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Maury Registered: Jan 23, 2005 Total Posts: 111 Country: United States |
Has anyone tips (including, "Don't do it!") for taking pictures in direct sunlight? ![]() ![]() |
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Justin Berman Registered: Oct 17, 2006 Total Posts: 1446 Country: United States |
It depends on what you want to achieve. For family snaps your recipients likely wont care about the harsh shadowing. For fashion work, I would suggest overpowering the sun with on set lighting. You can also do shadow filling with an on camera speedlight, this can often be automatically configured by the camera to reduce overall scene contrast, making your family snaps just as easy as they were before. |
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cgardner Registered: Nov 18, 2002 Total Posts: 8543 Country: United States |
There are two factors to consider: how the direction of the light models the objects it hits, and how the contrast range of the lighting in the scene fits the range of your camera sensor... ![]() Put the camera on a tripod and frame the card in flat sunlight so it fills the entire viewfinder without any glare on the card. Set custom WB off the card so the RGB values will be the same in the file images (more or less). Put the camera in M mode, use your fastest lens, open it wide then find the shutter speed which overexposes the card to the point where it just barely clips in the playback warning. Then increase shutter speed by 1/3 stop so the card is just below clipping (i.e. eye dropper value of about 245). Then make a series of exposure by closing down the aperture 1-stop with each successive shot. As you cut exposure you'll see the spike the card creates on the histogram because there's only a narrow range of tones on the card march to the left on the horizontal axis. The red lines in the illustration above correspond to where the spikes were on my 20D histogram when I did the test. The little tone patches are cut/pasted from the file so show what tone the card was reproduced as. Its an 18% card, but it can reproduced as anything from white to black depending on how it is exposed. If you examine ordinary images you take with the eye-dropper tool you'll find that the point where you can discern the difference between 255 specular highlights and detail is about 245, which is why I use it as a starting benchmark for the test above. On the shadow end its difficult to perceive any significant detail in values under 30 in part because the digital capture process creates artificial noise in the shadows. Between 0 and 30 much of what you see is amplified noise. The higher the ISO the more its amplified and noticed. So the range in f/stops between where the card was reproduced at RGB values of 245 and 30 define the dynamic range WITH PERCEPTIBLE DETAIL the camera sensor can record. The test showed that my 20D has a range of about 6-2/3 stops with my 24-70mm f/2.8 lens.. The lens is a variable because each lens will have different contrast characteristics due to lens barrel reflections and other variables. A flat lit scene will have a range of about 10 stops on a clear sunny day. So that test of the sensor range tells me that if I exposed my file for detail in a brightly lit t-shirt I will lose about 3-1/3 stops of detail in the shadows. Exactly how much detail that is would require measuring the scene with a spot meter. Suffice to say things like shaded eye sockets will be very dark and lack detail. Even if you shoot on an overcast day the brow will shade the light from above and make the eyes darker than the cheeks. The only solution for that situation where the front of the face is oriented to the direction of the sun is to raise the chin of the subject into the light so it reaches the eyes. Fill flash in that situation won't help because it will hit both the shadows and the highlights. When flash overlaps the ambient highlights and you add flash it doesn't reduce the contrast between highlight and shadows (the crux of the problem) As you add more flash you'd need to increase shutter speed to cut the ambient, which will just make everything darker, highlights and shadows. This gets us back to creating the illusion of 3D. If you turn the subject so the light is at there back their overall form will have a greater illusion of 3D than if flat lit, but their face will be in light which is about 3 stops darker than the highlights on the shoulder of the white t-shirt where the sun hits directly. If you expose to keep detail in the shirt the face winds up looking very dark in the photo because your camera range is so short. Three stops from the highlights will fall somewhere around the middle of the histogram. The solution is to add fill to lift the shadows. The reason adding fill will work with backlit subject is because the fill you add will not overlap and lift the ambient light if the subject is positioned to the ambient so no direct sun hits the face or head. As you add flash fill the shadow side gets lighter but the sun-lit side remains unchanged. Some areas where the rim light is visible to the camera may get blown, but that will seem natural perceptually. By virtue of being able to independently control the light level on the front of the subject separately what happens is that on the front of the subject the contrast range of the scene is reduced to