Sunday, August 30, 2015

Faux Fish Eye: Wrong Body, Right Lens

ISO 800, 1/25, F 8.0
Hurry, hurry, hurry. I was late for a swearing in ceremony of some new American Citizens at the San Bruno Public Library. I quickly grabbed a camera body from my bag and attached my 11-16mm DX format Tokina wide angle lens. I set the camera to ISO to 800, and made a quick sample shot to see how if I needed to change the ISO setting. I was stunned when I saw the clipped corners of the image. I took a while to realize that I had put a DX (a.k.a. APS format) lens on my full frame  D600 body. The Tokina wasn't designed for use with the larger format, so the physical edge created by the lens was clearly visible. I did manage to re-install the lens onto my D7000 body, and put my favorite 24-70 2.8 on the D600.

David Hobby blogged about using one particular APS lenses on a full-frame body. While his experience should have been identical to mine, he did point out the Nikon's APS 1.8 35mm lens would barely cover the full frame sensor when used wide open. Certainly the situation would be aggravated as soon as the lens was stopped down, but wide open and a centrally located subject, the sharpness of the lens could be fully utilized. I was unable to locate Mr. Hobby's  original post, but his use of this unusual lens/body combination is documented in his "Lighting In Layers" DVD set. The blog image created by this apparent miss-match can be seen here.

Nice Recovery! To illustrate the point, I simulated the limited area covered by the APS-sized sensor on the full-frame exposure. This approximates what the photo I would have made had I mounted the lens on my D7000 with its appropriate sensor.

Based on a liberal interpretation of the word "acceptable", this image could have been submitted on its technical merit. It's reasonably sharp and properly exposed, and assuming that the word "Return" was the center of attention, properly focused on the areas of greatest importance. It all reinforces a photographic truism: a technically marginal photo of a critical moment is better than a technically excellent photo that doesn't illicit viewer interest.

This is the photo I finally submitted. I thought it spoke to the importance of earning one's citizenship, and the flag in the lapel leaves no doubt as to where this new citizen's loyalties lie. It was never published.

That Kiss Of Light

"Kiss of Light" is a (Joe)  McNally-ism. Simply stated, it's light that doesn't dominate the image, gently supports the existing light. It should not cast a shadow of its own.

This photo was a cull* from a series of photographs from the Obon festival I made here in San Mateo.These shots, made in open shade, weren't worth considering for publication. However, when discussing exposure problems with a former student who was also there, I used some of these images to illustrate some potential exposure problems. I liked this particular shot well enough to make it the subject of this brief post. Two of these shots were labeled to be simplify identification in an e-mail message.

Open Shade: Besides a bluish tint. This can normally be corrected by selecting the cameras Open Shade white balance preset. Open shade also tends to be flat lighting with no sharp-edged shadows.

Imagine, if you will, an environment where light is coming from the left and right sides, as well as from above.  I was standing in front of a large building when I made this photo. This prevented any skylight from landing on the front of my subject's face. You can see that the cheeks and the forehead are lit, but the region below the chin, the eyes, and the teeth are not.

Front Light: This shot, also made at 1/1000 of a second, F 4.0, and at ISO 800, had a full blast from an shoe-mounted SB-900 speedlight. Just so that you know, the D7000 body was set to allow High Speed Flash Synchronization, so I wasn't limited to the normal ceiling of 1/250 of a second. The flash output was set manually because I couldn't rely on the camera's ability to properly render an image when the foreground subject occupied such a small percent of the total image area, as it did here. At full power, all existing facial shadows are essentially obliterated, and any sense of three- dimensionality removed from my subject's face.

Low Output Fill: The lead shot was made with the flash power turned to a much lower output level. A couple of  things are happening here. First, the flash now serves as a "fill" light, putting light in the subject's eyes, teeth, and neck. Second, the flash, which normally produces the equivalent of a Daylight white balance preset, is warmer when compared to the camera's Open Shade setting. This warm wash of light, when added to the cooler ambient lighting, gives the subject a healthier glow. And third, the flash introduces "catchlights", or glare spots, on any reflective surfaces.

