The ISO Stratosphere

This image of our grandson was made at ISO 1600 with my 85mm f/1.8, which is an excellent lens for limited light situations.
This image of our grandson was made at ISO 1600 with my 85mm f/1.8, which is an excellent lens for limited light situations.

Q: What do vegetarian zombies crave?
A: Graaains!

As a news and sports photographer, I am often tasked to shoot in less than ideal lighting situations. Sometimes those situations are less than less than ideal.

From small high schools who can’t afford new lights for the football field, to small colleges whose field houses date back 85 years, to candlelight vigils on the courthouse steps at 9 p.m., to house fires at two in the morning, those of us who shoot news photos shoot a lot of stuff in light that can sometimes challenge not just our cameras, but human vision itself.

The first thing we have to change when we go from well-lit scenes to the dim places is ISO. ISO, which merely stands for International Organization for Standardization (yes, I know that would be IOS, but here we are), in the digital photography world describes how sensitive our imaging sensor is to light. To make the sensor more sensitive require electronically amplifying to signals it produces, which also amplifies the noise in the circuitry. In recent years, techniques to do this have improved dramatically, but there is still a price to be paid for shooting at those high ISO settings. In the era before digital we described this “noise” as grain or graininess.

A big part of solving the problem of low light is to pick the right lenses.

I have told my students a number of times that almost any lens is going to yield good results on a sunny day at f/8. The real test of a lens is how it will perform on the margins of photography, or under stress.

What do I mean by that? It’s actually pretty rare, for example, that I shoot football in the daytime. In fact, the high schools never play in the day, and the college I cover only plays the last couple of games of the season in the daytime. The rest of the time I am shooting football under stadium lights, almost always at the widest apertures a lens has, at close to the highest ISOs my camera has, at shutter speeds that are barely adequate to freeze the action. All these factors put my skills, and a lens, to the ultimate test.

This is the Sigma 17-50mm f/2.8 I bought just prior to my sister's wedding. It proved to be an excellent purchase.
This is the Sigma 17-50mm f/2.8 I bought just prior to my sister's wedding. It proved to be an excellent purchase.

This isn’t a brick wall shot at f/8 to determine sharpness like you see all too often on photography forums. People on these forums shoot these brick walls or teddy bears on the desk in the den or London Bridge, usually hoping to make some point about the equipment. Does the lens have chromatic abberration? Does the sensor show banding? Is there a problem with the autofocus?

Hopefully you and I are beyond all that, and are taking pictures in the real world, and in the real world we need good lenses. But good in what way? If a lens has 2.5% pincushion distortion at f/5.6 at 1/500th of a second in broad daylight: irrelevant. If a lens can give you a decent image wide open at 1/125th handheld at ISO3200? That’s what we need.

I’m not talking to studio photographers. I’m talking to those of us who shoot where the world is rough. I’m talking about jumping out of your car 20 minutes after sunset because you just got to the top of the hill where you could see that perfect tree against the fading light, and only have a few seconds to get the shot. I’m talking about flames shooting out of a warehouse window three blocks away because you’re stuck behind crime scene tape. That’s my world all the time.

I shot my sister’s wedding in December 2011 with a new Sigma 17-50mm f/2.8. I have a similar lens at work, but did not own one myself, so I thought it would be a smart buy. I ended up loving it, and the wedding images, plus everything I have shot with it since then, are great. The event was in a large room lit by four incandescent chandeliers, which gave a smooth, even light, albeit not a lot of it. I shot at ISO 3200 at f/2.8 in aperture priority mode, and shutter speeds fell into the 1/60 to 1/125 range. That’s not exactly a blisteringly fast shutter speed, but other factors can help make up for it, like lens sharpness.

I certainly could have shot the whole thing with flash, but quite honestly, I have never loved the look of bounce flash, and I despise the results of direct flash.

Of course I shot RAW files, which allowed me to milk the most out of the scenes, and reduce the noise I got from the high ISO setting. In the end, one of the reasons my images of the wedding were so successful was that I had a great lens in front of the camera.

Tracey and Nicole cut their wedding "cake" (actually doughnuts). You can see that although there wasn't much of it, the light had a magical quality to it.
Tracey and Nicole cut their wedding "cake" (actually doughnuts). You can see that although there wasn't much of it, the light had a magical quality to it.
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1 Comment

  1. Great read.

    I’ve just been testing my new camera at ISO6400 and 12800, something that was impossible with my older cameras. It’s interesting how much this opens up low light shooting…

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