cgardner
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 Re: Strobist | |
ukphotographer wrote:
Because he wasn\'t a Luddite.....
In 1801 Joseph Marie Jacquard invented an automated loom which used punched card connected together is a belt to automatically. The Luddites were English textile artisans who protested against this automation often by destroying the mechanized looms.
The term \"Luddite\" became associated with anyone opposed to increased industrialization or new technology—like TTL control of flash. When I said \"But in my view Hobby was a Luddite in his slavish devotion to old manual flashes exclusively.\" it was because he preached against TTL as if it were a false religion.
Back when his name first was mentioned I Googled him and came across an audio interview with Hobby a Strobist fanboy had posted. In it Hobby kept repeating the work \"ethical\" to describe his a approach. Both he and the interview disparaged TTL metering, but from the ways they described it\'s many shortcomings it was obvious they hadn\'t actually used it, at least not enough to master it\'s use. In particular being Nikon users they weren\'t familiar with how the Canon system actually works, making erroneous references such as the AF assist lamp being the source of the woefully inadequate IR signaling.
I give Hobby credit where I think credit is due, but the main reason I became an advocate of the Canon system was to get the type of Canon owner I described — a hobbyist with a single 430ex in the hot shot wondering what to do next — \"deprogrammed\" from Hobby\'s brainwashing that manual and radio trigger was the ONLY way they could successfully move their flash off camera. I did that by creating tutorials they could read and consider before they threw their money at a problem they didn\'t understand based on the advice of someone opposed to the use of TTL for \"ethical\" reasons.
The fact Hobby used a camera with a higher sync speed than is normal today was the logical choice if one chooses also to only use manual flash and promote it as the only \"ethical\" way to do lighting. But most of the people following his advice weren\'t using camera\'s with 1/500th sync speeds and many new to flash might not even understand the difference unless it was explained to them.
If you take the trouble to read the my first Canon tutorial you will find it is an overview of the system that compares various approaches. Using the ST-E2 as a Master, using a 580ex as a Master, using manual radio triggers, and even forgetting about speedlights and purchasing studio lights instead.
Back before Radio Poppers going \"Stobist\" vs. using the Canon system (or Nikon\'s) meant taking the $300 430ex flash the hobbyist already at that point, spending $292.46 for a set of Pocket Wizards (what I paid for mine in 2005) and winding up with a single flash solution that moved the flash off axis, but without any fill.
Going further down the Strobist path and adding an eBay SB-28 or Vivitar 285HV for fill would require another set of PW would cost another $300 for the radios plus whatever the flashes cost (e.g. $75). So all in for a two flash lighting solution they would have spent:
$300 430ex
$75 used manual flash
$600 two sets of Pocket Wizards
$100 two stands @ $50 each.
$40 two umbrella holders @ $20 ea.
$40 two umbrellas at @ $20 ea.
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$1,115
At the time I bought mine 580ex flashes cost $380, so following the approach I used and suggested of putting the Master on a Stroboframe camera flip bracket (which still only costs $50) they would spend, assuming they had no flash gear and bought a pair of 580ex:
Single flash solution:
$380 580ex
$50 Off Camera TTL cord
$50 Stroboframe bracket
$5 DIY diffuser
====
$485
Adding second flash off camera:
$380 580ex
$50 One stand
$20 One umbrella holder
$5 DIY diffuser
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$455
Grand total for two flash Canon based solution: $940
Apart from the cost I explain the difference in logistics of wrangling two stands and needing to meter lights vs. roaming freely with a flash bracket and changing ratio and adjusting exposure with their index finger on the back of the Master flash above the camera.
I explain that in any static situation manual control is better than TTL and have a tutorial explaining how to set Manual ratios by distance without metering as I did for years with my Vivitars, a necessity with the Canon system because the pre-flashes affect a hand held meter reading. What makes that method work is the fact the fill is always the same distance as the camera allowing ratio to be set by the relative distances of camera and key light when key and fill are used at identical power. It is possible to also set ratio remotely in M mode but logistically its simpler to just move the Slave/key with the camera distance as in the \"good ol\' days\".
Addressing William\'s comment about using TTL at weddings.....