match the range of the sensor. That allows the sensor to record detail EVERYWHERE in the foreground. The background beyond the reach of the flash will still have a 3+ stop loss of shadow detail, but in a situation like a portrait a darker background is actually a good thing because it makes the normally lit foreground contrast more. The key factors when using fill flash are: 1) understanding that in backlight situations its really the key light raising it above the heads of the subjects for natural modeling; 2) understanding the role fill from the sky plays in a backlight scenario; 3) balancing the fill perceptually to the context of the scene. Natural light comes from overhead. It creates a downward pattern of highlights on top and shadows below the brain recognizes as "normal" 3D modeling of the face. When the light creating the modeling gets to eye level the lighting looks flat because there is no highlight/shadow contrast created. When the light creating the modeling drops below the eyes the highlight/shadow pattern becomes the reverse of natural light and looks weird and unnatural in a way which your brain will sub-consciously react to, but you might not consciously be able to understand if you are new to lighting (i.e. it doesn't look normal but you don't have a clue why). The reason is that the brain matches the contrast pattern of the image to its memory of what faces look like in natural downward lighting and the patterns don't match. These are the patterns which do match: ![]() When you use flash with stronger ambient back-light the flash isn't fill, its the key light for the foreground. The fill on the front of the face comes from God's own softbox, the northern sky north of the equator and the southern sky south of the equator. Remember that soft wrap around light is there, its just a bit to low in intensity for your lame ass camera sensor to use it effectively. The face will look too dark in just the ambient light, but when you use the fill flash -- raised over the head to create downward modeling on the facial features - it looks fine perceptually as the shadow values for the face in a full-face shot... ![]() That shot was take with a single flash on a bracket with my 9 x 12 DIY foam diffuser. I picked a light background - light bouncing off a river - to make the clothing non-distracting, used the raised flash to create the "mask" pattern of natural highlights (the bracket makes it pretty much a given and a no-brainer) and the the sky in the direction she was facing lifted the shadows on the front of the face, which complement the highlights the flash added on top of them. It works because the flash complements the natural lighting instead of trying to fight and overpower it. The other shot in the blurred mask example was taken with two direct, undiffused flashes to illustrate how much soft fill the sky will add if you use natural light wisely... ![]() Getting just the front of the face highlighted in an oblique pose (i.e., short lighting) is a variation of "shoot into the shadow side" which I think reveals a face in the most natural and flattering way possible because the angle to the camera reveals the shape of the cheekbone with a nice compound curve from eye to chin, and the the lighting from the far side makes the highlighted front of the brighter, tricking the brain into thinking the face is slimmer and more symmetrical that a flat lit full or oblique view would look. Getting that pattern is really easy. Put the off camera flash 45 degrees from the center of the nose, whichever way its pointing. Softness is also a perceptual illusion. Photons are neither hard or soft. Its how many direction the photons come from relative to the object which make the shadow edges distinct or fuzzy, but how dark or light the core "umbra" area of the shadow more than anything triggers the "soft" vs "hard" perception of the object the light hits. So to make the lighting look softer in the test shot with direct flash I added fill from the camera to the light placed 45 degrees from the nose on the right side. Again, both lights were direct flash, but all both were actually doing is lifting the wrap-around sky fill that was already there. Without any flash the face would be -3 stops below the light on the hair and shoulder in the sun. Perceptually I didn't want the flash to exactly match the sun lit parts. That's a recipe for flat lighting. So what I wanted was: 1) Sunlit highlights exposed just below clipping with ambient exposure 2) Highlights created with off camera flash about 1 stop below the sun highlights, similar to what would be seen by eye which adapts when looking at the face to make it seem brighter, but not as bright as the background ambient. 