera meet the technical criteria of lifting the shadow to the point the lame short range sensor can record detail, then use reflectors as need on the sides to nuance the shadow modeling on the sides of the face...

This image is copyrighted by the owner

It actually makes the reflector(s) easier to use because they don't need to do the heavy lifting of the shadows and can be aiming back and the fill light coming from the camera, or the key light source. In the case of the set-up used above both key and fill came from the direction of the camera.

The tools are less important than understanding what the tools need to do. Fill needs to reach everything the camera sees to be able to put detail in everything in the photo the camera takes. Simple as that. So whether using a just the sky, the sky plus a reflector, the sky + flash, or flash or a reflector indoors the question you need to ask yourself is:

IS THE FILL SOURCE DOING ITS JOB EFFECTIVELY?

Starting with fill first is suggested as the simplest and fastest way to learn what fill and key light do independently and together in a lighting pattern. Once its understood what the different roles are then its possible to tell when something isn't working as it should be.

When I look at a photo it takes me 1/2 sec. to know the fill is shaded just by looking at the nose. If the nose shadow is the darkest shadow on the face and is surrounded by bright cheeks the contrast will make it more distracting than if the nose shadow was the lightest shadow on the face. What makes a nose shadow darker than all the rest? When something, usually the cheek of long hair, has shaded the fill source (light or reflector) placed to far to the side of the face. There will also usually be harsh dark smile lines and teeth in the corners of the mouth shaded by the cheekbone. It doesn't matter if the fill came from a reflector or a softbox; either way it is simply not effectively placed fill if it creates dark unfilled voids in the lighting pattern, unless of course one likes harsh unfilled voids, or they are used intentionally to make the person in the the photo look tired, haggard, unattractive.

I'm starting to worry about you Mr. Confused. It seems the Karmic Wheel of Fortune has already sent you back with just the reflector, probably more than once. If you don't seek enlightenment this time around, next time you might be wagging a tail instead of holding a Tri-Grip reflector in one hand and shooting with the other.

Sincerely,
Dr. Fill

Oct 22, 2009 at 05:40 PM

Carmen Miranda
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p.2 #22 · Do I really need a grey card?

Oct 22, 2009 at 09:23 PM

Micky Bill
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p.2 #23 · Do I really need a grey card?

One light and a reflector? I 'd consider than enlightenment...

It worked for this guy.

http://tinyurl.com/yh4wpds

Oct 23, 2009 at 12:21 AM

cgardner
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p.2 #24 · Do I really need a grey card?

Who said a reflector doesn't work? Not I. I learned with a window and a reflector and I use them all the time. The ones in the shot above are 35 years old. But also use flash for fill when it does a more effective job. I'm not militantly stubborn when it comes to tools, refusing to use one or the other because of some belief its a "purer" form of lighting. I just work the problem and pick the tool that offers the best balance of results and convenience.

Its not about the tools, but learning to use them effectively. Like the gray card. It's a good tool for WB, and had a role in exposure for negatives when used with an averaging reflection meter, but its not an effective tool for judging digital highlight exposure. A reflector is very effective outdoors where there is light coming from all directions to bounce, less effective indoors when you need to choose between putting it where the fill is needed or where is can catch the light and be out of the way.

All I'm suggesting here is about fill is that its role be understood, and that the signs that it isn't working effective l be recognized: nose darkest shadow on the face, no light in smile lines and corners of the mouth, dark crescent shadow around the base of the nostril. Avoiding those things is just common sense: don't let the fill get shaded. Doesn't matter if the fill comes from the sky, a reflector or a flash, if its shaded its not doing its job.

As for your old photos Doug, in one of my photo books, "Portrait and the Camera" by Robert Lassam, the curator of the Fox Talbot Museum there is a photo of a large photo studio in the early 1900s. its basically a greenhouse with a glass ceiling and walls, with dark drapes hung over some of the windows to block the light and scrims over others to diffuse it. I don't see any artificial lights or any reflectors, just some clever use of subtractive lighting.

In any case fill wasn't needed with B&W because contrast could be controlled via the negative development to fit the range of the print. The first test I did with the zone system is put a person in direct sun and adjust exposure index and neg. development could reproduce the everything with detail, with no fill other than the light from the sky. There is actually lots of wonderful fill from the sky in a backlit shot. The problem now is that the dynamic range of a digital sensor isn't as long as that of a B&W neg. so it can't take full advantage of the fill.

Joe Zeltsman was a clever guy. He mounted his fill lights on the ceiling out of the way and bounced them off the back wall of his studio. Like in any lighting ratio his fill and his color negative exposures where a constant. The only thing that he had to vary was the strength of the overlapping key light, making the same incident strength for a 2:1 ratio, a stop stronger for 3:1, etc. Not sure if he used a reflector.

Chuck

Oct 23, 2009 at 02:00 AM

RDKirk
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p.2 #25 · Do I really need a grey card?

Micky Bill wrote:
One light and a reflector? I 'd consider than enlightenment...

It worked for this guy.

http://tinyurl.com/yh4wpds

Penn tended to use a very large, broad light with a more-or-less reflective environment.

What Chuck is saying about the misuses of sticking a smallish reflector next to the subject is true.

Oct 23, 2009 at 10:18 AM


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