How Much Is Too Much? During this experiment, I dialed the power up and down, chimping all the while, until I got something that I liked. I did not record my settings, so I would have to repeat the process if the distance between my camera and my subjects changed significantly.

Fill Light: By definition, Fill Light brightens the shadows, but does not eliminate them. We can see the details in the neck, along with the proverbial sparkle in my subject's eyes. Notice that when using the flash fill close to the lens axis, the catchlight will always appear at the point closest to the camera.The catchlights might seem a little low in this photo, but if you think of the eye as the reflective sphere that it actually is, the position is exactly where you'd expect them. Then too, humans are "hard wired" to assume that light comes from above, like sunlight. These low catchlights just aren't right.

I can't explain why there's a catchlight on my subject's teeth. I suppose I could have cloned it out in Photoshop, but I didn't bother for these samples. I do hope that this illustrates how a small "kiss of light" can add a little sparkle to an otherwise flat, open shade image.

*There are a number of reasons why the lead image wasn't considered for submission. First, the composition doesn't include the drummer's left hand, and cuts off the tips of the drum sticks. The subject is positioned in front of a background that is much brighter than the foreground/subject, which tends to draw the viewer's eye away from the main subject. And last, the image really isn't that compelling.

Sunday, August 23, 2015

Selens Tri- Flash Outdoors

Silhouetted against the morning sky on a bright San Anselmo Saturday is one answer to "flash on the cheap", a personal pursuit that dates back to the early 1970's. At the time, studio strength flashes were just not in my game plan, and the best I could do was to combine several inexpensive battery powered flashes in a desperate attempt to get enough light to photograph large subjects, like people standing up. My collection of small flashes included a Vivitar 180 and several Spiralite Seniors.Somewhere along the way I bought some optical slaves, and with a little ingenuity, managed to get them all to fire simultaneously.

Fast forward to 2015, when I purchased three Selens 3 in 1 Hotshoe Flash Brackets (SE-31) online. When I first saw it, I was drawn to the fact that it combined three hot-shoes that could be triggered through a 3.5 mm mini jack. This happened to be the same cable used by the MPEX Translator. And by assembling some bits and pieces, I could trigger the flash using a single optical slave. 

I gathered up three Nikon-safe Vivitar 285 HV flashes. Each was personally tested to have a triggering voltage less than 10 volts. If I could trigger the three with a single optical slave, I wouldn't have to worry about frying the electronics in my camera. But if I couldn't, I knew that the low triggering voltage would be "safe" to use.

You can see that I needed both a microphone-to-PC adapter and a Wein male/male adapter before I could attach the Wein Peanut. As it turned out, the combination wouldn't trigger reliably in bright sunlight, so I wound up using the a long mini-microphone cable to connect the Selens to an on-camera MPEX Translator. This triggered the flashes consistently, so long as I was careful to not trip over the microphone cable.

Nikon D70: 1/500, F22, ISO 200
I finally got around to making a photo, and was pleased with the the amount of light my three little Vivitars produced when fired in unison. As you can see, there plenty of power to allow for a darkened sky and "inky shadows". All this at a flash to subject distance of about ten feet. You'll notice that there are three distinct reflections in my glasses, something I didn't expect. 

I never thought that I looked like Popeye, although we so share a love of spinach. My exaggerated lower jaw comes from the camera's low position and wide angle lens. And while the flash-to-subject distance was ten feet, the camera-to-subject distance was only two. The joys of off-camera flash!

Why all this trouble? Well, I now have approximately 200 watt-seconds of power, just short of the output of a Norman 200b, with a replacement cost of less than $200.00. This "kit", along with some seldom-used Cokin 3-stop ND filter, a P sized holder and an assortment of adapter rings, will probably be added to my "just for fun" weekend only camera stuff that rides in the trunk of my car. The little flashes have neither the fast recycle time of the Norman nor the stamina for a long day of shooting, but will do in a pinch if both my subject and I are patient.