The system Zucker taught thousand of wedding shooters over the years was to use a ratio that perfectly fit the range of black suit > white dress to the print range. That happened to be 3:1 for color prints. To make a 3:1 ratio key light, overlapping fill, must be 2x brighter. (2:1:1 = 3:1) That can be done by using 2x more power, or by moving the light closer per the inverse-square law.
Monte was all about KISS and I can\'t recall the words \"Inverse-Square Law\" passing his lips, but he understood how to apply it. If shooting at 11ft moving the identical slave 8ft from the tip of the nose at a 45° angle made the key light 2x brighter and created short lighting on the the faces with normal \"seen by eye\" contrast with a full range of detail from the laces on the groom\'s shoes to the subtle difference between specular and solid whites on the lace and bead work of the brides dress. Moving to 8ft for a tighter crop you\'d move the key light to 6ft to maintain the ratio and close the aperture one stop to keep the exposure the same.
I still use the same technique with my Canon flash because it is a no-brainer and requires no metering. This Bridge screen shot is from a session where I arrived and shot portraits in M mode with my speedlight at a meeting of our church \"Lens Team\":
The first two frames are a shot to set Custom WB off the card and a verification shot. The third frame should be familiar to regulars. Before taking it I had set both 580ex flashes to M at 1/2 power and the camera at f/8. Using my arm span (5-1/2 feet) between nose and center of my DIY diffuser I set the distance for the slave. Then I stepped back to 8ft, the distance I find flattering for H&S shots, focused and fired.
The reason I use that shot so much is because it illustrates what happens when a lighting ratio creates a scene range which EXACTLY matches the sensor range. By coincidence the same 3:1 ratio that did that on a color print also does that on my camera. How did I discover that? By looking at the RAW image and the histogram in files which are rendered accurately in the highlights with solid white objects below clipping. I expose so the only clipping occurs in specular refection such as those off the metal rim of the glasses.
Being a technician and technical manager most of my working career I understand how the photographic process is engineered to work. When you manage the lighting so there is detail the shadows and the highlights at the same time, the DlogE response of the eye and the film and sensors engineered to mimic how we see is linear. The 45° line you see when you open an image in Curves. What linearity means in practical terms is that everything the camera records between solid black and specular white winds up looking \"normal\" per our seen in person perceptual baseline.
The histogram, if one knows how to interpret it relative to scene content will tell if the scene matches the sensor (full detail) or not (loss of detail on one or both ends). But to determine that one must first \"expose to the right\" exposing white objects just below clipping. Not necessarily to expose the photo that way, simply to evaluated scene vs. sensor range.
Indoors with flash fitting scene to sensor with manual flash is just a matter of starting with a foundation of even shadowless (as practical) fill to record detail in the shadows on the sensor. The quickest way to do that with a digital camera is turn on the fill only, take a shot then use your eyes and brain and evaluate the results you see. If you don\'t see any detail add more fill, the shadows are turning gray then reduce fill. With 1 or 2 test shot you\'ll have the shadows dialed in. Then you simply turn on the key light and adjust it until the solid white are just below clipping. The fastest way to do that is kept raising key light until clipping is seen in the RAW file then back off a bit. Once you test and get both ends right based on the RAW in the computer you look at the same file using the playback, histogram, and clipping warning on the camera, slap yourself on the forehead and say, \"So that\'s what a optimally exposed file looks like\"?
The advantage of Zucker\'s manual approach which I uses an pass forward it that once you determine how far to put the slave to fit foreground to sensor at various distances / apertures with the two lights, if you leave the two flashes at the same power with similar modifiers and shoot from those same distance/aperture combinations is practical to use manual exposure and get optimally exposed shots at the fly without metering. You simply need to be able to judge distance by eye (or paces) and adjust camera aperture as shooting distance changes.
That might seem to cramp one\'s style creatively, but with a constant aperture zoom lens like a 24-70mm 2.8 or 24-105 you could shoot just about every shot at a wedding with a few shooting distance / key light distance / aperture combinations with dual flash and all the shots will have a full range of detail on both bride and groom. You would of course be an idiot if you didn\'t chimp and check for clipping as you shoot, and to correct it you would simply adjust aperture +/- 1/3 to 2/3 stop to account for factors like \"spill fill\". As for how real world that is? I shot weddings every weekend for two years (the longest two years of my life) and have used that technique ever since successfully. What makes it work? The flash bracket. Putting the fill on the camera and systematically positioning the key light relative to shooting distance.
