2.13.2018

Thinking about the way I light my portraits and how to translate lighting built for large format cameras into lighting for small sensor cameras.


I liked the way I lit portraits in the time when big film allowed us to take maximum advantage of film's gorgeous highlight roll off. We could light right up to the edge of overexposure with black and white emulsion and especially with color negative film emulsions and have an almost certain expectation that we'd be able to manifest endless tones in even the brightest areas of our prints. When I shot 35mm transparency film I was a habitual user of a handheld, incident light meter so I could carefully match the light levels to a color zone system that occupied space in the logical part of my brain. The interim steps of either scanning or printing added a safety margin to our war against burnt highlights as well.

When we jumped across the chasm to digital capture it seems that the biggest casualty has always been the ability to retain great highlight detail without having to underexpose and then raise all the tones in order to compensate for our timidity. Until recently the method of underexposing in order to preserve valid highlight detail and tonality carried with it the curse of noisy and information poor shadow and lower mid-tone areas. There was also the very real disaster of banding in the shadows and mid-tone transitions that were the manifestation of lack of bit depth in the lower registers.

This was somewhat mitigated around 2014 when Sony sensors became more or less immune to the worst ravages of underexposure. Now that the technology of the shadow tolerant sensors have been implemented everywhere but in the Canon camp most of use are breathing a little sigh of relief. I have noticed though that m4:3 users are still closer to the edge in terms of highlight control versus overall dynamic range that we might want. Yes, the modern m4:3 cameras can do the same underexposure+lifted highlights trick as the cameras with bigger sensors but few are capable of shooting 14 bit raw files (perhaps only the GH5S...) and there is still some trade off between the overall information density of a camera like the Nikon D850 and the Panasonic GH5, in the realm of still photography.

Since I've cast my lot with the smaller sensor cameras I'm re-thinking how I light my portraits and I'm experimenting with ways to do so that don't depend on post production heroics or magic.

I'm more interested now in making light that's composed of smaller, closer lighting units. In the past I was a proponent of large light sources. I've often written about using 6x6 foot diffusion screens as main light sources as well as 72 inch diameter umbrellas, complete with diffusions socks over the front. Now I'm interested in using smaller soft boxes or, in the case of LED lighting, smaller diffusion flags, closer in toward my subjects and then using multiple sources to build an overall lighting design rather than just depending on big, soft sources and the necessary post partum enhancement.

Part of my investigation has to do with my increasing use of high quality LED panels in video settings. I'm re-learning how to sculpt faces better without imperiling my highlights or adding to much texture to faces that don't want to show off the daily battle scars of life.

In these undertakings it's good to remember that the inverse square law is your first assistant. Accelerating fall off is delicious, when used correctly.

I'm working on some examples of lighting that yield a tighter delineation of facial form and more interesting tonal transitions that I've used in the past. It's not enough just to get sufficient photons onto a subject; I'd like the photons, collectively, to also describe a more interesting range of information.

Just a few thoughts about lighting today. I've been watching too many Gordon Willis movies (a great DP). The lighting is just so much more interesting that most of mine. Now a conscious work in progress.

5 comments:

Frank Grygier said...

Yes. Can't wait to see it.

Craig said...

Kirk,

What you are investigating could make a very compelling e-book for your regular followers of The Visual Science Lab. I'd gladly pay the same price as what I paid for your LED Lighting book to learn more about how you achieve the wonderful lighting you employ in your portrait work.

Give it some thought - I bet you'd sell more copies than you might first expect, and it wouldn't necessarily require working with a book publisher (unless you're still under contract with one).

Regards,

Craig C.

Anonymous said...

This is the kind of thoughtful approach I like to come here for.
The endless chasing of tech specs to fit an existing workflow might key in neatly to GAS but your approach is the best way to improve the final picture. Can't wait to see the results,
Mark

Scott said...

I hate the gaudy red/yellow brand name on the manufacturers' straps, too. But I actually kind of like (some of) their ergonomics. Broad, thin and no oversized hardware.
And, I'm cheap.
And retired, so I have a lot of time.
Got some flat black acrylic paint from the art supply store and just painted over the logos.
Stealth straps for almost nothing.

Bill C said...

You so nicely sum up what I'm chasing 90% of the time as an amateur photographer who doesn't shoot often enough. That ability to "see" instinctively how the sensor (no matter the size) is going to interpret the light and the "shape" of that light remains one of my biggest limitations. Composition you can read about and practice and even pick up a little through absorbing the work of others. But light, you cannot take shortcuts there! Only hours of practice, experimentation, and frequent enough failure to truly learn from.