Photo Flop: I tried for about 20 minutes to produce shot where the three flashes were actually firing. I dropped each flashes output down to 1/16th power, the lowest manual setting available. I placed two speedlights behind a shoot-through umbrella to provide some front lighting, but it wasn't enough. What was worse, or surprising, was the light "smear" I got from each flash. I've never seen anything like this. Perhaps this is an artifact from using a camera as old as the D70. 

Lightbulb! I may attempt to re-shoot this photo with a neutral density filter on each of the flash heads. This would cut the output, and reduce the smearing effect.


Sunday, August 16, 2015

Think Tank Skin Strobe V2.0
Cool Stuff. Everybody seems to be interested in Cool Stuff. My problem is my tendency to buy an item before I know how I'm going to use it. Case in point is the Think Tank Skin  Strobe V2.0, a belt bag designed to carry a full-sized speedlight like the Nikon SB-900/910. There is a main compartment big enough to hold a speedlight with a diffusion dome attached. There is a second side compartment that can hold one (or two!) SD-8a Battery Packs if you remove their cases. A third zippered slit in the cover can accommodate some color correction gels.

So What's In My Bag? The preamble will give you an idea of exactly what I'll be storing in my Skin Strobe. Here's the deal. More and more, I'm relying on a supplementary battery pack to insure faster recycle times when working in high output situations. This bag allows me to attach the battery pack to the speedlignt and store them together. This setup will also allow me to keep the speedlght outside of my main bag.
Photo #1

The impetus for assembling this kit came from a recent near-accident. I was using a D7000 with an SB-900 mounted in the shoe. I was making lots and lots of ceiling bounce shots, so I attached an SD-8a to the speedlight for some extra juice, which I stored in my pocket. I had just finished a group shot, and went forward to re-arrange my subjects for a second pose. I put down the camera but forgot about the cable connected to the speedlignt. When I turned, the camera was pulled off the table and fell, back first, onto the carpeted restaurant floor. Luckily for me, no apparent damage was sustained.

It's my hope that having a place to store the speedlight / battery pack combination will prevent a repetition of the incident.

The photo at the left shows my solution for keeping the SD-8 battery pack in the side pocket, which isn't deep enough to completely contain it (Photo #1). However, the top of this side pocket can be velcro-ed shut, much like a zip lock freezer bag. The outside of the pocket is covered to "pile" (the Velcro "fuzz") which engages the Velcro "hooks" on the inside of the bag's cover. By using a 3" piece of double backed Velcro (see the down arrow), I could now keep the battery pack securely in place. A small stitch of cloth-backed "hook" tape (see the left arrow) is used to cover the tip of improvised retaining strap, and prevents the cover from pulling the retaining strap free.
Photo #2

It isn't hard to figure this out when the bag is in front of you. Trying to describe the setup without an overabundance of adjectives is more of a challenge then I'm willing to undertake at this time.

I filled a 12-battery box with AA batteries, and pushed it to the bottom of the main compartment (Photo #2). This keeps a fresh set of batteries at the ready while raising the speedlight high enough to prevent the synchronization and power cables for being "bent". You can tell that the unit is inserted "nose first" so the hot shoe is at the top. Just remember to orient the battery box to its lowest possible profile.

I'll add an update to this post after I've had some time to actually use this setup. But so far, it seems like a the bag will work out fine.

Sunday, August 9, 2015

Oh Wall, Oh Sweet, Oh Lovely Wall!*

Warning: Much of what is done in with speedlights in the field is only made possible by the instant preview feature available with digital cameras. There will be exposure adjustments made on the fly, resulting in some unexpected and disappointing first tries.  iTTL will get you to third base. With some fine tuning, you'll score a home run.