With color negative film the range the lighting had to fit wasn\'t the film\'s but the paper.
#2 B&W print paper had a 10 stop density range. That meant to make a print with black shadows and paper white specular highlights the negative, from clear base to highlight needed a density range of 10 x .30 or 3.0. With B&W film and the zone system would measure scene with a spot meter, determine the range, then adjust development so the highlights of the scene had a 3.0 density. The same scene on clear and overcast days would have different f/stop ranges and require different development times create the 3.0 highlights needed for the full range.
Why do I mention this? As background for understanding why flash became necessary outdoors. If there was enough ambient light brightness there was seldom a need for flash with B&W. Outdoors in direct sun you simply adjusted development time of the negative to fit the highlight density to the #2 paper range if using the zone system, or picked a grade of paper that fit the range of the negative with standard development.
What changed when color was introduced was the print range. The range of a color print is much shorter than B&W and unlike B&W the need to maintain color (gray) balance between the layers of the film didn\'t allow the film development to be changed to handle the range of a clear sunny day. Flash had been used outdoors with B&W but color film make using it necessary all the time.
The first type of photography to move to color was movies and the shorter range was one of the factors that moved movie production onto sound stages with elaborately constructed sets to shoot a horse opera rather than just shooting it outdoors because of the need for fill light to handle the contrast. Unlike stills movies need continuos light and a lot of it to balance the sun. It was easier to shoot in the studio and simulate the sun with rim light with a potted plant in front of it.
Color film forced still photographers to make Solomon-like decisions with every outdoor shot. Expose for the highlights and lose the shadows, expose for the shadow detail as they had with B&W or cut the baby in half, get the faces looking \"normal\" but blowing out the sky and losing the shadows.
The direction of the light became a more critical factor. For example here is a digital shot exposed for the white detail facing west at 11AM....
Here\'s the same exposure on the same subject, also exposed to keep the highlights below clipping but turned 180° facing east into the sun in the SE part of the sky...
The DR of the sensor is exactly the same for both so is the exposure criteria (highlight detail) so why does the first look \"normal\" and the second underexposed?
The difference is perceptional. What seems normal depends on what the brain thinks is most important. You know what a white towel and gray card look like by eye and the first one is a closer match so by comparison it looks \"normal\".
Without flash what would you do in the second situation? Most would adjust exposure until the foreground in the shade looked normal the way the eyes do when they focus on a backlit face or object. The brain ignores the fact the eyes are blowing out the highlights and shadows because it remembers seeing the overall scene as normal, more like the first shot.
That was an ETTL-II HSS test and I was shooting a f/2.8 in Av mode to see how what camera metering at the default EC=0 and FEC=0 would do and what was needed to correct it to get a full range of tone on the target in the foreground. To get the second backlit shot below clipping in the towel I had to dial in - 2 EC. The EC=0 shot was lighter and more normal looking overall, but my goal in the test was not to blow the sunny highlights with the ambient.
What is interesting to grasp in that test is that the TTL metering, left to find the best ambient only exposure for that scene on it own, would expose as I would without flash manually based on what I saw in the playback making faces and other midtones look \"normal\" despite knowing it would blow the highlights.
This is what I got when I reached up and turned on the 580ex, used direct, in HSS mode at FEC= 0:
The background is as underexposed as in the second ambient only shot, but the foreground just in range of the HSS mode flash 10ft away when measured separately with Levels has a fit range to sensor histogram...
While the test was done in HSS mode to test range, the more important knowledge I gained from that systematic test from the baseline of ambient only shots was how the ETTl-II metering that controls the flash works, and how to make it work predictable. The key factor it turned out was what I had been doing all along because I don\'t like blown highlights in my photos: start by controlling ambient and keep the highlights under clipping. The second key factor is something I also always do when shooting with flash KEEP THE SUN OFF THE FRONT SIDE THE FLASH HITS.