3) Fill on the shadows of the face with where about 1 stop below the highlights. So from the baseline of the ambient only face being 3 stops below the sunlit side: 1) Add 1 stop flash fill to the natural fill, which raises the shadows on the face 2 stops below ambient highlights 2) Overlap the -2 stop (from ambient fill) with + 1 stop of light from the flash on the right to make to create the H:S contrast on the face. So in that backlight + 2 direct flash lighting scenario the fill flash was only really lifting the shadows by 1 stop over natural and the off camera flash was only lifting the combined natural+ flash fill by one more stop. In that scenario the light bouncing off the sky did most of the heavy lifting. The flash just kicked it up a notch to the point where the camera could record it as it would be seen by our adaptive eye sight. Here's the shot without the test card (which tends to skew perception of the face lighting) not blacked out: ![]() So the points here are: 1) Understand the how light angle creates the illusion of 3D 2) Understand the range your camera can record with detail 3) Develop strategies to deal with the limitations of the camera's range such as shooting into the shadow side and using flash to lift the natural fill from the sky to reduce the contrast of the foreground to match the range the camera can record with detail. I keep a flash on a bracket with a diffuser when shooting outdoors. ![]() It is not the most convenient or comfortable thing to do when hiking to 11,500 ft. in the Rockies, but I feel the control of the contrast and lighting in outdoor situations makes it worth the effort. ![]() ![]() ![]() ![]() ![]() ![]() ![]() The problem shooting with flash in direct sun is the x-synch limit of 1/250th on most cameras which puts you at f/11 when shooting at ISO 100. The solution to that dilemma is to use a system flash like the 580ex which has high-speed mode. The pulsing mode cuts flash range, but that is compensated for by shooting at wide apertures, which reduces the the amount of flash power need. See this test I did with high speed flash. It explains the difference between technically correct exposure (i.e. don't blow the highlights) and what looks correct perceptually how average metering and human perception render it. http://super.nova.org/DPR/Canon/HighSpeedFP.pdf Chuck |
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Maury Registered: Jan 23, 2005 Total Posts: 111 Country: United States |
Justin: |
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Maury Registered: Jan 23, 2005 Total Posts: 111 Country: United States |
Chuck: |
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joewoo Registered: May 04, 2006 Total Posts: 593 Country: United States |
Ok.. So chuck.. It sounds like you're getting metered measurements and shooting with time on your side... Let's say I'm using straight ettl... Would I be wrong to shoot into the shadow side and use -1 flash exposure comp? That way the backlit subject would still look backlit? I understand that ettl is very dependant on composition.. But let's say the camera is set to center weighted and you have a model in the middle of frame (not off to the side) ... I guess what I'm saying is in a condition where the ettl measurements would be correct and not with some blinding light affecting its guess... I understand what I would do for realistic 3D look when I have time to meter... But not with ettl.. |
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joewoo Registered: May 04, 2006 Total Posts: 593 Country: United States |
Wait.. Forget the center weighted thing.. Let's say I'm in manual mode and I have my shutter at 250th and my f/ is so that the backlit highlights is just below the clipping point... Let's say I use ettl... sounds like I'd want to set it to -1 fec to make the subject look backlit and jus bring up the shadow side to the cameras range and let the viewer percieve it as normal |
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cgardner Registered: Nov 18, 2002 Total Posts: 8543 Country: United States |
Joe, ![]() The curve is kissing the right side. The three peaks were created, right-to-left, by the towel, the gray card, and the shadow if the towel on gray card. There's not much clipping in the shadows. Same type of target, with same exposure aim-point: adjusted to keep the white towel below clipping: ![]() The cross light creates more contrast than the flat lighting does and you can see the histogram piles up and runs off the left side indicating clipping in the shadows (no detail). This creates a dilemma. If the texture in the highlights of the towel (or white shirt if it was a portrait subject) is to be retained the face will be too dark. If the exposure is increased the whites will get blown. That example was taken at f/2.8 in Av mode and it required - 2 EC to keep the towel highlight from blowing. - 1 EC or even 0 EC would have made the foreground more normal but blown the highlights. If its a fashion shot you might go for the garment and let the face go dark using the - 2 EC. If its a portrait you'd need to get the face right at the expense of blowing the shirt and want to use -1 or 0 EC depending on how much in shadow you wanted the face to look. Here's what happened when I reached up and turned on the flash which was set to FEC=0 in ETTL mode: ![]() The metering interpreted the scene and added just enough fill to match foreground and background. In the original the area which is sun lit is a bit brighter than the flash filled part, but now blown. The histogram is still showing clipping, but its in the background. Here's the histogram of the foreground which shows it fits the sensor's range with no clipping on either end: ![]() So by having fill flash available for use when needed there's no need to make compromises or decisions about which end the the scene to clip. Until someone invents a sensor which can record a 12 or more stop range of detail the need for fill flash will be a fact of life. Chuck |
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joewoo Registered: May 04, 2006 Total Posts: 593 Country: United States |