When I'm on assignment, I generally try to make two photos with two different viewpoints: A visually interesting shot for possible placement on the front page, and one with lots of local participants for the Community section on Page 18. For the former, I usually follow the old rule of the Four B's: Babes, Babies, Beasts, or Blood. Include one or more in a photo and you have it made.

I was at the Obon festival in the Buddhist Temple here in San Mateo, hoping to find an interesting shot that might make page 18, or with some luck, the front page. In the first shot, I found two sister dressed in beautiful kimonos. After introducing myself to their mother, I had to decide where to place them. You see, the Buddhist Temple courtyard has walls on three sides, so the prevailing light would be high overhead blue sky. However, since it was late in the afternoon, one white west-facing wall was acting like a giant reflector, so I positioned my subjects in front of this convenient, soft, light source. 

ISO 640, 1/2500, F 2.8
It took three shots to coax a smile from the younger sister, but the results, minus the fellow in the background, made for a nice shot. Incidentally, if you look closely at the fans, you'll find them slightly out of focus. Blame that on too much "shallow depth of field" enthusiasm!

ISO 800, 1/800 @ F 2.8
Ambient Light With Fill: It was twilight when the Bon-Odori, the dance done at the conclusion of the ceremony, started. I decided to use the wall behind me as  a bounce surface for a shoe-mounted SB-900 with a converted SD-8 battery pack attached for additional juice, as a lot of power (light) is diverted when bounce flash is used, especially outdoors. And when using High Speed Sync (HSS), there's even less. There was just enough light to add some twinkle in my subject's eyes, but not much else.

1/320, F 2.8, ISO 800
As the ambient light began to fall, I increased my exposure time. Same flash fill as before. When compared to the previous shot, you can see that the lighting is less directional because the ambient had dropped to a level  closer to that of the frontal flash fill. Remember that when using HSS, the rules on exposure aren't the same as those with conventional flash. While I had increased the ambient by a factor of slightly more than (1 1/3 stops), the longer exposure time actually increased the the flash output slightly. I doesn't make sense, so just trust me.

1/10, F 5.6, ISO 800
Dragging Shutter: The evening had grown darker still, and the decorative lanterns were finally lit. Since my shutter speed had dropped below the 1/200 of a second conventional flash sync ceiling, I was getting much more power from the shoe-mounted flash, so it behaved more like a key light and less like a fill. In a moment of whimsey I rotated the camera, giving me the arc-shaped streaks in place of the lanterns. It was a fun experiment, but I'm not sure I'd do it again, should these same circumstances present themselves in the future.
1/5, F 8.0, ISO 800
These shots are starting to get closer to what I had in mind. The darkened sky is now truly blue, and the background details are minimized by the decreased ambient. The lanterns look more like lanterns, and the overexposed windows and doorways in the background keeps the viewer within the courtyard. The wall bounce is now a very dominant key light, and in spite of the smaller (F 8.0) aperture, seems to provide enough light. I went with the small aperture for the increased depth of field, a concession necessary due to the difficulties my camera had finding focus in the waning light.
1/10, 5.6, ISO 800
I'm usually much more careful about "cutting off" my subject's feet, but it couldn't be helped. The shortest length on my zoom lens on my camera was 24mm, and it just wasn't quite wide enough. I find that wide lenses force me to get close to my subjects. But because of some obstacles behind me, I couldn't back up any farther.

1/10, 5.6, ISO 800

If your wondering why these photos a lacking in "eye contact" the reason is simple: They are dancing while walking in a circle, stopping only occasionally to turn around to face me. It seem that they were always facing towards camera right so they wouldn't trip, or facing the middle to get their instructions, so there a very few faces in these shots.

Lest you think there is some sort of magic afoot, all these images needed some post-production adjustment, but surprisingly, not much.

*Shakespeare, William. A Midsummer Night's Dream. Act 5, Scene 1