Both are common sense if you think about it. If you start with ambient clipping highlights — what TTL metering will do by default — it will look better before flash is added but after you add the flash to lift the shadows a bit more you\'ll wind up with a normal face and blown highlights where the sun hits. To get a normal looking face on the shaded side and not blow the highlights where the sun hits you need to start with the highlights below clipping. Then you need to avoid clipping them with flash by overlapping flash and sun by keeping sun off the front.
If you use the sun as \"key\" light to model the face then try to add flash to get rid of the dark shadows on the nose and eye sockets you can\'t add flash to the shadows without also adding it to the highlights. With normal non HSS flash you quickly hit the sync limit (e.g. 1/250th). If you start at f/11 @ 1/250th and have the cheek exposed perfectly with just the ambient, then start adding flash over the highlights you must start closing down the aperture more to prevent clipping.
Here\'s what happens numerically. Without flash the incident ratio of sunny 16 / shady 5.6 on cheek and nose shadow is 3 stops or 8x greater in the highlights 8:1
H:S
8:1 cheek:shaded eye sockets
What happens to the ratio when you add flash 1/4 the intensity of the sun (i.e. 2 units)?
H:S
8:1 cheek:shaded eye sockets (ambient)
2:2 fill flash 1/2 the intensity of the sun
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10:3 = 3.3:1
Adding flash is 1/2 the strength of the sun (i.e. 4 units) it hits both cheeks and shadows equally...
H:S
8:1 cheek:shaded eye sockets (ambient)
4:4 fill flash 1/2 the intensity of the sun
==
12:5 = 2.4 : 1
How lets stay you raise flash equal to the sun
H:S
8:1 cheek:shaded eye sockets (ambient)
8:8 fill flash 1/2 the intensity of the sun
==
16:9 1.7:1
or overpower it by 1 stop (i.e. 16 units)
H:S
8:1 cheek:shaded eye sockets (ambient)
16:16 fill flash 1/2 the intensity of the sun
==
24:17 = 1.4:1
The more flash power you add with a single fill flash the more it overpowers the ambient and lowers the net lighting ratio. By the time you add enough flash into the eye sockets and nose shadow to make them look \"normal\" the over look of the face is flat because most of the natural modeling has been cancelled. More importantly the eye sockets starting shaded and darker than the cheeks will still always be darker than the cheeks and forehead no matter how much flash you add, if it overlaps both. The eyes only look better and more normal because the flash add the sparkle of catchlights missing in an ambient only shot exposed for the sunny cheek.
That pretty much became the \"new normal\" for flash assisted color photography because the cause and effect wasn\'t clearly understood. I didn\'t understand it myself until I started experimenting and thinking about the results I was seeing and what was causing them. That in turn lead me towards techniques with solve the problem
The solution? Find ways to fit the scene to the sensor on the flash lit foreground AND make the results look natural. The clues how to do that are found back in the studio.
Putting back to the sun outdoors is exactly the same as using a hair light in the studio. Set it just below clipping where it hits, then in front of the face add even fill until the shadow detail is revealed, then overlap the key light until it is just below clipping....
Outdoors in backlight if you do the same thing, back to the sun, keeping the sunny highlights below clipping you get this...
Add one flash and it will adjust the exposure so it looks normal but kill the modeling of the natural light...
What is missing? The natural modeling. What created it? The angle the skylight hit the face. How to recreate it?
First pose the face into the skylight as if it were your \"key\" light. Skylight isn\'t \"Flat\" it is always downward and depending where the sun is in the sky in back one part of the sky can be brighter than the other. Clouds and haze will affect this so you just need to move the face around and observe to see the difference. Watch the both sides of the nose and eyes for the shadows and where they fall.
Then simply your second flash as key light at the same angle the skylight is hitting the face. For butterfly / full face aim nose directly into the natural light center the flash. For oblique / short light turn face 45° to the light and shoot into the shaded side, putting the flash at the same 45° angle relative to the nose...
The flash assisted lighting winds up looking \"normal\" because the key and fill flash allow the scene to match the sensor. The lighting winds up looking more natural than a single flash shot because the face is first pose to the natural light and flash is added at the same angles, complementing it, not fighting it.