ok i can see how theres a problem with exposing so the highlights are not clipped... i guess i wanted to know more about the relation of the fill flashed face vs backlight highlights... at what point does this fill flashed face LOOK flashed.. to me, the fill flashed towel looks flashed... i thought maybe its because theres a 1:1 (through ettl) relationship of the flash exposed front vs the backside highlights... i was thinking if i expose so my highlights dont clip, and i fill flash -1 fec... then the subjects face would look backlit, yet, decently exposed... i dont want to blast the shadow side of the face and then create a photo that doesnt look back lit like it originally was... is it purely preference? |
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c.d.embrey Registered: Aug 21, 2008 Total Posts: 1146 Country: United States |
Even the lowest priced DSLR, as noted by Justin Berman, is very smart! In fact smarter than most casual shooters. The following 3 photos were shot on automatic with a Canon 40D and the built in flash. ![]() ![]() ![]() The shots are well exposed, not even close to clipping the whites. The shadows are filled, but not over filled so they look natural. Even though I've made my living since the 1970s with photography, I don't let my camera get in the way of what I'm doing for fun! For snapshots I just set it on auto and let the camera do what it does best. You should too. |
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EA6B Registered: Mar 22, 2002 Total Posts: 5423 Country: United States |
I have a large round diffuser from Calumet. Works really well. |
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cgardner Registered: Nov 18, 2002 Total Posts: 8543 Country: United States |
joewoo wrote: |
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joewoo Registered: May 04, 2006 Total Posts: 593 Country: United States |
hmm i see... well thanks for the posts/info.. i can see how if i chimp and then adjust EC so theres no clipping works... but what about setting the camera to Av.. using spot meter (1ds II) set to +2 1/3 EC on the brightest spot in the frame.. exposure lock/recompose/shoot... this will meter the brightest area, tell me the exposure for middle grey, then adjust +2 1/3 so i dont clip (using ettl fill flash as well)... do people ever shoot this way? what is wrong with this method? |
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cgardner Registered: Nov 18, 2002 Total Posts: 8543 Country: United States |
joewoo: Spot metering is the way you suggest would also work. In fact I suggest it in one of may tutorials for changing the target value your hand-held spot meters. But you'd need to test to find the the correct offset value for your camera (it might not be 2-2/3). There is nothing right or wrong with any method if it produces the desired result, its a matter of personal choice in finding what for you is the best balance of convenience and results. I suggest the OEW method because I haven't found anything simpler yet |
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joewoo Registered: May 04, 2006 Total Posts: 593 Country: United States |
Thanks for the info/time |
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cgardner Registered: Nov 18, 2002 Total Posts: 8543 Country: United States |
joewoo wrote: |
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joewoo Registered: May 04, 2006 Total Posts: 593 Country: United States |
The "hardest" part of the wedding is during 2:30 pm... Which I will be outside in the direct sunlight if weather hates me... I work 6 days a week til and usually don't finish till about 6pm... I wish I could shoot during work.. But customers come at random times... The past couple sundays I've had was ruined with rainy days and food poisoning from ice cream...I kid u not! |
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anotherview Registered: Nov 02, 2008 Total Posts: 2287 Country: United States |
cgardner: Your words, how true: |
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c.d.embrey Registered: Aug 21, 2008 Total Posts: 1146 Country: United States |
joewoo wrote: ![]() Shooting Mode A-DEP Tv(Shutter Speed) 1/250 Av(Aperture value) 16.0 Exposure Compensation 0 ISO Speed 200 Focal Length 10.0mm White Balance 0 At 10.0mm I could reach out and touch him I'm so close. Once again, not maxed-out at all ! The following photo was shot indoors under florescent light with a Canon 580 EX mounted on a CB Mini RC Bracket http://www.custombrackets.com/scripts/prodViewnew.asp?idproduct=139 ![]() Shooting Mode Program AE Tv(Shutter Speed) 1/60 Av(Aperture value) 4.0 Exposure Compensation 0 ISO Speed 200 Focal Length 85.0mm White Balance Mode Auto This photo was shot from about four feet using a 580 EX and camera set to Program AE. Notice that his face balances to the background and looks natural. Also notice how camera dragged-the-shutter automatically to 1/60 to match background to foreground. And the 580 EX is deffinitly not maxed-out For many people shooting in either Auto or Program is a good option. When shooting the kids/grand kids, don't let the camera get in the way of you and them having a good time. |
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alanwarp Registered: Oct 09, 2007 Total Posts: 988 Country: United States |
Fill flash can help, see this thread: ![]() |