3.06.2018

Musing about last Saturday's photo assignment where the critical parameter (as usual) was the lighting.

This shot is here to illustrate what I write about in the blog below. 
It is not a "finished" "polished" portfolio piece. You didn't pay for that.
We'll fine tune and enhance the final image that the client chooses from 
this set up. We don't routinely polish everything that gushes out of the camera.
There's not enough time for that. But I think this illustrates a point 
I'm trying to make below.

GH5+Olympus 12-100mm f4.0 Pro.

Amy and I were on location by 9:00 a.m. on Saturday morning. We were shooting another radiology clinic in Austin, Texas. Our shot list was ample but that's par for most image catalog shoots these days. These kinds of assignments can be done with just about any good interchangeable lens camera made in the past few years, anything from 16 megapixels to 50 megapixels will work fine. And based on the metadata associated with the files the quality of the lenses you use is a lot more important that the advertising impressive fast apertures. Most of our shooting through the day was done with a wide ranging zoom and it was used almost exclusively at f4.0. That's not f1.4, that's f4.0.

But the unforgiving piece in every scene is the lighting. Nearly every room we worked in had a combination of fluorescent lights, each with their own unique color characteristics and light properties. The long, ceiling mounted tubes gave off a softer, greener light, with a mix of blue. The compact fluorescent bulbs in the recessed ceiling cans had a deep yellow cast to them. Mix them together and you've got a real Rubik's cube of a color puzzle to solve.

The worst set of problems come when you need to photograph a scene like the one above in which you are showcasing an MRI machine. An MRI creates a very, very powerful magnetic field which requires the room in which it sits to be shielded. It also means that any ferrous metal isn't allowed anywhere in the room. The magnetic field is strong enough to wipe out your camera's memory cards and can also damage both the imaging sensor circuits in your camera, as well as the electro-magnets that drive the shutters and aperture blades in modern cameras.

We could not put lights in the room and we had to shoot from just outside the door which isn't the best recipe for composing a great image!

Our strategy was to figure out the dominant light temperature within the room and then supplement, through the doorway and via the heavily screened observation window about eight feet to the right of the camera position. The overwhelming majority of the existing light in the room was about 3,000K with a small dose of green. In most situations (those without MRI machines to deal with...) we'd just turn off the room lights and re-light the room with flash, or our choice of continuous light. But turning off the room lights in this situation meant that the back half of the room would go dark, which would look unnatural.

I filtered a strobe with a 3200K correction gel and put the strobe into a 24x36 inch softbox, positioning it near the top of the doorway, about three feet above the camera. Then we took one of our battery powered LEDs, covered it with the same gel material and aimed it through the observation window. The combination did a decent job lighting our two techs and their "patient" but there is more we can do in post to enhance the photo. We'll select the people and get their flesh tones into a pleasing color range and then inverse our selections and balance the light in the room a bit more. But the filters and the additional light went a long way toward cleaning up a visual catastrophe.

During the day it became (once again) very clear to me that the lighting in situations like this is nearly always more important and harder to achieve than getting the camera gear right. In retrospect I could have shot all day long with one GH5 and one 12-100mm f4.0 zoom lens but over the course of the same day we used five different flashes and three different LED panels in order to get a natural and pleasing look to the light in each scene.

Had we brought a $100,000 Phase One medium format camera and no lighting we would have been much less successful. Color balance works the same across all formats. Mixed light nearly always needs to be corrected. With no lights and a super high res camera we'd have many highly detailed unusable files to play with. Conversely, I could have brought along that old Nikon D2XS and some ancient, manual focus Nikon lenses and, together with a box of strobes, could have done photographic work that would fit into the use envelope of my client, regardless of the media selected for final output.

Everyone seems to couch their shooting needs in terms of camera capabilities but in the commercial field it's generally lighting that rules the day. You can spend a fortune on a great camera and I'll concede that with the same lighting you'll make images that are fractionally better than images made with a lesser spec'd camera. The differences might not make any visual difference at all in most uses; for instance if the images are to be used on websites or inserted into video programming, etc. But for most of the work I do, which is profitable and fun, there is no need for fast frame rates, no need for super high ISO performance, and no need for spectacular resolution. There is always a need for good lighting even if it's just to clean up the lighting inconsistencies of a tough room.

We used a collection of cheap speed lights to do our work on Saturday. Nothing over $150 per light. All of the flashes could be sync'd to radio triggers or slaved from each other. Having five (an investment of about $700) meant I could put them in small places and add light to areas that needed more light without running cables. We use the lights in the same modifiers we've bought for our bigger mono-lights. Softboxes, umbrellas, diffusion disks; you name it.