That\'s a different approach than \"How can I overpower the sun with my flash\" and one that starts with knowing how to pose a face to the natural light in a flattering way. That\'s one of the reasons I also suggest photographer experiment and learn with a window and reflector first before throwing money at a problem they don\'t understand.
As for ETTL vs. Manual?
What I came to realize about digital sensor range vary and only one lighting ratio fits range to sensor perfectly. That\'s true of manually set ratios regardless of whether you choose to set them with a meter or by examining what the sensor actually recorded as I have concluded is faster and easier. The same is true of ETTL ratios. Only one A:B ratio will fit scene to sensor for any given scene.
When looking at this shot with a 3:1 ratio set by distance it looks unremarkable and uncreative but accurately captures what he normally looks like.
How does this shot look different in terms of \"hard\" and \"soft\" light and why?
It is the same file as above with a middle slider tweek in Levels. After working for Zucker learning to light faces in photos I spend the next four working in the photo labs at National Geographic reproducing photos and adjusting them for optimal reproduction when printer. That\'s how I discover how to manipulate PERCEPTION of a tonal range by shifting around the tones between the shadows and highlights the camera records. A middle slider correction in levels to the left does not change the DR of the shot, it just changes the brain\'s perception of what is there.
Perception is also affected by context. The same photo will seem different perceptually depending what the eyes and brain calibrated to for comparison around the photo.
But something else I came to realize by shooting mostly candids, not studio work in the same room all the time is that a 3:1 ratio in big room will not look the same as a 3:1 in a small room where the key and fill are bouncing off ceiling and walls more. What difference does that make? With same incident readings there will be more fill because the light not hitting the subject directly will bounce creating a \"wrap around\" fill effect not seen in the larger space. That\'s where most of the \"wrap\" from big modifiers often comes from: the 50% of the light hitting everywhere but the subject.
The more I experimented with both my speed lights and studio lights the more came to realize that setting ratios with an incident meter while an effective way to precisely control the intensity of the lights didn\'t predict how the resulting ratio would look like perceptually on white and dark backgrounds, or with different amounts of bouncing, wrapping spill fill. For example a 3:1 ratio, set by meter looks \"normal\" on a dark background, but that same ratio looked too dark on a white one.
My approach changed from \"by the numbers\" to starting from a baseline of fitting range to sensor then adjusting perceptually based on camera feedback. The camera doesn\'t accurately depict what is in the RAW but by systematically testing and comparing one with the other I trained my brain to understand what was happening in the RAW by interpreting the playback, histogram, and clipping warning. Given those new tools I found the best ways to use them and in the process concluded the old tool — incident meter — wasn\'t really necessary for the way I control my workflow. When I did meter I would wind up adjusting perceptually due to all the variables the meter can\'t measure anyway so the metering was redundant.
I use the same baseline method with ETTL ratios. The day after I got my flashes I did this test series...
I find in most situations A:B = 1:2 fits scene to sensor. So when I shoot with ETTL I start with 1:2 and adjust FEC until highlights are correct. That fits scene to sensor, my definition of technically correct exposure because it uses the full DR of the camera. Then from the baseline of that \"normal\" looking full tonal range I decide whether to deviate from \"normal\" by changing the ratio. Making face shadows darker globally with less fill will result in loss of detail in dark clothing. Making shadows lighter globally with more fill will make the shadows gray not black affecting the overall tonal range.
What Photoshop allows me to do is shoot \"normal\" for a full tonal then selectively adjust tones in the middle in the same way I dodged and burned prints in the darkroom. But instead of using the dodge and burn tools in PS I use adjustment layers as shown in this tutorial:
http:/photo.nova.org/AdjustmentLayers/ and other method locally in specific areas of the photo, not just globally with the tools like Levels or Curves.
Using that approach I find ETTL ratios more convenient and use them most of the time. It\'s just a matter of keeping the highlights below clipping and everything else falls in to place more or less automatically at capture providing a file with detail everywhere I can adjust to match the result I pre-visualized at capture like I did 40 years ago with B&W and a darkroom.
There\'s more to my overall approach that is evident in the examples I post, but it\'s all explained on my web site for those interested enough to read the tutorials and grasp 100% of the way I do things 
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