Speedlight flash diffusion test
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On camera flash photography has always challenged me. I learned photography, in West Germany during the early ‘70s, using natural light only, black and white film and developing my own prints. My first experience, in the early ‘80s, with a flash gun was a reunion of flight school classmates and our families. We paraded the kids through the living room, onesies, twosies, you know the drill, and I took whole family photos too. The garish, over exposed pictures with that damn hard edged shadow (like the top center picture) was embarrassing when the color prints arrived. Who needs a flash? Not a REAL photographer anyway. So, back to natural light for more than 2 decades.
Although I messed with studio lights for a while in the 90’s, I stayed away from on camera flashes. Now that I’m back doing studio work and portraits, lugging the Photogenics everywhere is a big pain. Most of the time, outside of the studio I just need fill light. The Nikon D-300 and SB-800’s allow me to use CLS and Commander Mode (off camera) but even that can be troublesome and, in a crowded area, a SB-800 may turn up missing. So, my old nemesis, the on camera flash came back.
This was just a quick test to see and study the effect of room light, pop-up flash, a naked SB-800, an Omni-Bounce OM-SB5, and an RS-DF100 FlexiDome Flash Diffuser. Also, direct and bounced flash with and without diffusers upon the human face. The one result of on-camera flash not reproduced by the manikin head (my daughter ran screaming from the house when I, yet again, asked her to let me “take just a couple of test pictures”) in this test is the “red eye” effect produced by flashing directly into the eyes before the retina can adjust. Ever see a photograph of the sweetest 2-year-old girl in the world with eyes of the devil? Think back to paragraph one.
The equipment and settings I used are listed below for those of you that care. Any combination of camera and flash should give similar results.
- Nikon D-300
- Nikon SB-800
- Lens = AF-S Zoom-Nikkor 28-70mm f/2.8 IF-ED
- WB = Auto
- ISO = 100
- Aperture Priority = f 5.6
- Focal Length 60mm
- Picture Control file = D2XMode1 (for me, this test was for light and shadow, not color rendition)(See my Picture Control File test here)
My test examples are straight-on head shots to see the effect of the flash and the resulting light and shadow on both the face and the background. It’s a straightforward test I thought I’d share which is educational (at least to me) and demonstrates the effect of the different flashes in a simple setting.
The setup:
- Camera about 4 feet from head
- Head about 4 inches from background
- Both the D-300 and SB-800 set to TTL mode
- The shadow on the far right edge in the top row, second photo is from the lens hood.
I had hoped for an “Aha, that’s the way I should always do it” picture. It did not happen. I expected the images would be useful, but until I placed them side-by-side I did not have a good understanding of the differences. PunkToad, the first commenter of the test photo strip on my Flickr Stream, summed it up best “They each have their own personality.” If I learned anything from this quick, non-scientific, flash test, it’s that each style of flashed light, like people, have their own use and personality. Just as you try to pick the right employee for a job or contractor for work around your house, you must understand the requirements of the job and choose the correct flash to meet the requirement and purpose of the task at hand.
Another commenter left this; “I bounce without diffusion at weddings 90 percent of the time… except… I never bounce straight up… usually over the shoulder to create 3/4 light…” He’s absolutely correct in pointing out that there is no one “correct” on camera flash technique.
Although I stated above that any camera and flash should give similar results, my equipment is not your equipment; you should do your own tests and experiments, get comfortable with how each change in flash position and/or diffuser used affects the personality of the photograph and your subject.
November 16, 2011 at 10:57 pm, Larry said:
Ray: Like you I have not used my speedlites in years. I either used my studio lighting with good softboxes or used available light with a reflector. I was interested to read your post because I have started to add some speedlite fill to my exterior shoots. After some trial and error I found as did Elmo that I still need to shoot manual mode for every thing from white balance to speed lite control. The results are not as “attractive” as when there is a good bounce from a reflector but when there is not enough contrast from a cloudy day then the added light has a purpose.
I am currently using a 430EX in slave mode, shooting through a 42″ Optic White umbrella and using my 580EX in master mode to control the slave. I would like to get a more directional and controlled light if anyone can suggest a different setup
November 17, 2011 at 5:47 pm, Alberto Oscarelli said:
you could buy a strip light soft box w/ grid. You get soft and directional light. something like this http://www.amazon.com/Fotodiox-softbox-Speedring-Eggcrate-2x2x1-5/dp/B0048WGKKK/ref=sr_1_6?ie=UTF8&qid=1321551873&sr=8-6 – To mount a flash you will need a ring adapter – The strip light narrows the light beam but you can always use a regular soft box too….it really depends on what you want to achieve
November 16, 2011 at 5:28 pm, Ohwoo69 said:
How can set ISO 100 in nikon D300?
November 17, 2011 at 5:43 pm, Alberto Oscarelli said:
Once you go past 200 u’ll start seeing LO -0.3, LO -0.7 and so on. That is how you go down to 100
November 16, 2011 at 4:35 pm, Dan S. said:
Wow. Nothing like a “educational” article wherein the author fundamentally misunderstands the point of the exercise, thus rendering it less than useful.
By shooting TTL, rather than selecting camera exposure and flash power manually, no two photographs are likely to utilize the same power/settings. Therefore, it’s practically useless to compare the effects of light modifiers on the subject and flash intensity.