One thing we lean on a lot is the intertwined use of LEDs with the small flashes. Most mono-light have tungsten modeling lights and when we need to drag the shutter in a combination flash and ambient light exposures used to make the screens on computers or the panel lights on machines glow correctly we get tungsten contamination in our daylight leaning shots. But it's nice to have a modeling light as a work light for focusing. It's common practice for us now to just grab a daylight balanced LED and bounce it off a ceiling, or even off the front end of the modifier we're using for flash. We get the focusing benefits of a modeling light and no color contamination of our mostly daylight flash exposure. Nice when it all works together...

During most of the day I worked the camera around ISO 200 and ISO 400. Using a smaller format meant I could use wider apertures and still get the depth of field I needed to get both techs, patients and machines in acceptable focus. All of our lighting units and modifiers fit into one, big rolling case and, since the battery powered strobes are small and light, we were able to use smaller, lighter light stands which helped us keep our overall footprint smaller and the overall weight load lighter.

Generally, on locations, the use of the camera is never a puzzle or mystery. Use the lens that gets you the composition you want and you are good. Lighting is a totally different story. Some rooms are filled with reflective surfaces that have to be tamed. Lights have to be placed just right for best effect, and all of it has to be balanced so nothing sticks out and beats our viewing audience over the head.

Think you need a kick ass camera? Think again; what you really might need are some kick ass lighting skills. Nine time out of ten it's the lighting that makes you the money.

At the end of the day we'd done 36 different shots (nine locations with variations in each) and amassed 1585 raw files. I can't think of a single shot on which I did not use at least two lights. Usually three or more. We edited the take down to about 600 and delivered the online gallery on Monday. This was our third day of shooting for this client in the last 30 days. We are scheduling additional shoots for this client in April. We must be doing something right.... maybe it's the lighting...


6 comments:

Anonymous said...

As a happy amateur, as in have no desire to work with photography but likes the subject, I really appreciate these behind the scenes posts. I think they really drive home the concept of the only easy jobs being other people's.
It show that as always nothing beats preparation and thinking things through and doing specific things on purpose.
It's not only in photography that people and corporations fall for the lie that all it takes is buying the newest to get ahead.

Just thought I'd write to let you know the effort on these posts is very much appreciated even though you had a few problems with idiotic comments recently. Thanks from a brazillian m43 enthusiast.

David said...

I think you hit the next AI need in cellphone photography. Imagine if google had software to selectively colour balance across an image. Then with the current photo library, an expected image gallery, your phone could provide the images you would expect.
Just thinking outside the box, but maybe what is really holding up the lazy photographers, well that and actually learning how to do it correctly rather than having a camera do all the work.

Brandon Scott said...

Kirk, I always check your blog even though my type of photography (birds, landscapes, and nature) is completely different. I learn so much about the craft, the business and how to think about a photographic situation. Keep up the great work. Oh, by the way, I pick the occasional tip for when I have to photograph family or friends. Birds don't talk back.
A number of years ago when you first started experimenting with micro 4/3s, I picked up a Panansonic G3 and then some of those great lens when they went on sale and now I have a rather full kit. I still use the Nikon and 500mm f4 for birds, but I have almost completely moved over to Pany G85 (soon to get G9) for landscape, flowers, etc. Prints as large as I need and it is some much easier to travel with.
Love the variety of your posts. It's always an informed position, even when I disagree ;-)

Dogster said...

Love this posting. I love everything your write I am finding. My main interest is lighting, always has been. I love the tip about using small LED's as modeling lamps for the flash. Previously you showed a set up you did for small flash which did not have model lamps, I thought was brilliant and I worked that into my flash system, just because I knew how. Your writing is amazing, a dedicated daily reader here. Thank You.

Peter said...

Interesting post. I'm wondering how you knew that the room is 3000K with a touch of green? Did you use a meter? Test with a grey card and camera? Eyeball it and use experience? I'm most interested! The other thing is the gels. You refer to those in your books (which are very helpful btw.). I think these are bought in sheets that can be cut to size for different equipment. Available at B&H?

Sorry for all the questions. Hope you have a moment to reply.

Thanks,
Peter Wright.

E. T. (Tom) Suter said...

As usual (I have been a lurker here for years) this was quite interesting. I am an engineer by trade and definitely just an amateur when it comes to photography, but many decades ago I learned the hard way about the relative importance of lighting. It was emotionally satisfying to see a professional agree with my beliefs.

However, what got me off my tush to respond today is actually your comments about the problems created by the presence of the MRI machine. I was under the impression that the magnetic fields around the machine were from electromagnetism, not from permanent magnets. Accordingly, I would have thought that it would have been possible to just turn off the machine, given that these were posed photos.

I work in Aerospace, not electronics, so I really have only surface knowledge of the subject. However, I believe that the MRI process depends upon gradients in the magnetic field, which I would think would be most easily created by electromagnetism. Is this another case where a little knowledge can lead to egg on the face?

With best wishes,
- Tom -