Secondly, if you’re shooting event photography (which is about the only time I ever use an on-camera speedlight) invest the $50 in a quality flip frame and a sync cord. Raising the flash 5-6 inches above the hotshoe will eliminate a fair amount of the evils of on-camera flash. Some of my best event photography didn’t even use a fancy modifier — just a 3×5 index card and a rubber band, with the head pointed almost, but not quite, straight-up. (And I’m not talking weddings, or rinky-dink family events — these were formal, private meetings between senior U.S. government officials and international heads of state.)
November 17, 2011 at 9:10 pm, terms reader said:
I’ve done that, too, except I used my own promotional postcard (the back side of which was white) rather than an index card.
As for the article, it’s about the various ways to diffuse on-camera flashes. Light at different intensities doesn’t diffuse differently. Of course different power settings will be used, as different diffusion techniques at the same power settings will result in different exposures. Showing how the difference in exposure while using an OmniBounce and a FlexiDome is not the point of the exercise. Seeing how each one diffuses the light is the point.
November 18, 2011 at 8:40 pm, Dan S. said:
While I realize that the author was trying to illustrate the different diffusers’ effects, because he relied upon E-TTL, the exposures in each image vary dramatically, making it quite difficult to gauge the impact of the diffuser, versus the impact of increased/decreased illumination.
If the author had, first, gauged whether or not the OmniBounce needed an increase of 2/3ev, or the FlexDome a drop of -1ev, versus an unmodified flash bulb, he could have used manual modes on both the flash and camera, to eliminate the differences in exposure (and also, give himself a rough guide for flash exposure compensation when using E-TTL during a photographic event).
November 16, 2011 at 4:18 pm, Elmo Love said:
First of all, Auto white balance is metering for the color of ambient light, which DOES NOT match the flash. Second, if you want to know what your flash is doing, you need a MANUAL shutter duration quick enough to kill most or all of the ambient light.
Next, what color are the walls/ceiling that light is being bounced off??? See how the ETTL doesn’t evaluate the COLOR of the test flash??
The time exposure, white balance, and FLASH EXPOSURE are three SEPARATE calculations. In a sufficiently darkened room, with an ‘E-TTL’ flash, 1/100th, and 1/200th will yield THE EXACT SAME SHOT.
Strapping a diffuser on a camera/flash combo which you do not understand is not likely to fix much.
If anyone thinks I’m nitpicking, I’m not. Pointing out the correct spelling of “mannequin” is me nitpicking.
November 16, 2011 at 4:47 pm, Ray said:
Hello Elmo.
The test was conducted in normal usage test environment. If I’m photographing an event with an attached speedlight the event coordinator, venue management or host is not likely to turn off the lights so I can “sufficiently darkened (the) room”.
Most live events do not allow for fussing with settings for every shot. The E-TTL technology is just a tool but one with an amazing ability to correctly determine proper exposure on the fly. I conducted this experiment for myself to help me to better understand the way different on-camera flash modifiers affect the distribution of light.
The article never claimed to address the white balance – just the way the light fell and the resulting shadows. The ambient light was listed because it is important to the final image but again – the test was not about white balance.
You make many assumptions in your comment about my knowledge and ability. You should take the results of this test as presented or not – your choice.
Ray
November 18, 2011 at 10:19 am, Dwdallam said:
“The test was conducted in normal usage test environment. If I’m photographing an event with an attached speedlight the event coordinator, venue management or host is not likely to turn off the lights so I can “sufficiently darkened (the) room”.
Seriously, there is a lot of misinformation in these replies. Many of you should do some reading on how camera systems work.
For instance, you limit the amount of ambient light in a room (or outside) by using your shutter speed. So if you wanted your flash to do most of the illumination, you would simply set your shutter speed to a setting that reduces the ambient light where you want it. Now your camera senses that the room is dark, and gives the command to “make a correct exposure” as opposed to “‘fill the light.” Since shutter speed has no affect on flash exposure, you are free to use your aperture to affect as needed.
To help keep your shutter speed slower than 1/250th, you use ISO 100 (or whatever), again to reduce ambient light or an ND filter. The reason you might want to keep your shutter above 250th is because, although flash guns can sync at any shutter speed, the flash effective distance is reduced, and can be greatly diminished at high shutter speeds. However, this probably isn’t going to be a problem indoors where your subject to flash range is short anyway.
November 18, 2011 at 10:26 am, Dwdallam said:
Just wanted to clarify that when I said “shutter speed has no affect on flash exposure” what this means is that camera and flash combination will still try to get a correct exposure regardless of the shutter speed, when the flash being in ETTL. In the above example, you surely could use shutter priority mode and let the camera choose your aperture, but the preferred method is to use manual camera mode with the flash in ETTL. That way you can achieve the affect you want (reducing ambient light, or increasing it) while maintaining aperture control, and still getting a correct exposure.
November 18, 2011 at 10:09 am, Dwdallam said:
“First of all, Auto white balance is metering for the color of ambient light. . . .”
Wrong, at least for Canon systems. When a flash is used on camera, or with remotes and an on camera controller, and the camera is set to AWB, the WB will shift automatically to the color of the flash. “When the flash fires, the color temperature information is transmitted to the EOS digital camera. This feature optimizes the flash picture’s white balance. When set to AWB. . .it will work automatically (Canon 580EXII flash manual 49).
November 16, 2011 at 4:12 am, Ray said:
A link to a larger readable photo of the test:
http://www.flickr.com/photos/byrkdauph/2421347665/sizes/l/in/set-72157603903569410/